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• Matplotlib plotting non uniform data in 3D surface

  - by Raj Tendulkar

  I have a simple code to plot the points in 3D for Matplotlib as below - from mpl_toolkits.mplot3d import axes3d import matplotlib.pyplot as plt import numpy as np from numpy import genfromtxt import csv fig = plt.figure() ax = fig.add_subplot(111, projection='3d') my_data = genfromtxt('points1.csv', delimiter=',') points1X = my_data[:,0] points1Y = my_data[:,1] points1Z = my_data[:,2] ## I remove the header of the CSV File. points1X = np.delete(points1X, 0) points1Y = np.delete(points1Y, 0) points1Z = np.delete(points1Z, 0) # Convert the array to 1D array points1X = np.reshape(points1X,points1X.size) points1Y = np.reshape(points1Y,points1Y.size) points1Z = np.reshape(points1Z,points1Z.size) my_data = genfromtxt('points2.csv', delimiter=',') points2X = my_data[:,0] points2Y = my_data[:,1] points2Z = my_data[:,2] ## I remove the header of the CSV File. points2X = np.delete(points2X, 0) points2Y = np.delete(points2Y, 0) points2Z = np.delete(points2Z, 0) # Convert the array to 1D array points2X = np.reshape(points2X,points2X.size) points2Y = np.reshape(points2Y,points2Y.size) points2Z = np.reshape(points2Z,points2Z.size) ax.plot(points1X, points1Y, points1Z, 'd', markersize=8, markerfacecolor='red', label='points1') ax.plot(points2X, points2Y, points2Z, 'd', markersize=8, markerfacecolor='blue', label='points2') plt.show() My problem is that I tried to make a decent surface plot out of these data points that I have. I already tried to use ax.plot_surface() function to make it look nice. For this I eliminated some points, and recalculated the matrix kind of input needed by this function. However, the graph I generated was far more difficult to interpret and understand. So there might be 2 possibilities: either I am not using the function correctly, or otherwise, the data I am trying to plot is not good for the surface plot. What I was expecting was 3D graph which would have an effect similar to that we have of 3D pie chart. We see that one piece (that which is extracted out) is part of another piece. I was not expecting it to be exactly same like that, but some kind of effect like that. What I would like to ask is: Do you think it will be possible to make such 3D graph? Is there any way better, I could express my data in 3 dimension? Here are the 2 files - points1.csv Dim1,Dim2,Dim3 3,8,1 3,8,2 3,8,3 3,8,4 3,8,5 3,9,1 3,9,2 3,9,3 3,9,4 3,9,5 3,10,1 3,10,2 3,10,3 3,10,4 3,10,5 3,11,1 3,11,2 3,11,3 3,11,4 3,11,5 3,12,1 3,12,2 3,13,1 3,13,2 3,14,1 3,14,2 3,15,1 3,15,2 3,16,1 3,16,2 3,17,1 3,17,2 3,18,1 3,18,2 4,8,1 4,8,2 4,8,3 4,8,4 4,8,5 4,9,1 4,9,2 4,9,3 4,9,4 4,9,5 4,10,1 4,10,2 4,10,3 4,10,4 4,10,5 4,11,1 4,11,2 4,11,3 4,11,4 4,11,5 4,12,1 4,13,1 4,14,1 4,15,1 4,16,1 4,17,1 4,18,1 5,8,1 5,8,2 5,8,3 5,8,4 5,8,5 5,9,1 5,9,2 5,9,3 5,9,4 5,9,5 5,10,1 5,10,2 5,10,3 5,10,4 5,10,5 5,11,1 5,11,2 5,11,3 5,11,4 5,11,5 5,12,1 5,13,1 5,14,1 5,15,1 5,16,1 5,17,1 5,18,1 6,8,1 6,8,2 6,8,3 6,8,4 6,8,5 6,9,1 6,9,2 6,9,3 6,9,4 6,9,5 6,10,1 6,11,1 6,12,1 6,13,1 6,14,1 6,15,1 6,16,1 6,17,1 6,18,1 7,8,1 7,8,2 7,8,3 7,8,4 7,8,5 7,9,1 7,9,2 7,9,3 7,9,4 7,9,5 and points2.csv Dim1,Dim2,Dim3 3,12,3 3,12,4 3,12,5 3,13,3 3,13,4 3,13,5 3,14,3 3,14,4 3,14,5 3,15,3 3,15,4 3,15,5 3,16,3 3,16,4 3,16,5 3,17,3 3,17,4 3,17,5 3,18,3 3,18,4 3,18,5 4,12,2 4,12,3 4,12,4 4,12,5 4,13,2 4,13,3 4,13,4 4,13,5 4,14,2 4,14,3 4,14,4 4,14,5 4,15,2 4,15,3 4,15,4 4,15,5 4,16,2 4,16,3 4,16,4 4,16,5 4,17,2 4,17,3 4,17,4 4,17,5 4,18,2 4,18,3 4,18,4 4,18,5 5,12,2 5,12,3 5,12,4 5,12,5 5,13,2 5,13,3 5,13,4 5,13,5 5,14,2 5,14,3 5,14,4 5,14,5 5,15,2 5,15,3 5,15,4 5,15,5 5,16,2 5,16,3 5,16,4 5,16,5 5,17,2 5,17,3 5,17,4 5,17,5 5,18,2 5,18,3 5,18,4 5,18,5 6,10,2 6,10,3 6,10,4 6,10,5 6,11,2 6,11,3 6,11,4 6,11,5 6,12,2 6,12,3 6,12,4 6,12,5 6,13,2 6,13,3 6,13,4 6,13,5 6,14,2 6,14,3 6,14,4 6,14,5 6,15,2 6,15,3 6,15,4 6,15,5 6,16,2 6,16,3 6,16,4 6,16,5 6,17,2 6,17,3 6,17,4 6,17,5 6,18,2 6,18,3 6,18,4 6,18,5 7,10,1 7,10,2 7,10,3 7,10,4 7,10,5 7,11,1 7,11,2 7,11,3 7,11,4 7,11,5 7,12,1 7,12,2 7,12,3 7,12,4 7,12,5 7,13,1 7,13,2 7,13,3 7,13,4 7,13,5 7,14,1 7,14,2 7,14,3 7,14,4 7,14,5 7,15,1 7,15,2 7,15,3 7,15,4 7,15,5 7,16,1 7,16,2 7,16,3 7,16,4 7,16,5 7,17,1 7,17,2 7,17,3 7,17,4 7,17,5 7,18,1 7,18,2 7,18,3 7,18,4 7,18,5

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• How to find and fix performance problems in ORM powered applications

  - by FransBouma

  Once in a while we get requests about how to fix performance problems with our framework. As it comes down to following the same steps and looking into the same things every single time, I decided to write a blogpost about it instead, so more people can learn from this and solve performance problems in their O/R mapper powered applications. In some parts it's focused on LLBLGen Pro but it's also usable for other O/R mapping frameworks, as the vast majority of performance problems in O/R mapper powered applications are not specific for a certain O/R mapper framework. Too often, the developer looks at the wrong part of the application, trying to fix what isn't a problem in that part, and getting frustrated that 'things are so slow with <insert your favorite framework X here>'. I'm in the O/R mapper business for a long time now (almost 10 years, full time) and as it's a small world, we O/R mapper developers know almost all tricks to pull off by now: we all know what to do to make task ABC faster and what compromises (because there are almost always compromises) to deal with if we decide to make ABC faster that way. Some O/R mapper frameworks are faster in X, others in Y, but you can be sure the difference is mainly a result of a compromise some developers are willing to deal with and others aren't. That's why the O/R mapper frameworks on the market today are different in many ways, even though they all fetch and save entities from and to a database. I'm not suggesting there's no room for improvement in today's O/R mapper frameworks, there always is, but it's not a matter of 'the slowness of the application is caused by the O/R mapper' anymore. Perhaps query generation can be optimized a bit here, row materialization can be optimized a bit there, but it's mainly coming down to milliseconds. Still worth it if you're a framework developer, but it's not much compared to the time spend inside databases and in user code: if a complete fetch takes 40ms or 50ms (from call to entity object collection), it won't make a difference for your application as that 10ms difference won't be noticed. That's why it's very important to find the real locations of the problems so developers can fix them properly and don't get frustrated because their quest to get a fast, performing application failed. Performance tuning basics and rules Finding and fixing performance problems in any application is a strict procedure with four prescribed steps: isolate, analyze, interpret and fix, in that order. It's key that you don't skip a step nor make assumptions: these steps help you find the reason of a problem which seems to be there, and how to fix it or leave it as-is. Skipping a step, or when you assume things will be bad/slow without doing analysis will lead to the path of premature optimization and won't actually solve your problems, only create new ones. The most important rule of finding and fixing performance problems in software is that you have to understand what 'performance problem' actually means. Most developers will say "when a piece of software / code is slow, you have a performance problem". But is that actually the case? If I write a Linq query which will aggregate, group and sort 5 million rows from several tables to produce a resultset of 10 rows, it might take more than a couple of milliseconds before that resultset is ready to be consumed by other logic. If I solely look at the Linq query, the code consuming the resultset of the 10 rows and then look at the time it takes to complete the whole procedure, it will appear to me to be slow: all that time taken to produce and consume 10 rows? But if you look closer, if you analyze and interpret the situation, you'll see it does a tremendous amount of work, and in that light it might even be extremely fast. With every performance problem you encounter, always do realize that what you're trying to solve is perhaps not a technical problem at all, but a perception problem. The second most important rule you have to understand is based on the old saying "Penny wise, Pound Foolish": the part which takes e.g. 5% of the total time T for a given task isn't worth optimizing if you have another part which takes a much larger part of the total time T for that same given task. Optimizing parts which are relatively insignificant for the total time taken is not going to bring you better results overall, even if you totally optimize that part away. This is the core reason why analysis of the complete set of application parts which participate in a given task is key to being successful in solving performance problems: No analysis -> no problem -> no solution. One warning up front: hunting for performance will always include making compromises. Fast software can be made maintainable, but if you want to squeeze as much performance out of your software, you will inevitably be faced with the dilemma of compromising one or more from the group {readability, maintainability, features} for the extra performance you think you'll gain. It's then up to you to decide whether it's worth it. In almost all cases it's not. The reason for this is simple: the vast majority of performance problems can be solved by implementing the proper algorithms, the ones with proven Big O-characteristics so you know the performance you'll get plus you know the algorithm will work. The time taken by the algorithm implementing code is inevitable: you already implemented the best algorithm. You might find some optimizations on the technical level but in general these are minor. Let's look at the four steps to see how they guide us through the quest to find and fix performance problems. Isolate The first thing you need to do is to isolate the areas in your application which are assumed to be slow. For example, if your application is a web application and a given page is taking several seconds or even minutes to load, it's a good candidate to check out. It's important to start with the isolate step because it allows you to focus on a single code path per area with a clear begin and end and ignore the rest. The rest of the steps are taken per identified problematic area. Keep in mind that isolation focuses on tasks in an application, not code snippets. A task is something that's started in your application by either another task or the user, or another program, and has a beginning and an end. You can see a task as a piece of functionality offered by your application.  Analyze Once you've determined the problem areas, you have to perform analysis on the code paths of each area, to see where the performance problems occur and which areas are not the problem. This is a multi-layered effort: an application which uses an O/R mapper typically consists of multiple parts: there's likely some kind of interface (web, webservice, windows etc.), a part which controls the interface and business logic, the O/R mapper part and the RDBMS, all connected with either a network or inter-process connections provided by the OS or other means. Each of these parts, including the connectivity plumbing, eat up a part of the total time it takes to complete a task, e.g. load a webpage with all orders of a given customer X. To understand which parts participate in the task / area we're investigating and how much they contribute to the total time taken to complete the task, analysis of each participating task is essential. Start with the code you wrote which starts the task, analyze the code and track the path it follows through your application. What does the code do along the way, verify whether it's correct or not. Analyze whether you have implemented the right algorithms in your code for this particular area. Remember we're looking at one area at a time, which means we're ignoring all other code paths, just the code path of the current problematic area, from begin to end and back. Don't dig in and start optimizing at the code level just yet. We're just analyzing. If your analysis reveals big architectural stupidity, it's perhaps a good idea to rethink the architecture at this point. For the rest, we're analyzing which means we collect data about what could be wrong, for each participating part of the complete application. Reviewing the code you wrote is a good tool to get deeper understanding of what is going on for a given task but ultimately it lacks precision and overview what really happens: humans aren't good code interpreters, computers are. We therefore need to utilize tools to get deeper understanding about which parts contribute how much time to the total task, triggered by which other parts and for example how many times are they called. There are two different kind of tools which are necessary: .NET profilers and O/R mapper / RDBMS profilers. .NET profiling .NET profilers (e.g. dotTrace by JetBrains or Ants by Red Gate software) show exactly which pieces of code are called, how many times they're called, and the time it took to run that piece of code, at the method level and sometimes even at the line level. The .NET profilers are essential tools for understanding whether the time taken to complete a given task / area in your application is consumed by .NET code, where exactly in your code, the path to that code, how many times that code was called by other code and thus reveals where hotspots are located: the areas where a solution can be found. Importantly, they also reveal which areas can be left alone: remember our penny wise pound foolish saying: if a profiler reveals that a group of methods are fast, or don't contribute much to the total time taken for a given task, ignore them. Even if the code in them is perhaps complex and looks like a candidate for optimization: you can work all day on that, it won't matter.  As we're focusing on a single area of the application, it's best to start profiling right before you actually activate the task/area. Most .NET profilers support this by starting the application without starting the profiling procedure just yet. You navigate to the particular part which is slow, start profiling in the profiler, in your application you perform the actions which are considered slow, and afterwards you get a snapshot in the profiler. The snapshot contains the data collected by the profiler during the slow action, so most data is produced by code in the area to investigate. This is important, because it allows you to stay focused on a single area. O/R mapper and RDBMS profiling .NET profilers give you a good insight in the .NET side of things, but not in the RDBMS side of the application. As this article is about O/R mapper powered applications, we're also looking at databases, and the software making it possible to consume the database in your application: the O/R mapper. To understand which parts of the O/R mapper and database participate how much to the total time taken for task T, we need different tools. There are two kind of tools focusing on O/R mappers and database performance profiling: O/R mapper profilers and RDBMS profilers. For O/R mapper profilers, you can look at LLBLGen Prof by hibernating rhinos or the Linq to Sql/LLBLGen Pro profiler by Huagati. Hibernating rhinos also have profilers for other O/R mappers like NHibernate (NHProf) and Entity Framework (EFProf) and work the same as LLBLGen Prof. For RDBMS profilers, you have to look whether the RDBMS vendor has a profiler. For example for SQL Server, the profiler is shipped with SQL Server, for Oracle it's build into the RDBMS, however there are also 3rd party tools. Which tool you're using isn't really important, what's important is that you get insight in which queries are executed during the task / area we're currently focused on and how long they took. Here, the O/R mapper profilers have an advantage as they collect the time it took to execute the query from the application's perspective so they also collect the time it took to transport data across the network. This is important because a query which returns a massive resultset or a resultset with large blob/clob/ntext/image fields takes more time to get transported across the network than a small resultset and a database profiler doesn't take this into account most of the time. Another tool to use in this case, which is more low level and not all O/R mappers support it (though LLBLGen Pro and NHibernate as well do) is tracing: most O/R mappers offer some form of tracing or logging system which you can use to collect the SQL generated and executed and often also other activity behind the scenes. While tracing can produce a tremendous amount of data in some cases, it also gives insight in what's going on. Interpret After we've completed the analysis step it's time to look at the data we've collected. We've done code reviews to see whether we've done anything stupid and which parts actually take place and if the proper algorithms have been implemented. We've done .NET profiling to see which parts are choke points and how much time they contribute to the total time taken to complete the task we're investigating. We've performed O/R mapper profiling and RDBMS profiling to see which queries were executed during the task, how many queries were generated and executed and how long they took to complete, including network transportation. All this data reveals two things: which parts are big contributors to the total time taken and which parts are irrelevant. Both aspects are very important. The parts which are irrelevant (i.e. don't contribute significantly to the total time taken) can be ignored from now on, we won't look at them. The parts which contribute a lot to the total time taken are important to look at. We now have to first look at the .NET profiler results, to see whether the time taken is consumed in our own code, in .NET framework code, in the O/R mapper itself or somewhere else. For example if most of the time is consumed by DbCommand.ExecuteReader, the time it took to complete the task is depending on the time the data is fetched from the database. If there was just 1 query executed, according to tracing or O/R mapper profilers / RDBMS profilers, check whether that query is optimal, uses indexes or has to deal with a lot of data. Interpret means that you follow the path from begin to end through the data collected and determine where, along the path, the most time is contributed. It also means that you have to check whether this was expected or is totally unexpected. My previous example of the 10 row resultset of a query which groups millions of rows will likely reveal that a long time is spend inside the database and almost no time is spend in the .NET code, meaning the RDBMS part contributes the most to the total time taken, the rest is compared to that time, irrelevant. Considering the vastness of the source data set, it's expected this will take some time. However, does it need tweaking? Perhaps all possible tweaks are already in place. In the interpret step you then have to decide that further action in this area is necessary or not, based on what the analysis results show: if the analysis results were unexpected and in the area where the most time is contributed to the total time taken is room for improvement, action should be taken. If not, you can only accept the situation and move on. In all cases, document your decision together with the analysis you've done. If you decide that the perceived performance problem is actually expected due to the nature of the task performed, it's essential that in the future when someone else looks at the application and starts asking questions you can answer them properly and new analysis is only necessary if situations changed. Fix After interpreting the analysis results you've concluded that some areas need adjustment. This is the fix step: you're actively correcting the performance problem with proper action targeted at the real cause. In many cases related to O/R mapper powered applications it means you'll use different features of the O/R mapper to achieve the same goal, or apply optimizations at the RDBMS level. It could also mean you apply caching inside your application (compromise memory consumption over performance) to avoid unnecessary re-querying data and re-consuming the results. After applying a change, it's key you re-do the analysis and interpretation steps: compare the results and expectations with what you had before, to see whether your actions had any effect or whether it moved the problem to a different part of the application. Don't fall into the trap to do partly analysis: do the full analysis again: .NET profiling and O/R mapper / RDBMS profiling. It might very well be that the changes you've made make one part faster but another part significantly slower, in such a way that the overall problem hasn't changed at all. Performance tuning is dealing with compromises and making choices: to use one feature over the other, to accept a higher memory footprint, to go away from the strict-OO path and execute queries directly onto the RDBMS, these are choices and compromises which will cross your path if you want to fix performance problems with respect to O/R mappers or data-access and databases in general. In most cases it's not a big issue: alternatives are often good choices too and the compromises aren't that hard to deal with. What is important is that you document why you made a choice, a compromise: which analysis data, which interpretation led you to the choice made. This is key for good maintainability in the years to come. Most common performance problems with O/R mappers Below is an incomplete list of common performance problems related to data-access / O/R mappers / RDBMS code. It will help you with fixing the hotspots you found in the interpretation step. SELECT N+1: (Lazy-loading specific). Lazy loading triggered performance bottlenecks. Consider a list of Orders bound to a grid. You have a Field mapped onto a related field in Order, Customer.CompanyName. Showing this column in the grid will make the grid fetch (indirectly) for each row the Customer row. This means you'll get for the single list not 1 query (for the orders) but 1+(the number of orders shown) queries. To solve this: use eager loading using a prefetch path to fetch the customers with the orders. SELECT N+1 is easy to spot with an O/R mapper profiler or RDBMS profiler: if you see a lot of identical queries executed at once, you have this problem. Prefetch paths using many path nodes or sorting, or limiting. Eager loading problem. Prefetch paths can help with performance, but as 1 query is fetched per node, it can be the number of data fetched in a child node is bigger than you think. Also consider that data in every node is merged on the client within the parent. This is fast, but it also can take some time if you fetch massive amounts of entities. If you keep fetches small, you can use tuning parameters like the ParameterizedPrefetchPathThreshold setting to get more optimal queries. Deep inheritance hierarchies of type Target Per Entity/Type. If you use inheritance of type Target per Entity / Type (each type in the inheritance hierarchy is mapped onto its own table/view), fetches will join subtype- and supertype tables in many cases, which can lead to a lot of performance problems if the hierarchy has many types. With this problem, keep inheritance to a minimum if possible, or switch to a hierarchy of type Target Per Hierarchy, which means all entities in the inheritance hierarchy are mapped onto the same table/view. Of course this has its own set of drawbacks, but it's a compromise you might want to take. Fetching massive amounts of data by fetching large lists of entities. LLBLGen Pro supports paging (and limiting the # of rows returned), which is often key to process through large sets of data. Use paging on the RDBMS if possible (so a query is executed which returns only the rows in the page requested). When using paging in a web application, be sure that you switch server-side paging on on the datasourcecontrol used. In this case, paging on the grid alone is not enough: this can lead to fetching a lot of data which is then loaded into the grid and paged there. Keep note that analyzing queries for paging could lead to the false assumption that paging doesn't occur, e.g. when the query contains a field of type ntext/image/clob/blob and DISTINCT can't be applied while it should have (e.g. due to a join): the datareader will do DISTINCT filtering on the client. this is a little slower but it does perform paging functionality on the data-reader so it won't fetch all rows even if the query suggests it does. Fetch massive amounts of data because blob/clob/ntext/image fields aren't excluded. LLBLGen Pro supports field exclusion for queries. You can exclude fields (also in prefetch paths) per query to avoid fetching all fields of an entity, e.g. when you don't need them for the logic consuming the resultset. Excluding fields can greatly reduce the amount of time spend on data-transport across the network. Use this optimization if you see that there's a big difference between query execution time on the RDBMS and the time reported by the .NET profiler for the ExecuteReader method call. Doing client-side aggregates/scalar calculations by consuming a lot of data. If possible, try to formulate a scalar query or group by query using the projection system or GetScalar functionality of LLBLGen Pro to do data consumption on the RDBMS server. It's far more efficient to process data on the RDBMS server than to first load it all in memory, then traverse the data in-memory to calculate a value. Using .ToList() constructs inside linq queries. It might be you use .ToList() somewhere in a Linq query which makes the query be run partially in-memory. Example: var q = from c in metaData.Customers.ToList() where c.Country=="Norway" select c; This will actually fetch all customers in-memory and do an in-memory filtering, as the linq query is defined on an IEnumerable<T>, and not on the IQueryable<T>. Linq is nice, but it can often be a bit unclear where some parts of a Linq query might run. Fetching all entities to delete into memory first. To delete a set of entities it's rather inefficient to first fetch them all into memory and then delete them one by one. It's more efficient to execute a DELETE FROM ... WHERE query on the database directly to delete the entities in one go. LLBLGen Pro supports this feature, and so do some other O/R mappers. It's not always possible to do this operation in the context of an O/R mapper however: if an O/R mapper relies on a cache, these kind of operations are likely not supported because they make it impossible to track whether an entity is actually removed from the DB and thus can be removed from the cache. Fetching all entities to update with an expression into memory first. Similar to the previous point: it is more efficient to update a set of entities directly with a single UPDATE query using an expression instead of fetching the entities into memory first and then updating the entities in a loop, and afterwards saving them. It might however be a compromise you don't want to take as it is working around the idea of having an object graph in memory which is manipulated and instead makes the code fully aware there's a RDBMS somewhere. Conclusion Performance tuning is almost always about compromises and making choices. It's also about knowing where to look and how the systems in play behave and should behave. The four steps I provided should help you stay focused on the real problem and lead you towards the solution. Knowing how to optimally use the systems participating in your own code (.NET framework, O/R mapper, RDBMS, network/services) is key for success as well as knowing what's going on inside the application you built. I hope you'll find this guide useful in tracking down performance problems and dealing with them in a useful way.  

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• How LINQ to Object statements work

  - by rajbk

  This post goes into detail as to now LINQ statements work when querying a collection of objects. This topic assumes you have an understanding of how generics, delegates, implicitly typed variables, lambda expressions, object/collection initializers, extension methods and the yield statement work. I would also recommend you read my previous two posts: Using Delegates in C# Part 1 Using Delegates in C# Part 2 We will start by writing some methods to filter a collection of data. Assume we have an Employee class like so: 1: public class Employee { 2: public int ID { get; set;} 3: public string FirstName { get; set;} 4: public string LastName {get; set;} 5: public string Country { get; set; } 6: } and a collection of employees like so: 1: var employees = new List<Employee> { 2: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 3: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 4: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 5: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" }, 6: }; Filtering We wish to  find all employees that have an even ID. We could start off by writing a method that takes in a list of employees and returns a filtered list of employees with an even ID. 1: static List<Employee> GetEmployeesWithEvenID(List<Employee> employees) { 2: var filteredEmployees = new List<Employee>(); 3: foreach (Employee emp in employees) { 4: if (emp.ID % 2 == 0) { 5: filteredEmployees.Add(emp); 6: } 7: } 8: return filteredEmployees; 9: } The method can be rewritten to return an IEnumerable<Employee> using the yield return keyword. 1: static IEnumerable<Employee> GetEmployeesWithEvenID(IEnumerable<Employee> employees) { 2: foreach (Employee emp in employees) { 3: if (emp.ID % 2 == 0) { 4: yield return emp; 5: } 6: } 7: } We put these together in a console application. 1: using System; 2: using System.Collections.Generic; 3: //No System.Linq 4:  5: public class Program 6: { 7: [STAThread] 8: static void Main(string[] args) 9: { 10: var employees = new List<Employee> { 11: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 12: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 13: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 14: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" }, 15: }; 16: var filteredEmployees = GetEmployeesWithEvenID(employees); 17:  18: foreach (Employee emp in filteredEmployees) { 19: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 20: emp.ID, emp.FirstName, emp.LastName, emp.Country); 21: } 22:  23: Console.ReadLine(); 24: } 25: 26: static IEnumerable<Employee> GetEmployeesWithEvenID(IEnumerable<Employee> employees) { 27: foreach (Employee emp in employees) { 28: if (emp.ID % 2 == 0) { 29: yield return emp; 30: } 31: } 32: } 33: } 34:  35: public class Employee { 36: public int ID { get; set;} 37: public string FirstName { get; set;} 38: public string LastName {get; set;} 39: public string Country { get; set; } 40: } Output: ID 2 First_Name Jim Last_Name Ashlock Country UK ID 4 First_Name Jill Last_Name Anderson Country AUS Our filtering method is too specific. Let us change it so that it is capable of doing different types of filtering and lets give our method the name Where ;-) We will add another parameter to our Where method. This additional parameter will be a delegate with the following declaration. public delegate bool Filter(Employee emp); The idea is that the delegate parameter in our Where method will point to a method that contains the logic to do our filtering thereby freeing our Where method from any dependency. The method is shown below: 1: static IEnumerable<Employee> Where(IEnumerable<Employee> employees, Filter filter) { 2: foreach (Employee emp in employees) { 3: if (filter(emp)) { 4: yield return emp; 5: } 6: } 7: } Making the change to our app, we create a new instance of the Filter delegate on line 14 with a target set to the method EmployeeHasEvenId. Running the code will produce the same output. 1: public delegate bool Filter(Employee emp); 2:  3: public class Program 4: { 5: [STAThread] 6: static void Main(string[] args) 7: { 8: var employees = new List<Employee> { 9: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 10: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 11: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 12: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 13: }; 14: var filterDelegate = new Filter(EmployeeHasEvenId); 15: var filteredEmployees = Where(employees, filterDelegate); 16:  17: foreach (Employee emp in filteredEmployees) { 18: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 19: emp.ID, emp.FirstName, emp.LastName, emp.Country); 20: } 21: Console.ReadLine(); 22: } 23: 24: static bool EmployeeHasEvenId(Employee emp) { 25: return emp.ID % 2 == 0; 26: } 27: 28: static IEnumerable<Employee> Where(IEnumerable<Employee> employees, Filter filter) { 29: foreach (Employee emp in employees) { 30: if (filter(emp)) { 31: yield return emp; 32: } 33: } 34: } 35: } 36:  37: public class Employee { 38: public int ID { get; set;} 39: public string FirstName { get; set;} 40: public string LastName {get; set;} 41: public string Country { get; set; } 42: } Lets use lambda expressions to inline the contents of the EmployeeHasEvenId method in place of the method. The next code snippet shows this change (see line 15).  For brevity, the Employee class declaration has been skipped. 1: public delegate bool Filter(Employee emp); 2:  3: public class Program 4: { 5: [STAThread] 6: static void Main(string[] args) 7: { 8: var employees = new List<Employee> { 9: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 10: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 11: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 12: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 13: }; 14: var filterDelegate = new Filter(EmployeeHasEvenId); 15: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 16:  17: foreach (Employee emp in filteredEmployees) { 18: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 19: emp.ID, emp.FirstName, emp.LastName, emp.Country); 20: } 21: Console.ReadLine(); 22: } 23: 24: static bool EmployeeHasEvenId(Employee emp) { 25: return emp.ID % 2 == 0; 26: } 27: 28: static IEnumerable<Employee> Where(IEnumerable<Employee> employees, Filter filter) { 29: foreach (Employee emp in employees) { 30: if (filter(emp)) { 31: yield return emp; 32: } 33: } 34: } 35: } 36:  The output displays the same two employees.  Our Where method is too restricted since it works with a collection of Employees only. Lets change it so that it works with any IEnumerable<T>. In addition, you may recall from my previous post,  that .NET 3.5 comes with a lot of predefined delegates including public delegate TResult Func<T, TResult>(T arg); We will get rid of our Filter delegate and use the one above instead. We apply these two changes to our code. 1: public class Program 2: { 3: [STAThread] 4: static void Main(string[] args) 5: { 6: var employees = new List<Employee> { 7: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 8: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 9: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 10: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 11: }; 12:  13: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 14:  15: foreach (Employee emp in filteredEmployees) { 16: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 17: emp.ID, emp.FirstName, emp.LastName, emp.Country); 18: } 19: Console.ReadLine(); 20: } 21: 22: static IEnumerable<T> Where<T>(IEnumerable<T> source, Func<T, bool> filter) { 23: foreach (var x in source) { 24: if (filter(x)) { 25: yield return x; 26: } 27: } 28: } 29: } We have successfully implemented a way to filter any IEnumerable<T> based on a  filter criteria. Projection Now lets enumerate on the items in the IEnumerable<Employee> we got from the Where method and copy them into a new IEnumerable<EmployeeFormatted>. The EmployeeFormatted class will only have a FullName and ID property. 1: public class EmployeeFormatted { 2: public int ID { get; set; } 3: public string FullName {get; set;} 4: } We could “project” our existing IEnumerable<Employee> into a new collection of IEnumerable<EmployeeFormatted> with the help of a new method. We will call this method Select ;-) 1: static IEnumerable<EmployeeFormatted> Select(IEnumerable<Employee> employees) { 2: foreach (var emp in employees) { 3: yield return new EmployeeFormatted { 4: ID = emp.ID, 5: FullName = emp.LastName + ", " + emp.FirstName 6: }; 7: } 8: } The changes are applied to our app. 1: public class Program 2: { 3: [STAThread] 4: static void Main(string[] args) 5: { 6: var employees = new List<Employee> { 7: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 8: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 9: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 10: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 11: }; 12:  13: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 14: var formattedEmployees = Select(filteredEmployees); 15:  16: foreach (EmployeeFormatted emp in formattedEmployees) { 17: Console.WriteLine("ID {0} Full_Name {1}", 18: emp.ID, emp.FullName); 19: } 20: Console.ReadLine(); 21: } 22:  23: static IEnumerable<T> Where<T>(IEnumerable<T> source, Func<T, bool> filter) { 24: foreach (var x in source) { 25: if (filter(x)) { 26: yield return x; 27: } 28: } 29: } 30: 31: static IEnumerable<EmployeeFormatted> Select(IEnumerable<Employee> employees) { 32: foreach (var emp in employees) { 33: yield return new EmployeeFormatted { 34: ID = emp.ID, 35: FullName = emp.LastName + ", " + emp.FirstName 36: }; 37: } 38: } 39: } 40:  41: public class Employee { 42: public int ID { get; set;} 43: public string FirstName { get; set;} 44: public string LastName {get; set;} 45: public string Country { get; set; } 46: } 47:  48: public class EmployeeFormatted { 49: public int ID { get; set; } 50: public string FullName {get; set;} 51: } Output: ID 2 Full_Name Ashlock, Jim ID 4 Full_Name Anderson, Jill We have successfully selected employees who have an even ID and then shaped our data with the help of the Select method so that the final result is an IEnumerable<EmployeeFormatted>.  Lets make our Select method more generic so that the user is given the freedom to shape what the output would look like. We can do this, like before, with lambda expressions. Our Select method is changed to accept a delegate as shown below. TSource will be the type of data that comes in and TResult will be the type the user chooses (shape of data) as returned from the selector delegate. 1:  2: static IEnumerable<TResult> Select<TSource, TResult>(IEnumerable<TSource> source, Func<TSource, TResult> selector) { 3: foreach (var x in source) { 4: yield return selector(x); 5: } 6: } We see the new changes to our app. On line 15, we use lambda expression to specify the shape of the data. In this case the shape will be of type EmployeeFormatted. 1:  2: public class Program 3: { 4: [STAThread] 5: static void Main(string[] args) 6: { 7: var employees = new List<Employee> { 8: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 9: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 10: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 11: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 12: }; 13:  14: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 15: var formattedEmployees = Select(filteredEmployees, (emp) => 16: new EmployeeFormatted { 17: ID = emp.ID, 18: FullName = emp.LastName + ", " + emp.FirstName 19: }); 20:  21: foreach (EmployeeFormatted emp in formattedEmployees) { 22: Console.WriteLine("ID {0} Full_Name {1}", 23: emp.ID, emp.FullName); 24: } 25: Console.ReadLine(); 26: } 27: 28: static IEnumerable<T> Where<T>(IEnumerable<T> source, Func<T, bool> filter) { 29: foreach (var x in source) { 30: if (filter(x)) { 31: yield return x; 32: } 33: } 34: } 35: 36: static IEnumerable<TResult> Select<TSource, TResult>(IEnumerable<TSource> source, Func<TSource, TResult> selector) { 37: foreach (var x in source) { 38: yield return selector(x); 39: } 40: } 41: } The code outputs the same result as before. On line 14 we filter our data and on line 15 we project our data. What if we wanted to be more expressive and concise? We could combine both line 14 and 15 into one line as shown below. Assuming you had to perform several operations like this on our collection, you would end up with some very unreadable code! 1: var formattedEmployees = Select(Where(employees, emp => emp.ID % 2 == 0), (emp) => 2: new EmployeeFormatted { 3: ID = emp.ID, 4: FullName = emp.LastName + ", " + emp.FirstName 5: }); A cleaner way to write this would be to give the appearance that the Select and Where methods were part of the IEnumerable<T>. This is exactly what extension methods give us. Extension methods have to be defined in a static class. Let us make the Select and Where extension methods on IEnumerable<T> 1: public static class MyExtensionMethods { 2: static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> filter) { 3: foreach (var x in source) { 4: if (filter(x)) { 5: yield return x; 6: } 7: } 8: } 9: 10: static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) { 11: foreach (var x in source) { 12: yield return selector(x); 13: } 14: } 15: } The creation of the extension method makes the syntax much cleaner as shown below. We can write as many extension methods as we want and keep on chaining them using this technique. 1: var formattedEmployees = employees 2: .Where(emp => emp.ID % 2 == 0) 3: .Select (emp => new EmployeeFormatted { ID = emp.ID, FullName = emp.LastName + ", " + emp.FirstName }); Making these changes and running our code produces the same result. 1: using System; 2: using System.Collections.Generic; 3:  4: public class Program 5: { 6: [STAThread] 7: static void Main(string[] args) 8: { 9: var employees = new List<Employee> { 10: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 11: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 12: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 13: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 14: }; 15:  16: var formattedEmployees = employees 17: .Where(emp => emp.ID % 2 == 0) 18: .Select (emp => 19: new EmployeeFormatted { 20: ID = emp.ID, 21: FullName = emp.LastName + ", " + emp.FirstName 22: } 23: ); 24:  25: foreach (EmployeeFormatted emp in formattedEmployees) { 26: Console.WriteLine("ID {0} Full_Name {1}", 27: emp.ID, emp.FullName); 28: } 29: Console.ReadLine(); 30: } 31: } 32:  33: public static class MyExtensionMethods { 34: static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> filter) { 35: foreach (var x in source) { 36: if (filter(x)) { 37: yield return x; 38: } 39: } 40: } 41: 42: static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) { 43: foreach (var x in source) { 44: yield return selector(x); 45: } 46: } 47: } 48:  49: public class Employee { 50: public int ID { get; set;} 51: public string FirstName { get; set;} 52: public string LastName {get; set;} 53: public string Country { get; set; } 54: } 55:  56: public class EmployeeFormatted { 57: public int ID { get; set; } 58: public string FullName {get; set;} 59: } Let’s change our code to return a collection of anonymous types and get rid of the EmployeeFormatted type. We see that the code produces the same output. 1: using System; 2: using System.Collections.Generic; 3:  4: public class Program 5: { 6: [STAThread] 7: static void Main(string[] args) 8: { 9: var employees = new List<Employee> { 10: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 11: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 12: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 13: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 14: }; 15:  16: var formattedEmployees = employees 17: .Where(emp => emp.ID % 2 == 0) 18: .Select (emp => 19: new { 20: ID = emp.ID, 21: FullName = emp.LastName + ", " + emp.FirstName 22: } 23: ); 24:  25: foreach (var emp in formattedEmployees) { 26: Console.WriteLine("ID {0} Full_Name {1}", 27: emp.ID, emp.FullName); 28: } 29: Console.ReadLine(); 30: } 31: } 32:  33: public static class MyExtensionMethods { 34: public static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> filter) { 35: foreach (var x in source) { 36: if (filter(x)) { 37: yield return x; 38: } 39: } 40: } 41: 42: public static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) { 43: foreach (var x in source) { 44: yield return selector(x); 45: } 46: } 47: } 48:  49: public class Employee { 50: public int ID { get; set;} 51: public string FirstName { get; set;} 52: public string LastName {get; set;} 53: public string Country { get; set; } 54: } To be more expressive, C# allows us to write our extension method calls as a query expression. Line 16 can be rewritten a query expression like so: 1: var formattedEmployees = from emp in employees 2: where emp.ID % 2 == 0 3: select new { 4: ID = emp.ID, 5: FullName = emp.LastName + ", " + emp.FirstName 6: }; When the compiler encounters an expression like the above, it simply rewrites it as calls to our extension methods.  So far we have been using our extension methods. The System.Linq namespace contains several extension methods for objects that implement the IEnumerable<T>. You can see a listing of these methods in the Enumerable class in the System.Linq namespace. Let’s get rid of our extension methods (which I purposefully wrote to be of the same signature as the ones in the Enumerable class) and use the ones provided in the Enumerable class. Our final code is shown below: 1: using System; 2: using System.Collections.Generic; 3: using System.Linq; //Added 4:  5: public class Program 6: { 7: [STAThread] 8: static void Main(string[] args) 9: { 10: var employees = new List<Employee> { 11: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 12: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 13: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 14: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 15: }; 16:  17: var formattedEmployees = from emp in employees 18: where emp.ID % 2 == 0 19: select new { 20: ID = emp.ID, 21: FullName = emp.LastName + ", " + emp.FirstName 22: }; 23:  24: foreach (var emp in formattedEmployees) { 25: Console.WriteLine("ID {0} Full_Name {1}", 26: emp.ID, emp.FullName); 27: } 28: Console.ReadLine(); 29: } 30: } 31:  32: public class Employee { 33: public int ID { get; set;} 34: public string FirstName { get; set;} 35: public string LastName {get; set;} 36: public string Country { get; set; } 37: } 38:  39: public class EmployeeFormatted { 40: public int ID { get; set; } 41: public string FullName {get; set;} 42: } This post has shown you a basic overview of LINQ to Objects work by showning you how an expression is converted to a sequence of calls to extension methods when working directly with objects. It gets more interesting when working with LINQ to SQL where an expression tree is constructed – an in memory data representation of the expression. The C# compiler compiles these expressions into code that builds an expression tree at runtime. The provider can then traverse the expression tree and generate the appropriate SQL query. You can read more about expression trees in this MSDN article.

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• mac, netbeans 6.8, c++, sdl, opengl: compilation problems

  - by ufk

  Hiya. I'm trying to properly compile a c++ opengl+sdl application using netbeans 6.8 under Snow Leopard 64-bit. I have libSDL 1.2.14 installed using macports. The script that I try to compile is the following: #ifdef WIN32 #define WIN32_LEAN_AND_MEAN #include <windows.h> #endif #if defined(__APPLE__) && defined(__MACH__) #include <OpenGL/gl.h> // Header File For The OpenGL32 Library #include <OpenGL/glu.h> // Header File For The GLu32 Library #else #include <GL/gl.h> // Header File For The OpenGL32 Library #include <GL/glu.h> // Header File For The GLu32 Library #endif #include "sdl/SDL.h" #include <stdio.h> #include <unistd.h> #include "SDL/SDL_main.h" SDL_Surface *screen=NULL; GLfloat rtri; // Angle For The Triangle ( NEW ) GLfloat rquad; // Angle For The Quad ( NEW ) void InitGL(int Width, int Height) // We call this right after our OpenGL window is created. { glViewport(0, 0, Width, Height); glClearColor(0.0f, 0.0f, 0.0f, 0.0f); // This Will Clear The Background Color To Black glClearDepth(1.0); // Enables Clearing Of The Depth Buffer glDepthFunc(GL_LESS); // The Type Of Depth Test To Do glEnable(GL_DEPTH_TEST); // Enables Depth Testing glShadeModel(GL_SMOOTH); // Enables Smooth Color Shading glMatrixMode(GL_PROJECTION); glLoadIdentity(); // Reset The Projection Matrix gluPerspective(45.0f,(GLfloat)Width/(GLfloat)Height,0.1f,100.0f); // Calculate The Aspect Ratio Of The Window glMatrixMode(GL_MODELVIEW); } /* The main drawing function. */ int DrawGLScene() { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear The Screen And The Depth Buffer glLoadIdentity(); // Reset The View glTranslatef(-1.5f,0.0f,-6.0f); // Move Left 1.5 Units And Into The Screen 6.0 glRotatef(rtri,0.0f,1.0f,0.0f); // Rotate The Triangle On The Y axis ( NEW ) // draw a triangle glBegin(GL_TRIANGLES); // Begin Drawing Triangles glColor3f(1.0f,0.0f,0.0f); // Red glVertex3f( 0.0f, 1.0f, 0.0f); // Top Of Triangle (Front) glColor3f(0.0f,1.0f,0.0f); // Green glVertex3f(-1.0f,-1.0f, 1.0f); // Left Of Triangle (Front) glColor3f(0.0f,0.0f,1.0f); // Blue glVertex3f( 1.0f,-1.0f, 1.0f); // Right Of Triangle (Front) glColor3f(1.0f,0.0f,0.0f); // Red glVertex3f( 0.0f, 1.0f, 0.0f); // Top Of Triangle (Right) glColor3f(0.0f,0.0f,1.0f); // Blue glVertex3f( 1.0f,-1.0f, 1.0f); // Left Of Triangle (Right) glColor3f(0.0f,1.0f,0.0f); // Green glVertex3f( 1.0f,-1.0f, -1.0f); // Right Of Triangle (Right) glColor3f(1.0f,0.0f,0.0f); // Red glVertex3f( 0.0f, 1.0f, 0.0f); // Top Of Triangle (Back) glColor3f(0.0f,1.0f,0.0f); // Green glVertex3f( 1.0f,-1.0f, -1.0f); // Left Of Triangle (Back) glColor3f(0.0f,0.0f,1.0f); // Blue glVertex3f(-1.0f,-1.0f, -1.0f); // Right Of Triangle (Back) glColor3f(1.0f,0.0f,0.0f); // Red glVertex3f( 0.0f, 1.0f, 0.0f); // Top Of Triangle (Left) glColor3f(0.0f,0.0f,1.0f); // Blue glVertex3f(-1.0f,-1.0f,-1.0f); // Left Of Triangle (Left) glColor3f(0.0f,1.0f,0.0f); // Green glVertex3f(-1.0f,-1.0f, 1.0f); // Right Of Triangle (Left) glEnd(); glLoadIdentity(); // Reset The Current Modelview Matrix glTranslatef(1.5f,0.0f,-7.0f); // Move Right 1.5 Units And Into The Screen 6.0 glRotatef(rquad,1.0f,0.0f,0.0f); // Rotate The Quad On The X axis ( NEW ) glBegin(GL_QUADS); // Start Drawing Quads glColor3f(0.0f,1.0f,0.0f); // Set The Color To Green glVertex3f( 1.0f, 1.0f,-1.0f); // Top Right Of The Quad (Top) glVertex3f(-1.0f, 1.0f,-1.0f); // Top Left Of The Quad (Top) glVertex3f(-1.0f, 1.0f, 1.0f); // Bottom Left Of The Quad (Top) glVertex3f( 1.0f, 1.0f, 1.0f); // Bottom Right Of The Quad (Top) glColor3f(1.0f,0.5f,0.0f); // Set The Color To Orange glVertex3f( 1.0f,-1.0f, 1.0f); // Top Right Of The Quad (Bottom) glVertex3f(-1.0f,-1.0f, 1.0f); // Top Left Of The Quad (Bottom) glVertex3f(-1.0f,-1.0f,-1.0f); // Bottom Left Of The Quad (Bottom) glVertex3f( 1.0f,-1.0f,-1.0f); // Bottom Right Of The Quad (Bottom) glColor3f(1.0f,0.0f,0.0f); // Set The Color To Red glVertex3f( 1.0f, 1.0f, 1.0f); // Top Right Of The Quad (Front) glVertex3f(-1.0f, 1.0f, 1.0f); // Top Left Of The Quad (Front) glVertex3f(-1.0f,-1.0f, 1.0f); // Bottom Left Of The Quad (Front) glVertex3f( 1.0f,-1.0f, 1.0f); // Bottom Right Of The Quad (Front) glColor3f(1.0f,1.0f,0.0f); // Set The Color To Yellow glVertex3f( 1.0f,-1.0f,-1.0f); // Bottom Left Of The Quad (Back) glVertex3f(-1.0f,-1.0f,-1.0f); // Bottom Right Of The Quad (Back) glVertex3f(-1.0f, 1.0f,-1.0f); // Top Right Of The Quad (Back) glVertex3f( 1.0f, 1.0f,-1.0f); // Top Left Of The Quad (Back) glColor3f(0.0f,0.0f,1.0f); // Set The Color To Blue glVertex3f(-1.0f, 1.0f, 1.0f); // Top Right Of The Quad (Left) glVertex3f(-1.0f, 1.0f,-1.0f); // Top Left Of The Quad (Left) glVertex3f(-1.0f,-1.0f,-1.0f); // Bottom Left Of The Quad (Left) glVertex3f(-1.0f,-1.0f, 1.0f); // Bottom Right Of The Quad (Left) glColor3f(1.0f,0.0f,1.0f); // Set The Color To Violet glVertex3f( 1.0f, 1.0f,-1.0f); // Top Right Of The Quad (Right) glVertex3f( 1.0f, 1.0f, 1.0f); // Top Left Of The Quad (Right) glVertex3f( 1.0f,-1.0f, 1.0f); // Bottom Left Of The Quad (Right) glVertex3f( 1.0f,-1.0f,-1.0f); // Bottom Right Of The Quad (Right) glEnd(); // Done Drawing A Quad rtri+=0.02f; // Increase The Rotation Variable For The Triangle ( NEW ) rquad-=0.015f; // Decrease The Rotation Variable For The Quad ( NEW ) // swap buffers to display, since we're double buffered. SDL_GL_SwapBuffers(); return true; } int main(int argc,char* argv[]) { int done; /*variable to hold the file name of the image to be loaded *In real world error handling code would precede this */ /* Initialize SDL for video output */ if ( SDL_Init(SDL_INIT_VIDEO) < 0 ) { fprintf(stderr, "Unable to initialize SDL: %s\n", SDL_GetError()); exit(1); } atexit(SDL_Quit); /* Create a 640x480 OpenGL screen */ if ( SDL_SetVideoMode(640, 480, 0, SDL_OPENGL) == NULL ) { fprintf(stderr, "Unable to create OpenGL screen: %s\n", SDL_GetError()); SDL_Quit(); exit(2); } SDL_WM_SetCaption("another example",NULL); InitGL(640,480); done=0; while (! done) { DrawGLScene(); SDL_Event event; while ( SDL_PollEvent(&event) ) { if ( event.type == SDL_QUIT ) { done = 1; } if ( event.type == SDL_KEYDOWN ) { if ( event.key.keysym.sym == SDLK_ESCAPE ) { done = 1; } } } } } Under netbeans project properties I configured the following: C++ Compiler: added /usr/X11/include and /opt/local/include to the include directories. Linker: I added the following libraries: /usr/X11/lib/libGL.dylib /usr/X11/lib/libGLU.dylib /opt/local/lib/libSDL.dylib /opt/local/lib/libSDLmain.a Now... before I included SDL_main.h and libSDLMain.a to the project I got an error unknown reference to _main then I read here: http://www.libsdl.org/faq.php?action=listentries&category=7#55 that I need to include SDL_Main.h and to link libSDLMain.so to my project. after doing so, the project still won't compile. this is the Netbeans output: /usr/bin/make -f nbproject/Makefile-Debug.mk SUBPROJECTS= .clean-conf rm -f -r build/Debug rm -f dist/Debug/GNU-MacOSX/opengl2 CLEAN SUCCESSFUL (total time: 79ms) /usr/bin/make -f nbproject/Makefile-Debug.mk SUBPROJECTS= .build-conf /usr/bin/make -f nbproject/Makefile-Debug.mk dist/Debug/GNU-MacOSX/opengl2 mkdir -p build/Debug/GNU-MacOSX rm -f build/Debug/GNU-MacOSX/main.o.d g++ -c -g -I/usr/X11/include -I/opt/local/include -MMD -MP -MF build/Debug/GNU-MacOSX/main.o.d -o build/Debug/GNU-MacOSX/main.o main.cpp mkdir -p dist/Debug/GNU-MacOSX g++ -o dist/Debug/GNU-MacOSX/opengl2 build/Debug/GNU-MacOSX/main.o /opt/local/lib/libIL.dylib /opt/local/lib/libILU.dylib /opt/local/lib/libILUT.dylib /usr/X11/lib/libGL.dylib /usr/X11/lib/libGLU.dylib /opt/local/lib/libSDL.dylib /opt/local/lib/libSDLmain.a Undefined symbols: "_OBJC_CLASS_$_NSMenu", referenced from: __objc_classrefs__DATA@0 in libSDLmain.a(SDLMain.o) "__objc_empty_cache", referenced from: _OBJC_METACLASS_$_SDLMain in libSDLmain.a(SDLMain.o) _OBJC_CLASS_$_SDLMain in libSDLmain.a(SDLMain.o) "_CFBundleGetMainBundle", referenced from: -[SDLMain setupWorkingDirectory:] in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) "_CFURLGetFileSystemRepresentation", referenced from: -[SDLMain setupWorkingDirectory:] in libSDLmain.a(SDLMain.o) "_NSApp", referenced from: _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) "_OBJC_CLASS_$_NSProcessInfo", referenced from: __objc_classrefs__DATA@0 in libSDLmain.a(SDLMain.o) "_CFURLCreateCopyDeletingLastPathComponent", referenced from: -[SDLMain setupWorkingDirectory:] in libSDLmain.a(SDLMain.o) "_NSAllocateMemoryPages", referenced from: -[NSString(ReplaceSubString) stringByReplacingRange:with:] in libSDLmain.a(SDLMain.o) "___CFConstantStringClassReference", referenced from: cfstring=CFBundleName in libSDLmain.a(SDLMain.o) cfstring= in libSDLmain.a(SDLMain.o) cfstring=About in libSDLmain.a(SDLMain.o) cfstring=Hide in libSDLmain.a(SDLMain.o) cfstring=h in libSDLmain.a(SDLMain.o) cfstring=Hide Others in libSDLmain.a(SDLMain.o) cfstring=Show All in libSDLmain.a(SDLMain.o) cfstring=Quit in libSDLmain.a(SDLMain.o) cfstring=q in libSDLmain.a(SDLMain.o) cfstring=Window in libSDLmain.a(SDLMain.o) cfstring=m in libSDLmain.a(SDLMain.o) cfstring=Minimize in libSDLmain.a(SDLMain.o) "_OBJC_CLASS_$_NSAutoreleasePool", referenced from: __objc_classrefs__DATA@0 in libSDLmain.a(SDLMain.o) "_CPSEnableForegroundOperation", referenced from: _main in libSDLmain.a(SDLMain.o) "_CPSGetCurrentProcess", referenced from: _main in libSDLmain.a(SDLMain.o) "_CFBundleCopyBundleURL", referenced from: -[SDLMain setupWorkingDirectory:] in libSDLmain.a(SDLMain.o) "_NSDeallocateMemoryPages", referenced from: -[NSString(ReplaceSubString) stringByReplacingRange:with:] in libSDLmain.a(SDLMain.o) "_OBJC_CLASS_$_NSApplication", referenced from: l_OBJC_$_CATEGORY_NSApplication_$_SDLApplication in libSDLmain.a(SDLMain.o) __objc_classrefs__DATA@0 in libSDLmain.a(SDLMain.o) "_CPSSetFrontProcess", referenced from: _main in libSDLmain.a(SDLMain.o) "_OBJC_CLASS_$_NSString", referenced from: l_OBJC_$_CATEGORY_NSString_$_ReplaceSubString in libSDLmain.a(SDLMain.o) __objc_classrefs__DATA@0 in libSDLmain.a(SDLMain.o) "_OBJC_CLASS_$_NSObject", referenced from: _OBJC_CLASS_$_SDLMain in libSDLmain.a(SDLMain.o) "_CFBundleGetInfoDictionary", referenced from: _main in libSDLmain.a(SDLMain.o) "_CFRelease", referenced from: -[SDLMain setupWorkingDirectory:] in libSDLmain.a(SDLMain.o) -[SDLMain setupWorkingDirectory:] in libSDLmain.a(SDLMain.o) "__objc_empty_vtable", referenced from: _OBJC_METACLASS_$_SDLMain in libSDLmain.a(SDLMain.o) _OBJC_CLASS_$_SDLMain in libSDLmain.a(SDLMain.o) "_OBJC_CLASS_$_NSMenuItem", referenced from: __objc_classrefs__DATA@0 in libSDLmain.a(SDLMain.o) "_objc_msgSend", referenced from: -[SDLMain application:openFile:] in libSDLmain.a(SDLMain.o) -[SDLMain applicationDidFinishLaunching:] in libSDLmain.a(SDLMain.o) -[NSString(ReplaceSubString) stringByReplacingRange:with:] in libSDLmain.a(SDLMain.o) -[NSString(ReplaceSubString) stringByReplacingRange:with:] in libSDLmain.a(SDLMain.o) -[NSString(ReplaceSubString) stringByReplacingRange:with:] in libSDLmain.a(SDLMain.o) -[NSString(ReplaceSubString) stringByReplacingRange:with:] in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) _main in libSDLmain.a(SDLMain.o) "_OBJC_METACLASS_$_NSObject", referenced from: _OBJC_METACLASS_$_SDLMain in libSDLmain.a(SDLMain.o) _OBJC_METACLASS_$_SDLMain in libSDLmain.a(SDLMain.o) "_objc_msgSend_fixup", referenced from: l_objc_msgSend_fixup_objectForKey_ in libSDLmain.a(SDLMain.o) l_objc_msgSend_fixup_length in libSDLmain.a(SDLMain.o) l_objc_msgSend_fixup_alloc in libSDLmain.a(SDLMain.o) l_objc_msgSend_fixup_release in libSDLmain.a(SDLMain.o) ld: symbol(s) not found collect2: ld returned 1 exit status make[2]: *** [dist/Debug/GNU-MacOSX/opengl2] Error 1 make[1]: *** [.build-conf] Error 2 make: *** [.build-impl] Error 2 BUILD FAILED (exit value 2, total time: 263ms) any ideas? thanks a lot!

  Read the article

• opengl problem works on droid but not droid eris and others.

  - by nathan

  This GlRenderer works fine on the moto droid, but does not work well at all on droid eris or other android phones does anyone know why? package com.ntu.way2fungames.spacehockeybase; import java.io.DataInputStream; import java.io.IOException; import java.nio.Buffer; import java.nio.FloatBuffer; import javax.microedition.khronos.egl.EGLConfig; import javax.microedition.khronos.opengles.GL10; import com.ntu.way2fungames.LoadFloatArray; import com.ntu.way2fungames.OGLTriReader; import android.content.res.AssetManager; import android.content.res.Resources; import android.opengl.GLU; import android.opengl.GLSurfaceView.Renderer; import android.os.Handler; import android.os.Message; public class GlRenderer extends Thread implements Renderer { private float drawArray[]; private float yoff; private float yoff2; private long lastRenderTime; private float[] yoffs= new float[10]; int Width; int Height; private float[] pixelVerts = new float[] { +.0f,+.0f,2, +.5f,+.5f,0, +.5f,-.5f,0, +.0f,+.0f,2, +.5f,-.5f,0, -.5f,-.5f,0, +.0f,+.0f,2, -.5f,-.5f,0, -.5f,+.5f,0, +.0f,+.0f,2, -.5f,+.5f,0, +.5f,+.5f,0, }; @Override public void run() { } private float[] arenaWalls = new float[] { 8.00f,2.00f,1f,2f,2f,1f,2.00f,8.00f,1f,8.00f,2.00f,1f,2.00f,8.00f,1f,8.00f,8.00f,1f, 2.00f,8.00f,1f,2f,2f,1f,0.00f,0.00f,0f,2.00f,8.00f,1f,0.00f,0.00f,0f,0.00f,10.00f,0f, 8.00f,8.00f,1f,2.00f,8.00f,1f,0.00f,10.00f,0f,8.00f,8.00f,1f,0.00f,10.00f,0f,10.00f,10.00f,0f, 2f,2f,1f,8.00f,2.00f,1f,10.00f,0.00f,0f,2f,2f,1f,10.00f,0.00f,0f,0.00f,0.00f,0f, 8.00f,2.00f,1f,8.00f,8.00f,1f,10.00f,10.00f,0f,8.00f,2.00f,1f,10.00f,10.00f,0f,10.00f,0.00f,0f, 10.00f,10.00f,0f,0.00f,10.00f,0f,0.00f,0.00f,0f,10.00f,10.00f,0f,0.00f,0.00f,0f,10.00f,0.00f,0f, 8.00f,6.00f,1f,8.00f,4.00f,1f,122f,4.00f,1f,8.00f,6.00f,1f,122f,4.00f,1f,122f,6.00f,1f, 8.00f,6.00f,1f,122f,6.00f,1f,120f,7.00f,0f,8.00f,6.00f,1f,120f,7.00f,0f,10.00f,7.00f,0f, 122f,4.00f,1f,8.00f,4.00f,1f,10.00f,3.00f,0f,122f,4.00f,1f,10.00f,3.00f,0f,120f,3.00f,0f, 480f,10.00f,0f,470f,10.00f,0f,470f,0.00f,0f,480f,10.00f,0f,470f,0.00f,0f,480f,0.00f,0f, 478f,2.00f,1f,478f,8.00f,1f,480f,10.00f,0f,478f,2.00f,1f,480f,10.00f,0f,480f,0.00f,0f, 472f,2f,1f,478f,2.00f,1f,480f,0.00f,0f,472f,2f,1f,480f,0.00f,0f,470f,0.00f,0f, 478f,8.00f,1f,472f,8.00f,1f,470f,10.00f,0f,478f,8.00f,1f,470f,10.00f,0f,480f,10.00f,0f, 472f,8.00f,1f,472f,2f,1f,470f,0.00f,0f,472f,8.00f,1f,470f,0.00f,0f,470f,10.00f,0f, 478f,2.00f,1f,472f,2f,1f,472f,8.00f,1f,478f,2.00f,1f,472f,8.00f,1f,478f,8.00f,1f, 478f,846f,1f,472f,846f,1f,472f,852f,1f,478f,846f,1f,472f,852f,1f,478f,852f,1f, 472f,852f,1f,472f,846f,1f,470f,844f,0f,472f,852f,1f,470f,844f,0f,470f,854f,0f, 478f,852f,1f,472f,852f,1f,470f,854f,0f,478f,852f,1f,470f,854f,0f,480f,854f,0f, 472f,846f,1f,478f,846f,1f,480f,844f,0f,472f,846f,1f,480f,844f,0f,470f,844f,0f, 478f,846f,1f,478f,852f,1f,480f,854f,0f,478f,846f,1f,480f,854f,0f,480f,844f,0f, 480f,854f,0f,470f,854f,0f,470f,844f,0f,480f,854f,0f,470f,844f,0f,480f,844f,0f, 10.00f,854f,0f,0.00f,854f,0f,0.00f,844f,0f,10.00f,854f,0f,0.00f,844f,0f,10.00f,844f,0f, 8.00f,846f,1f,8.00f,852f,1f,10.00f,854f,0f,8.00f,846f,1f,10.00f,854f,0f,10.00f,844f,0f, 2f,846f,1f,8.00f,846f,1f,10.00f,844f,0f,2f,846f,1f,10.00f,844f,0f,0.00f,844f,0f, 8.00f,852f,1f,2.00f,852f,1f,0.00f,854f,0f,8.00f,852f,1f,0.00f,854f,0f,10.00f,854f,0f, 2.00f,852f,1f,2f,846f,1f,0.00f,844f,0f,2.00f,852f,1f,0.00f,844f,0f,0.00f,854f,0f, 8.00f,846f,1f,2f,846f,1f,2.00f,852f,1f,8.00f,846f,1f,2.00f,852f,1f,8.00f,852f,1f, 6f,846f,1f,4f,846f,1f,4f,8f,1f,6f,846f,1f,4f,8f,1f,6f,8f,1f, 6f,846f,1f,6f,8f,1f,7f,10f,0f,6f,846f,1f,7f,10f,0f,7f,844f,0f, 4f,8f,1f,4f,846f,1f,3f,844f,0f,4f,8f,1f,3f,844f,0f,3f,10f,0f, 474f,8f,1f,474f,846f,1f,473f,844f,0f,474f,8f,1f,473f,844f,0f,473f,10f,0f, 476f,846f,1f,476f,8f,1f,477f,10f,0f,476f,846f,1f,477f,10f,0f,477f,844f,0f, 476f,846f,1f,474f,846f,1f,474f,8f,1f,476f,846f,1f,474f,8f,1f,476f,8f,1f, 130f,10.00f,0f,120f,10.00f,0f,120f,0.00f,0f,130f,10.00f,0f,120f,0.00f,0f,130f,0.00f,0f, 128f,2.00f,1f,128f,8.00f,1f,130f,10.00f,0f,128f,2.00f,1f,130f,10.00f,0f,130f,0.00f,0f, 122f,2f,1f,128f,2.00f,1f,130f,0.00f,0f,122f,2f,1f,130f,0.00f,0f,120f,0.00f,0f, 128f,8.00f,1f,122f,8.00f,1f,120f,10.00f,0f,128f,8.00f,1f,120f,10.00f,0f,130f,10.00f,0f, 122f,8.00f,1f,122f,2f,1f,120f,0.00f,0f,122f,8.00f,1f,120f,0.00f,0f,120f,10.00f,0f, 128f,2.00f,1f,122f,2f,1f,122f,8.00f,1f,128f,2.00f,1f,122f,8.00f,1f,128f,8.00f,1f, 352f,8.00f,1f,358f,8.00f,1f,358f,2.00f,1f,352f,8.00f,1f,358f,2.00f,1f,352f,2.00f,1f, 358f,2.00f,1f,358f,8.00f,1f,360f,10.00f,0f,358f,2.00f,1f,360f,10.00f,0f,360f,0.00f,0f, 352f,2.00f,1f,358f,2.00f,1f,360f,0.00f,0f,352f,2.00f,1f,360f,0.00f,0f,350f,0.00f,0f, 358f,8.00f,1f,352f,8.00f,1f,350f,10.00f,0f,358f,8.00f,1f,350f,10.00f,0f,360f,10.00f,0f, 352f,8.00f,1f,352f,2.00f,1f,350f,0.00f,0f,352f,8.00f,1f,350f,0.00f,0f,350f,10.00f,0f, 350f,0.00f,0f,360f,0.00f,0f,360f,10.00f,0f,350f,0.00f,0f,360f,10.00f,0f,350f,10.00f,0f, 358f,6.00f,1f,472f,6.00f,1f,470f,7.00f,0f,358f,6.00f,1f,470f,7.00f,0f,360f,7.00f,0f, 472f,4.00f,1f,358f,4.00f,1f,360f,3.00f,0f,472f,4.00f,1f,360f,3.00f,0f,470f,3.00f,0f, 472f,4.00f,1f,472f,6.00f,1f,358f,6.00f,1f,472f,4.00f,1f,358f,6.00f,1f,358f,4.00f,1f, 472f,848f,1f,472f,850f,1f,358f,850f,1f,472f,848f,1f,358f,850f,1f,358f,848f,1f, 472f,848f,1f,358f,848f,1f,360f,847f,0f,472f,848f,1f,360f,847f,0f,470f,847f,0f, 358f,850f,1f,472f,850f,1f,470f,851f,0f,358f,850f,1f,470f,851f,0f,360f,851f,0f, 350f,844f,0f,360f,844f,0f,360f,854f,0f,350f,844f,0f,360f,854f,0f,350f,854f,0f, 352f,852f,1f,352f,846f,1f,350f,844f,0f,352f,852f,1f,350f,844f,0f,350f,854f,0f, 358f,852f,1f,352f,852f,1f,350f,854f,0f,358f,852f,1f,350f,854f,0f,360f,854f,0f, 352f,846f,1f,358f,846f,1f,360f,844f,0f,352f,846f,1f,360f,844f,0f,350f,844f,0f, 358f,846f,1f,358f,852f,1f,360f,854f,0f,358f,846f,1f,360f,854f,0f,360f,844f,0f, 352f,852f,1f,358f,852f,1f,358f,846f,1f,352f,852f,1f,358f,846f,1f,352f,846f,1f, 128f,846f,1f,122f,846f,1f,122f,852f,1f,128f,846f,1f,122f,852f,1f,128f,852f,1f, 122f,852f,1f,122f,846f,1f,120f,844f,0f,122f,852f,1f,120f,844f,0f,120f,854f,0f, 128f,852f,1f,122f,852f,1f,120f,854f,0f,128f,852f,1f,120f,854f,0f,130f,854f,0f, 122f,846f,1f,128f,846f,1f,130f,844f,0f,122f,846f,1f,130f,844f,0f,120f,844f,0f, 128f,846f,1f,128f,852f,1f,130f,854f,0f,128f,846f,1f,130f,854f,0f,130f,844f,0f, 130f,854f,0f,120f,854f,0f,120f,844f,0f,130f,854f,0f,120f,844f,0f,130f,844f,0f, 122f,848f,1f,8f,848f,1f,10f,847f,0f,122f,848f,1f,10f,847f,0f,120f,847f,0f, 8f,850f,1f,122f,850f,1f,120f,851f,0f,8f,850f,1f,120f,851f,0f,10f,851f,0f, 8f,850f,1f,8f,848f,1f,122f,848f,1f,8f,850f,1f,122f,848f,1f,122f,850f,1f, 10f,847f,0f,120f,847f,0f,124.96f,829.63f,-0.50f,10f,847f,0f,124.96f,829.63f,-0.50f,19.51f,829.63f,-0.50f, 130f,844f,0f,130f,854f,0f,134.55f,836.34f,-0.50f,130f,844f,0f,134.55f,836.34f,-0.50f,134.55f,826.76f,-0.50f, 350f,844f,0f,350f,854f,0f,345.45f,836.34f,-0.50f,350f,844f,0f,345.45f,836.34f,-0.50f,345.45f,826.76f,-0.50f, 360f,847f,0f,470f,847f,0f,460.49f,829.63f,-0.50f,360f,847f,0f,460.49f,829.63f,-0.50f,355.04f,829.63f,-0.50f, 470f,7.00f,0f,360f,7.00f,0f,355.04f,24.37f,-0.50f,470f,7.00f,0f,355.04f,24.37f,-0.50f,460.49f,24.37f,-0.50f, 350f,10.00f,0f,350f,0.00f,0f,345.45f,17.66f,-0.50f,350f,10.00f,0f,345.45f,17.66f,-0.50f,345.45f,27.24f,-0.50f, 130f,10.00f,0f,130f,0.00f,0f,134.55f,17.66f,-0.50f,130f,10.00f,0f,134.55f,17.66f,-0.50f,134.55f,27.24f,-0.50f, 473f,844f,0f,473f,10f,0f,463.36f,27.24f,-0.50f,473f,844f,0f,463.36f,27.24f,-0.50f,463.36f,826.76f,-0.50f, 7f,10f,0f,7f,844f,0f,16.64f,826.76f,-0.50f,7f,10f,0f,16.64f,826.76f,-0.50f,16.64f,27.24f,-0.50f, 120f,7.00f,0f,10.00f,7.00f,0f,19.51f,24.37f,-0.50f,120f,7.00f,0f,19.51f,24.37f,-0.50f,124.96f,24.37f,-0.50f, 120f,7.00f,0f,130f,10.00f,0f,134.55f,27.24f,-0.50f,120f,7.00f,0f,134.55f,27.24f,-0.50f,124.96f,24.37f,-0.50f, 10.00f,7.00f,0f,7f,10f,0f,16.64f,27.24f,-0.50f,10.00f,7.00f,0f,16.64f,27.24f,-0.50f,19.51f,24.37f,-0.50f, 350f,10.00f,0f,360f,7.00f,0f,355.04f,24.37f,-0.50f,350f,10.00f,0f,355.04f,24.37f,-0.50f,345.45f,27.24f,-0.50f, 473f,10f,0f,470f,7.00f,0f,460.49f,24.37f,-0.50f,473f,10f,0f,460.49f,24.37f,-0.50f,463.36f,27.24f,-0.50f, 473f,844f,0f,470f,847f,0f,460.49f,829.63f,-0.50f,473f,844f,0f,460.49f,829.63f,-0.50f,463.36f,826.76f,-0.50f, 360f,847f,0f,350f,844f,0f,345.45f,826.76f,-0.50f,360f,847f,0f,345.45f,826.76f,-0.50f,355.04f,829.63f,-0.50f, 130f,844f,0f,120f,847f,0f,124.96f,829.63f,-0.50f,130f,844f,0f,124.96f,829.63f,-0.50f,134.55f,826.76f,-0.50f, 7f,844f,0f,10f,847f,0f,19.51f,829.63f,-0.50f,7f,844f,0f,19.51f,829.63f,-0.50f,16.64f,826.76f,-0.50f, 19.51f,829.63f,-0.50f,124.96f,829.63f,-0.50f,136.47f,789.37f,-2f,19.51f,829.63f,-0.50f,136.47f,789.37f,-2f,41.56f,789.37f,-2f, 134.55f,826.76f,-0.50f,134.55f,836.34f,-0.50f,145.09f,795.41f,-2f,134.55f,826.76f,-0.50f,145.09f,795.41f,-2f,145.09f,786.78f,-2f, 345.45f,826.76f,-0.50f,345.45f,836.34f,-0.50f,334.91f,795.41f,-2f,345.45f,826.76f,-0.50f,334.91f,795.41f,-2f,334.91f,786.78f,-2f, 355.04f,829.63f,-0.50f,460.49f,829.63f,-0.50f,438.44f,789.37f,-2f,355.04f,829.63f,-0.50f,438.44f,789.37f,-2f,343.53f,789.37f,-2f, 460.49f,24.37f,-0.50f,355.04f,24.37f,-0.50f,343.53f,64.63f,-2f,460.49f,24.37f,-0.50f,343.53f,64.63f,-2f,438.44f,64.63f,-2f, 345.45f,27.24f,-0.50f,345.45f,17.66f,-0.50f,334.91f,58.59f,-2f,345.45f,27.24f,-0.50f,334.91f,58.59f,-2f,334.91f,67.22f,-2f, 134.55f,27.24f,-0.50f,134.55f,17.66f,-0.50f,145.09f,58.59f,-2f,134.55f,27.24f,-0.50f,145.09f,58.59f,-2f,145.09f,67.22f,-2f, 463.36f,826.76f,-0.50f,463.36f,27.24f,-0.50f,441.03f,67.22f,-2f,463.36f,826.76f,-0.50f,441.03f,67.22f,-2f,441.03f,786.78f,-2f, 16.64f,27.24f,-0.50f,16.64f,826.76f,-0.50f,38.97f,786.78f,-2f,16.64f,27.24f,-0.50f,38.97f,786.78f,-2f,38.97f,67.22f,-2f, 124.96f,24.37f,-0.50f,19.51f,24.37f,-0.50f,41.56f,64.63f,-2f,124.96f,24.37f,-0.50f,41.56f,64.63f,-2f,136.47f,64.63f,-2f, 124.96f,24.37f,-0.50f,134.55f,27.24f,-0.50f,145.09f,67.22f,-2f,124.96f,24.37f,-0.50f,145.09f,67.22f,-2f,136.47f,64.63f,-2f, 19.51f,24.37f,-0.50f,16.64f,27.24f,-0.50f,38.97f,67.22f,-2f,19.51f,24.37f,-0.50f,38.97f,67.22f,-2f,41.56f,64.63f,-2f, 345.45f,27.24f,-0.50f,355.04f,24.37f,-0.50f,343.53f,64.63f,-2f,345.45f,27.24f,-0.50f,343.53f,64.63f,-2f,334.91f,67.22f,-2f, 463.36f,27.24f,-0.50f,460.49f,24.37f,-0.50f,438.44f,64.63f,-2f,463.36f,27.24f,-0.50f,438.44f,64.63f,-2f,441.03f,67.22f,-2f, 463.36f,826.76f,-0.50f,460.49f,829.63f,-0.50f,438.44f,789.37f,-2f,463.36f,826.76f,-0.50f,438.44f,789.37f,-2f,441.03f,786.78f,-2f, 355.04f,829.63f,-0.50f,345.45f,826.76f,-0.50f,334.91f,786.78f,-2f,355.04f,829.63f,-0.50f,334.91f,786.78f,-2f,343.53f,789.37f,-2f, 134.55f,826.76f,-0.50f,124.96f,829.63f,-0.50f,136.47f,789.37f,-2f,134.55f,826.76f,-0.50f,136.47f,789.37f,-2f,145.09f,786.78f,-2f, 16.64f,826.76f,-0.50f,19.51f,829.63f,-0.50f,41.56f,789.37f,-2f,16.64f,826.76f,-0.50f,41.56f,789.37f,-2f,38.97f,786.78f,-2f, }; private float[] backgroundData = new float[] { // # ,Scale, Speed, 300 , 1.05f, .001f, 150 , 1.07f, .002f, 075 , 1.10f, .003f, 040 , 1.12f, .006f, 20 , 1.15f, .012f, 10 , 1.25f, .025f, 05 , 1.50f, .050f, 3 , 2.00f, .100f, 2 , 3.00f, .200f, }; private float[] triangleCoords = new float[] { 0, -25, 0, -.75f, -1, 0, +.75f, -1, 0, 0, +2, 0, -.99f, -1, 0, .99f, -1, 0, }; private float[] triangleColors = new float[] { 1.0f, 1.0f, 1.0f, 0.05f, 1.0f, 1.0f, 1.0f, 0.5f, 1.0f, 1.0f, 1.0f, 0.5f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 0.5f, 1.0f, 1.0f, 1.0f, 0.5f, }; private float[] drawArray2; private FloatBuffer drawBuffer2; private float[] colorArray2; private static FloatBuffer colorBuffer; private static FloatBuffer triangleBuffer; private static FloatBuffer quadBuffer; private static FloatBuffer drawBuffer; private float[] backgroundVerts; private FloatBuffer backgroundVertsWrapped; private float[] backgroundColors; private Buffer backgroundColorsWraped; private FloatBuffer backgroundColorsWrapped; private FloatBuffer arenaWallsWrapped; private FloatBuffer arenaColorsWrapped; private FloatBuffer arena2VertsWrapped; private FloatBuffer arena2ColorsWrapped; private long wallHitStartTime; private int wallHitDrawTime; private FloatBuffer pixelVertsWrapped; private float[] wallHit; private FloatBuffer pixelColorsWrapped; //private float[] pitVerts; private Resources lResources; private FloatBuffer pitVertsWrapped; private FloatBuffer pitColorsWrapped; private boolean arena2; private long lastStartTime; private long startTime; private int state=1; private long introEndTime; protected long introTotalTime =8000; protected long introStartTime; private boolean initDone= false; private static int stateIntro = 0; private static int stateGame = 1; public GlRenderer(spacehockey nspacehockey) { lResources = nspacehockey.getResources(); nspacehockey.SetHandlerToGLRenderer(new Handler() { @Override public void handleMessage(Message m) { if (m.what ==0){ wallHit = m.getData().getFloatArray("wall hit"); wallHitStartTime =System.currentTimeMillis(); wallHitDrawTime = 1000; }else if (m.what ==1){ //state = stateIntro; introEndTime= System.currentTimeMillis()+introTotalTime ; introStartTime = System.currentTimeMillis(); } }}); } public void onSurfaceCreated(GL10 gl, EGLConfig config) { gl.glShadeModel(GL10.GL_SMOOTH); gl.glClearColor(.01f, .01f, .01f, .1f); gl.glClearDepthf(1.0f); gl.glEnable(GL10.GL_DEPTH_TEST); gl.glDepthFunc(GL10.GL_LEQUAL); gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_NICEST); } private float SumOfStrideI(float[] data, int offset, int stride) { int sum= 0; for (int i=offset;i<data.length-1;i=i+stride){ sum = (int) (data[i]+sum); } return sum; } public void onDrawFrame(GL10 gl) { if (state== stateIntro){DrawIntro(gl);} if (state== stateGame){DrawGame(gl);} } private void DrawIntro(GL10 gl) { startTime = System.currentTimeMillis(); if (startTime< introEndTime){ float ptd = (float)(startTime- introStartTime)/(float)introTotalTime; float ptl = 1-ptd; gl.glClear(GL10.GL_COLOR_BUFFER_BIT);//dont move gl.glMatrixMode(GL10.GL_MODELVIEW); int setVertOff = 0; gl.glEnableClientState(GL10.GL_VERTEX_ARRAY); gl.glEnableClientState(GL10.GL_COLOR_ARRAY); gl.glColorPointer(4, GL10.GL_FLOAT, 0, backgroundColorsWrapped); for (int i = 0; i < backgroundData.length / 3; i = i + 1) { int setoff = i * 3; int setVertLen = (int) backgroundData[setoff]; yoffs[i] = (backgroundData[setoff + 2]*(90+(ptl*250))) + yoffs[i]; if (yoffs[i] > Height) {yoffs[i] = 0;} gl.glPushMatrix(); //gl.glTranslatef(0, -(Height/2), 0); //gl.glScalef(1f, 1f+(ptl*2), 1f); //gl.glTranslatef(0, +(Height/2), 0); gl.glTranslatef(0, yoffs[i], i+60); gl.glVertexPointer(3, GL10.GL_FLOAT, 0, backgroundVertsWrapped); gl.glDrawArrays(GL10.GL_TRIANGLES, (setVertOff * 2 * 3) - 0, (setVertLen * 2 * 3) - 1); gl.glTranslatef(0, -Height, 0); gl.glDrawArrays(GL10.GL_TRIANGLES, (setVertOff * 2 * 3) - 0, (setVertLen * 2 * 3) - 1); setVertOff = (int) (setVertOff + setVertLen); gl.glPopMatrix(); } gl.glDisableClientState(GL10.GL_VERTEX_ARRAY); gl.glDisableClientState(GL10.GL_COLOR_ARRAY); }else{state = stateGame;} } private void DrawGame(GL10 gl) { lastStartTime = startTime; startTime = System.currentTimeMillis(); long moveTime = startTime-lastStartTime; gl.glClear(GL10.GL_COLOR_BUFFER_BIT);//dont move gl.glMatrixMode(GL10.GL_MODELVIEW); int setVertOff = 0; gl.glEnableClientState(GL10.GL_VERTEX_ARRAY); gl.glEnableClientState(GL10.GL_COLOR_ARRAY); gl.glColorPointer(4, GL10.GL_FLOAT, 0, backgroundColorsWrapped); for (int i = 0; i < backgroundData.length / 3; i = i + 1) { int setoff = i * 3; int setVertLen = (int) backgroundData[setoff]; yoffs[i] = (backgroundData[setoff + 2]*moveTime) + yoffs[i]; if (yoffs[i] > Height) {yoffs[i] = 0;} gl.glPushMatrix(); gl.glTranslatef(0, yoffs[i], i+60); gl.glVertexPointer(3, GL10.GL_FLOAT, 0, backgroundVertsWrapped); gl.glDrawArrays(GL10.GL_TRIANGLES, (setVertOff * 6) - 0, (setVertLen *6) - 1); gl.glTranslatef(0, -Height, 0); gl.glDrawArrays(GL10.GL_TRIANGLES, (setVertOff * 6) - 0, (setVertLen *6) - 1); setVertOff = (int) (setVertOff + setVertLen); gl.glPopMatrix(); } //arena frame gl.glPushMatrix(); gl.glVertexPointer(3, GL10.GL_FLOAT, 0, arenaWallsWrapped); gl.glColorPointer(4, GL10.GL_FLOAT, 0, arenaColorsWrapped); gl.glColor4f(.1f, .5f, 1f, 1f); gl.glTranslatef(0, 0, 50); gl.glDrawArrays(GL10.GL_TRIANGLES, 0, (int)(arenaWalls.length / 3)); gl.glPopMatrix(); //arena2 frame if (arena2 == true){ gl.glLoadIdentity(); gl.glVertexPointer(3, GL10.GL_FLOAT, 0, pitVertsWrapped); gl.glColorPointer(4, GL10.GL_FLOAT, 0, pitColorsWrapped); gl.glTranslatef(0, -Height, 40); gl.glDrawArrays(GL10.GL_TRIANGLES, 0, (int)(pitVertsWrapped.capacity() / 3)); } if (wallHitStartTime != 0) { float timeRemaining = (wallHitStartTime + wallHitDrawTime)-System.currentTimeMillis(); if (timeRemaining>0) { gl.glPushMatrix(); float percentDone = 1-(timeRemaining/wallHitDrawTime); gl.glLoadIdentity(); gl.glVertexPointer(3, GL10.GL_FLOAT, 0, pixelVertsWrapped); gl.glColorPointer(4, GL10.GL_FLOAT, 0, pixelColorsWrapped); gl.glTranslatef(wallHit[0], wallHit[1], 0); gl.glScalef(8, Height*percentDone, 0); gl.glDrawArrays(GL10.GL_TRIANGLES, 0, 12); gl.glPopMatrix(); } else { wallHitStartTime = 0; } } gl.glDisableClientState(GL10.GL_VERTEX_ARRAY); gl.glDisableClientState(GL10.GL_COLOR_ARRAY); } public void init(GL10 gl) { if (arena2 == true) { AssetManager assetManager = lResources.getAssets(); try { // byte[] ba = {111,111}; DataInputStream Dis = new DataInputStream(assetManager .open("arena2.ogl")); pitVertsWrapped = LoadFloatArray.FromDataInputStream(Dis); pitColorsWrapped = MakeFakeLighting(pitVertsWrapped.array(), .25f, .50f, 1f, 200, .5f); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } if ((Height != 854) || (Width != 480)) { arenaWalls = ScaleFloats(arenaWalls, Width / 480f, Height / 854f); } arenaWallsWrapped = FloatBuffer.wrap(arenaWalls); arenaColorsWrapped = MakeFakeLighting(arenaWalls, .03f, .16f, .33f, .33f, 3); pixelVertsWrapped = FloatBuffer.wrap(pixelVerts); pixelColorsWrapped = MakeFakeLighting(pixelVerts, .03f, .16f, .33f, .10f, 20); initDone=true; } public void onSurfaceChanged(GL10 gl, int nwidth, int nheight) { Width= nwidth; Height = nheight; // avoid division by zero if (Height == 0) Height = 1; // draw on the entire screen gl.glViewport(0, 0, Width, Height); // setup projection matrix gl.glMatrixMode(GL10.GL_PROJECTION); gl.glLoadIdentity(); gl.glOrthof(0, Width, Height, 0, 100, -100); // gl.glOrthof(-nwidth*2, nwidth*2, nheight*2,-nheight*2, 100, -100); // GLU.gluPerspective(gl, 180.0f, (float)nwidth / (float)nheight, // 1000.0f, -1000.0f); gl.glEnable(GL10.GL_BLEND); gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA); System.gc(); if (initDone == false){ SetupStars(); init(gl); } } public void SetupStars(){ backgroundVerts = new float[(int) SumOfStrideI(backgroundData,0,3)*triangleCoords.length]; backgroundColors = new float[(int) SumOfStrideI(backgroundData,0,3)*triangleColors.length]; int iii=0; int vc=0; float ascale=1; for (int i=0;i<backgroundColors.length-1;i=i+1){ if (iii==0){ascale = (float) Math.random();} if (vc==3){ backgroundColors[i]= (float) (triangleColors[iii]*(ascale)); }else if(vc==2){ backgroundColors[i]= (float) (triangleColors[iii]-(Math.random()*.2)); }else{ backgroundColors[i]= (float) (triangleColors[iii]-(Math.random()*.3)); } iii=iii+1;if (iii> triangleColors.length-1){iii=0;} vc=vc+1; if (vc>3){vc=0;} } int ii=0; int i =0; int set =0; while(ii<backgroundVerts.length-1){ float scale = (float) backgroundData[(set*3)+1]; int length= (int) backgroundData[(set*3)]; for (i=0;i<length;i=i+1){ if (set ==0){ AddVertsToArray(ScaleFloats(triangleCoords, scale,scale*.25f), backgroundVerts, (float)(Math.random()*Width),(float) (Math.random()*Height), ii); }else{ AddVertsToArray(ScaleFloats(triangleCoords, scale), backgroundVerts, (float)(Math.random()*Width),(float) (Math.random()*Height), ii);} ii=ii+triangleCoords.length; } set=set+1; } backgroundVertsWrapped = FloatBuffer.wrap(backgroundVerts); backgroundColorsWrapped = FloatBuffer.wrap(backgroundColors); } public void AddVertsToArray(float[] sva,float[]dva,float ox,float oy,int start){ //x for (int i=0;i<sva.length;i=i+3){ if((start+i)<dva.length){dva[start+i]= sva[i]+ox;} } //y for (int i=1;i<sva.length;i=i+3){ if((start+i)<dva.length){dva[start+i]= sva[i]+oy;} } //z for (int i=2;i<sva.length;i=i+3){ if((start+i)<dva.length){dva[start+i]= sva[i];} } } public FloatBuffer MakeFakeLighting(float[] sa,float r, float g,float b,float a,float multby){ float[] da = new float[((sa.length/3)*4)]; int vertex=0; for (int i=0;i<sa.length;i=i+3){ if (sa[i+2]>=1){ da[(vertex*4)+0]= r*multby*sa[i+2]; da[(vertex*4)+1]= g*multby*sa[i+2]; da[(vertex*4)+2]= b*multby*sa[i+2]; da[(vertex*4)+3]= a*multby*sa[i+2]; }else if (sa[i+2]<=-1){ float divisor = (multby*(-sa[i+2])); da[(vertex*4)+0]= r / divisor; da[(vertex*4)+1]= g / divisor; da[(vertex*4)+2]= b / divisor; da[(vertex*4)+3]= a / divisor; }else{ da[(vertex*4)+0]= r; da[(vertex*4)+1]= g; da[(vertex*4)+2]= b; da[(vertex*4)+3]= a; } vertex = vertex+1; } return FloatBuffer.wrap(da); } public float[] ScaleFloats(float[] va,float s){ float[] reta= new float[va.length]; for (int i=0;i<va.length;i=i+1){ reta[i]=va[i]*s; } return reta; } public float[] ScaleFloats(float[] va,float sx,float sy){ float[] reta= new float[va.length]; int cnt = 0; for (int i=0;i<va.length;i=i+1){ if (cnt==0){reta[i]=va[i]*sx;} else if (cnt==1){reta[i]=va[i]*sy;} else if (cnt==2){reta[i]=va[i];} cnt = cnt +1;if (cnt>2){cnt=0;} } return reta; } }

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