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  • What technologies are used for Game development now days?

    - by Monika Michael
    Whenever I ask a question about game development in an online forum I always get suggestions like learning line drawing algorithms, bit level image manipulation and video decompression etc. However looking at games like God of War 3, I find it hard to believe that these games could be developed using such low level techniques. The sheer awesomeness of such games defy any comprehensible(for me) programming methodology. Besides the gaming hardware is really a monster now days. So it stands to reason that the developers would work at a higher level of abstraction. What is the latest development methodology in the gaming industry? How is it that a team of 30-35 developers (of which most is management and marketing fluff) able to make such mind boggling games? If the question seems too general could you explain the architecture of God of War 3? Or how you would go about producing a clone? That I think should be objectively answerable.

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  • How to attach turrets to tiles in a tile based game

    - by Joseph St. Pierre
    I am a flash developer, and I am building a Tower Defense game. The world is being built through tiles, and I have gotten that accomplished easily. I have also gotten level changes and enemy spawning down as well. However, I wish the player to be able to spawn turrets, and have those turrets be on specific tiles, based upon where the player placed it. Here is my code: stop(); colOffset = 50; rowOffset = 50; guns = []; placed = true; dead = 0; spawned = 0; level = 1; interval = 350 / level; amount = level * 20; counter = 0; numCol = 14; numRow = 10; tiles = []; k = 0; create = false; tileName = new Array("road","grass","end", "start"); board = new Array( new Array(1,1,1,1,3,1,1,1,1,1,2,1,1,1), new Array(1,1,1,0,0,1,1,1,1,1,0,1,1,1), new Array(1,1,1,0,1,1,1,1,1,1,0,0,1,1), new Array(1,1,1,0,0,0,1,1,1,1,1,0,1,1), new Array(1,1,1,0,1,0,0,0,1,1,1,0,0,1), new Array(1,1,1,0,1,1,1,0,0,1,1,1,0,1), new Array(1,1,0,0,1,1,1,1,0,1,1,0,0,1), new Array(1,1,0,1,1,1,1,1,0,1,0,0,1,1), new Array(1,1,0,0,0,0,0,0,0,1,0,1,1,1), new Array(1,1,1,1,1,1,1,1,0,0,0,1,1,1) ); buildBoard(); function buildBoard(){ for ( col = 0; col < numCol; col++){ for ( row = 0; row < numRow; row++){ _root.attachMovie("tile", "tile_" + col + "_" + row, _root.getNextHighestDepth()); theTile = eval("tile_" + col + "_" + row); theTile._x = (col * 50); theTile._y = (row * 50); theTile.row = row; theTile.col = col; tileType = board[row][col]; theTile.gotoAndStop(tileName[tileType]); tiles.push(theTile); } } } init(); function init(){ onEnterFrame = function(){ counter += 1; if ( spawned < amount && counter > 50){ min= _root.attachMovie("minion","minion",_root.getNextHighestDepth()); min._x = tile_4_0._x + 25; min._y = tile_4_0._y + 25; min.health = 100; choose = Math.round(Math.random()); if ( choose == 0 ){ min.waypointX = [ tile_4_1._x +25, tile_3_1._x + 25, tile_3_2._x + 25, tile_3_6._x + 25, tile_2_6._x + 25, tile_2_8._x + 25, tile_8_8._x + 25, tile_8_9._x + 25, tile_10_9._x + 25, tile_10_7._x + 25, tile_11_7._x + 25, tile_11_6._x + 25, tile_12_6._x + 25, tile_12_4._x + 25, tile_11_4._x + 25, tile_11_2._x + 25, tile_10_2._x + 25, tile_10_0._x + 25]; min.waypointY = [ tile_4_1._y +25, tile_3_1._y + 25, tile_3_2._y + 25, tile_3_6._y + 25, tile_2_6._y + 25, tile_2_8._y + 25, tile_8_8._y + 25, tile_8_9._y + 25, tile_10_9._y + 25, tile_10_7._y + 25, tile_11_7._y + 25, tile_11_6._y + 25, tile_12_6._y + 25, tile_12_4._y + 25, tile_11_4._y + 25, tile_11_2._y + 25, tile_10_2._y + 25, tile_10_0._y + 25]; } else if ( choose == 1 ){ min.waypointX = [ tile_4_1._x +25, tile_3_1._x + 25, tile_3_2._x + 25, tile_3_3._x + 25, tile_5_3._x + 25, tile_5_4._x + 25, tile_7_4._x + 25, tile_7_5._x + 25, tile_8_5._x + 25, tile_8_8._x + 25, tile_8_9._x + 25, tile_10_9._x + 25, tile_10_7._x + 25, tile_11_7._x + 25, tile_11_6._x + 25, tile_12_6._x + 25, tile_12_4._x + 25, tile_11_4._x + 25, tile_11_2._x + 25, tile_10_2._x + 25, tile_10_0._x + 25 ]; min.waypointY = [ tile_4_1._y +25, tile_3_1._y + 25, tile_3_2._y + 25, tile_3_3._y + 25, tile_5_3._y + 25, tile_5_4._y + 25, tile_7_4._y + 25, tile_7_5._y + 25, tile_8_5._y + 25, tile_8_8._y + 25, tile_8_9._y + 25, tile_10_9._y + 25, tile_10_7._y + 25, tile_11_7._y + 25, tile_11_6._y + 25, tile_12_6._y + 25, tile_12_4._y + 25, tile_11_4._y + 25, tile_11_2._y + 25, tile_10_2._y + 25, tile_10_0._y + 25 ]; } min.i = 0; counter = 0; spawned += 1; min.onEnterFrame = function(){ dx = this.waypointX[this.i] - this._x; dy = this.waypointY[this.i] - this._y; radians = Math.atan2(dy,dx); degrees = radians * 180 / Math.PI; xspeed = Math.cos(radians); yspeed = Math.sin(radians); this._x += xspeed; this._y += yspeed; if( this._x == this.waypointX[this.i] && this._y == this.waypointY[this.i]){ this.i++; } if ( this._x == tile_10_0._x + 25 && this._y == tile_10_0._y + 25){ this.removeMovieClip(); dead += 1; } } } if ( dead >= amount ){ dead = 0; level += 1; amount = level * 20; spawned = 0; } } btnM.onRelease = function(){ create = true; } } game.onEnterFrame = function(){ } It is possible for me however to complete this task, but only once. I am able to make the turret, drag it over to a tile, and have it attach itself to the tile. No problem. The issue is, I cannot do these multiple times. Please Help.

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  • Are there any books dedicated to writing test code? [on hold]

    - by joshin4colours
    There are many programming books dedicated to useful programming and engineering topics, like working with legacy code or particular languages. The best of these books become "standard" or "canonical" references for professional programmers. Are there any books like this (or that could be like this) for writing test code? I don't mean books about Test-Driven Development, nor do I mean books about writing good (clean) code in general. I'm looking for books that discuss test code specifically (unit-level, integration-level, UI-level, design patterns, code structures and organization, etc.)

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  • Farseer: How can I crush Mario? [on hold]

    - by Homer_Simpson
    I want that Mario dies if the box is crushing him. My game has a similar level like this level from New Super Mario Bros. Wii: http://www.youtube.com/watch?v=tYyu6tFAa2M At the beginning of the level, you see some boxes falling to the ground. If a box crushes Mario, he dies. I want to do exactly the same in my game, but I don't know how to do that in Farseer. How can I do that in Farseer 3.3.1? Do you have any suggestions? I don't know how to do the collision detection. I use rectangles for the boxes and ground in Farseer. Mario is a polygon.

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  • Wrong audio volume at boot

    - by skerit
    When I boot my computer and login the volume level is always way too loud. Unfortunately the only way to change it is a physical knob on my speaker. As soon as I can change the volume using my keyboard the volume immediately drops. Say the volume is at 100%, as soon as I turn the dial on my keyboard a little bit it drops to a normal level like 40% How do I get this to work in a clear way, like having it remember the audio level it was on at shutdown? Here's my audio card model: 82801JI (ICH10 Family) HD Audio Controller An Intel card on a Asus motherboard

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  • Enablement 2.0 Get Specialized!

    - by michaela.seika(at)oracle.com
      Check the new OPN Certified Specialist Exam Study Guides – your quick reference to the training options to guide partners pass OPN Specialist Exams! What are the advantages of the Exam Study Guides? Cover the Implementation Specialist Exams that count towards OPN Specialization program. Capture Exam Topics, Exam Objectives and Training Options. Define the Exam Objectives by learner or practitioner level of knowledge: Learner-level: questions require the candidate to recall information to derive the correct answer Practitioner-level: questions require the candidate to derive the correct answer from an application of their knowledge. Map by each Exam Topic the alternative training options that are available at Oracle. Where to find the Exam Study Guides? On Enablement 2.0 > Spotlight On each Knowledge Zone > Implement On each Specialist Implementation Guided Learning Path For More Information Oracle Certification Program Beta Exams OPN Certified Specialist Exams OPN Certified Specialist FAQ Contact Us Please direct any inquiries you may have to Oracle Partner Enablement team at [email protected].

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  • CCUserDefault, iOS/Android and game updates

    - by Luke
    My game uses cocos2d-x and will be published on iOS platform first, later on Android. I save a lot of things with CCUserDefault (scores, which level was completed, number of coins taken, etc...). But now I have a big doubt. What will happen when the game will receive its first update? CCUserDefault uses an XML file stored somewhere in the app storage space. This file is created and retained until one uninstalls the app. I am wondering what happens when the app is updated. Will the old XML file be maintained? Because if not, how should I handle app updates (updates in the sense that 2, 3 or more new level packages will be added, but the informations about the old ones, like scores, which level was finished and which not, number of coins, etc., need absolutely not to be lost)?

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  • What technologies are used for Game development now days?

    - by Monika Michael
    Whenever I ask a question about game development in an online forum I always get suggestions like learning line drawing algorithms, bit level image manipulation and video decompression etc. However looking at games like God of War 3, I find it hard to believe that these games could be developed using such low level techniques. The sheer awesomeness of such games defy any comprehensible(for me) programming methodology. Besides the gaming hardware is really a monster now days. So it stands to reason that the developers would work at a higher level of abstraction. What is the latest development methodology in the gaming industry? How is it that a team of 30-35 developers (of which most is management and marketing fluff) able to make such mind boggling games?

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  • My Oracle Support Accreditation for E-Business Suite

    - by ChristineS-Oracle
    The My Oracle Support Accreditation Series delivers a targeted learning experience that is designed to increase your expertise with My Oracle Support core functions and build skills to help you leverage Oracle product solutions, tools, and knowledge. The accreditation framework for Oracle E-Business Suite is targeted to customers and partners who actively use My Oracle Support and Oracle E-Business Suite. The content is focused on building skills around best practices, recommendations, and tool enablement – taking your expertise with Oracle E-Business Suite to the next level. The Oracle E-Business Suite course covers:•    Staying informed •    Period Close•    Patching•    Certifications •    Upgrade Advisor•    Reporting  Visit the My Oracle Support Accreditation Index and get started with the Level 1 My Oracle Support Accreditation path and the Level 2 Oracle E-Business Suite learning path today.

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  • Victory rewards in digital CCG

    - by Nils Munch
    I am currently polishing a digital CCG where people can play against friend and random opponents in a classical Magic the Gathering-like duel CCG. I plan to award the players with 20 ingame currency units (lets call them gold) for each hour they are playing, 50 for each day they are playing and X for each victory. Now, the X is what I am trying to calculate here, since I would prefer keeping the currency to a certain value, but also with to entice the players to battle. I could go with a solid figure, say 25, for beating up an opponent. But that would result in experienced players only beating up newly started players, making the experience lame for both. I could also make a laddered tier, where you start at level 1, and raise in level as you defeat your opponents, where winning over a player awards you his level x 2 in gold. Which would you prefer if you were playing a game like this. There is no gold-based scoreboard, but the gold is used to purchase new cards along the way.

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  • Is it a good idea to use a formula to balance a game's complexity, in order to keep players in constant flow?

    - by user1107412
    I read a lot about Flow theory and its applications to video games, and I got an idea sticking in my mind. If a number of weight values are applied to different parameters of a certain game level (i.e. the size of the level, the number of enemies, their overal strength, the variance in their behavior, etc), then it should be technically possible to find an overal score mechanism for each level in the game. If a constant ratio of complexity increase were empirically defined, for instance 1,3333, or say, the Golden Ratio, would it be a good idea to arrange the levels in such an order that the increase of overal complexity tends to increase that much? Has somebody tried it?

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  • Use PathModifier of MoveModifier for Tower of Defense Game

    - by Siddharth
    In my game I want to move enemy on the fixed path so that I have establish manual grid structure for that purpose not used tile map. Game contain multiple level and the path will be different for each level and also multiple fixed path exist for each level. So my question is, What I have to use MoveModifier or PathModifier for my game ? Also mention I have to use WayPoint or not. Further detail you all are free to ask. Please help me to decide what to do.

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  • Are the technologies used in an application part of the architecture, or do they represent implementation/detailed design details?

    - by m3th0dman
    When designing and writing documentation for a project an architecture needs to be clearly defined: what are the high-level modules of the system, what are their responsibilities, how do they communicate with each other, what protocols are used etc. But in this list, should the concrete technologies be specified or this is actually an implementation detail and need to be specified at a lower level? For example, consider a distributed application that has two modules which communicate asynchronously via AMQP protocol, mediated by a message broker. The fact that these modules use the Spring AMQP library for sending and receiving messages is a fact that needs to be specified in the architecture or is a lower-level detailed design/implementation detail?

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  • "Time Control" in a 2d Platformer

    - by Woody Zantzinger
    I am making a 2d platformer where the player can press a button, and restart the level, only their previous character will also run the level at the same time, like they are traveling back in time. I know other games have done this before, and the way I have thought of doing it is to make the game character have a set of actions (Idle, Jumping, Walking Left etc.) and then detect changes in those actions and log them into a list along with the game time. So then when I need the character to run the level again on its own, I can just go through the list changing its actions at the right time. Is this the best way to do it? Does anyone have any experience in this? Thanks.

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  • Design: How to model / where to store relational data between classes

    - by Walker
    I'm trying to figure out the best design here, and I can see multiple approaches, but none that seems "right." There are three relevant classes here: Base, TradingPost, and Resource. Each Base has a TradingPost which can offer various Resources depending on the Base's tech level. Where is the right place to store the minimum tech level a base must possess to offer any given resource? A database seems like overkill. Putting it in each subclass of Resource seems wrong--that's not an intrinsic property of the Resource. Do I have a mediating class, and if so, how does it work? It's important that I not be duplicating code; that I have one place where I set the required tech level for a given item. Essentially, where does this data belong? P.S. Feel free to change the title; I struggled to come up with one that fits.

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  • "Time Control" in a 2d Platformer

    - by Woody Zantzinger
    I am making a 2d platformer where the player can press a button, and restart the level, only their previous character will also run the level at the same time, like they are traveling back in time. I know other games have done this before, and the way I have thought of doing it is to make the game character have a set of actions (Idle, Jumping, Walking Left etc.) and then detect changes in those actions and log them into a list along with the game time. So then when I need the character to run the level again on its own, I can just go through the list changing its actions at the right time. Is this the best way to do it? Does anyone have any experience in this? Thanks.

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  • Oracle Service Contracts – Calculate Estimated Tax with Higher Accuracy

    - by LuciaC-Oracle
    On a Service Contract the tax rate and its effectivity can change over the contract duration.  Hence, service organizations need to provide an accurate picture of the estimated tax that the customer might end up paying.  Prior to Release 12.1.3+, the Oracle Service Contracts application calculated the estimated tax based on the line/ sub line start date.  With Release 12.1.3+ (via Patch 16601269:R12.OKS.B) , new functionality provides users with an option to calculate tax at contract billing schedule level, thereby considering the changes in tax rate effectivity at that level.A new profile option 'OKS: Calculate Tax at Schedule' has been introduced which can be used to control whether the existing or new functionality is used.  If the profile is set to 'Yes' the application calculates tax at the billing schedule level for all lines/ sub lines.  For more details on the implementation steps and functionality, please refer to Doc ID 1676700.1: Oracle Service Contracts – How To Calculate Estimated Tax with Higher Accuracy.

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  • Loading Texture2D is extremly slow on XBOX360

    - by AvrDragon
    I have ~100 sprites for each level im my XNA game. On windows it takes ~2 seconds to load them all. Unfortunately on XBOX360 it takes ~30-60 seconds. Am i doing something wrong? Essentially the loading code ist just like this: Texture2D sprite1 = levelContent.Load<Texture2D>("images/level_1/my_sprite_1"); ... Texture2D sprite100 = levelContent.Load<Texture2D>("images/level_1/my_sprite_100"); (i use an own content manager for each level to release all level-specific textures at once) Of course i can reduse the ammount of sprites using a spritesheet, but it's extremly painfull for me now. Do i have a better option? And just curious - why is there such huge difference in image loading time?

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  • Fast lookup for organization hierarchy

    - by Élodie Petit
    I need a way to implement a fast lookup algorithm / system to find users very quickly in a multi-level department and multi-level employee/manager relation organization structure. Departments can have any level of departments and users directly connected to departments. User are connected to departments and other users at the same time. What would be the best approach to implement such a system? There will be approximately 2000 users and 30 departments. Is there a good way to hold all of this information on memory?

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  • My Oracle Support Accreditation for Database and Enterprise Manager

    - by A. G.
    Have you actively used My Oracle Support for 6-9 months? Take your expertise to the next level—become accredited! By completing the accreditation learning series, you can increase your proficiency with My Oracle Support’s core functions and build skills to help you leverage Oracle solutions, tools, and knowledge that enable productivity. Accreditation learning paths are available for Oracle Database and Enterprise Manager, which focus on product-specific best practices, recommendations, and tool enablement—up leveling your capabilities with these Oracle products. Course topics include:   Oracle Database Staying informed  Install Patching Upgrade Performance Security Scalability Enterprise Manager Staying informed  Supportability Certification Patching Upgrade Performance Diagnostic Tools Troubleshooting Visit the My Oracle Support Accreditation Index and get started with the Level 1 My Oracle Support Accreditation path and product-specific Level 2 learning paths for Oracle Database and Enterprise Manager.

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  • How to do pre-loading

    - by Dave
    I have a question that is confusing me with making a game. For my game launch i pre load everything for the main menu then i loop the game to display it. But lets argue player wants to launch a new game or a specific level, then you preload the relevant sounds/graphics for that level right? How ever, the player must already be running the game loop if they are at the main menu, so you can't load in the game loop or you will load every frame...but im pretty sure most big games don't preload every level when you first run the game from desktop because it would take a long time on some of these games.... How is it done :S

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  • Shifting from XNA/C# to C++?

    - by Fat_Scout
    For a while now, I've been working with XNA for game design and development (although only for personal use ATM.) Overall, I'm a major fan of XNA itself, and it's overall "feel." However, due to the fact that: XNA seems to have a lack of support (no Metro support, no updates since 2010, etc.) I plan to try and get a job in the game development industry, and due to C++'s dominance, being more familiar with it would be very useful XNA only supports Windows (non-Metro) and Xbox 360, while I am interested in Mac and (to a lesser extent) Linux support. I've been trying to shift over to C++ as my main language. However, I do not want to focus on learning raw DirectX/C++ at this time, so I've been looking for a higher level C++ API (something about the same level as XNA, although something a bit more low-level would be fine) with a feel similar to XNA. So, for someone switching from C#/XNA to C++, what would my best choice(s) be for API's similar to XNA, although unmanaged and running on C++?

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  • Programming vs Planning

    - by MattW
    Recently I have been tasked with more High level planning assignments due to the lead developer of my team leaving. I hate long term planning. My brain just doesn't naturally seem wired for it and I am not interested enough in it to spend the time to learn it (it is hard enough to keep up with the programming side of the picture). Can I still be a good programmer without being a high level planer too? Are you expected to be good at planning out the entire product and picking a date, as part of being a senior programmer. Is it possible to be a good programmer and not a high level planner?

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  • What is the best taxonomy from Google's perspective?

    - by ZakGottlieb
    I was wondering what the best way is to structure a new website in Google's eyes. Currently, it contains two top-level categories (X & Y), and clicking a term under either one will result in the URL: www.nameofsite.com/X/X type term, or /Y/Y type term Technically, it is correct to group all "X type terms" under X and "Y type terms" under Y, but we could probably be more granular and break all articles into 5-6 top-level categories by breaking Y up into more specific categories. Given that the current URL structure will eventually result in 1000's of "X type terms" and "Y type terms" under just two top-level categories, would it be more advisable to have several of these, as suggested? Thank you in advance.

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  • C# Performance Pitfall – Interop Scenarios Change the Rules

    - by Reed
    C# and .NET, overall, really do have fantastic performance in my opinion.  That being said, the performance characteristics dramatically differ from native programming, and take some relearning if you’re used to doing performance optimization in most other languages, especially C, C++, and similar.  However, there are times when revisiting tricks learned in native code play a critical role in performance optimization in C#. I recently ran across a nasty scenario that illustrated to me how dangerous following any fixed rules for optimization can be… The rules in C# when optimizing code are very different than C or C++.  Often, they’re exactly backwards.  For example, in C and C++, lifting a variable out of loops in order to avoid memory allocations often can have huge advantages.  If some function within a call graph is allocating memory dynamically, and that gets called in a loop, it can dramatically slow down a routine. This can be a tricky bottleneck to track down, even with a profiler.  Looking at the memory allocation graph is usually the key for spotting this routine, as it’s often “hidden” deep in call graph.  For example, while optimizing some of my scientific routines, I ran into a situation where I had a loop similar to: for (i=0; i<numberToProcess; ++i) { // Do some work ProcessElement(element[i]); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This loop was at a fairly high level in the call graph, and often could take many hours to complete, depending on the input data.  As such, any performance optimization we could achieve would be greatly appreciated by our users. After a fair bit of profiling, I noticed that a couple of function calls down the call graph (inside of ProcessElement), there was some code that effectively was doing: // Allocate some data required DataStructure* data = new DataStructure(num); // Call into a subroutine that passed around and manipulated this data highly CallSubroutine(data); // Read and use some values from here double values = data->Foo; // Cleanup delete data; // ... return bar; Normally, if “DataStructure” was a simple data type, I could just allocate it on the stack.  However, it’s constructor, internally, allocated it’s own memory using new, so this wouldn’t eliminate the problem.  In this case, however, I could change the call signatures to allow the pointer to the data structure to be passed into ProcessElement and through the call graph, allowing the inner routine to reuse the same “data” memory instead of allocating.  At the highest level, my code effectively changed to something like: DataStructure* data = new DataStructure(numberToProcess); for (i=0; i<numberToProcess; ++i) { // Do some work ProcessElement(element[i], data); } delete data; Granted, this dramatically reduced the maintainability of the code, so it wasn’t something I wanted to do unless there was a significant benefit.  In this case, after profiling the new version, I found that it increased the overall performance dramatically – my main test case went from 35 minutes runtime down to 21 minutes.  This was such a significant improvement, I felt it was worth the reduction in maintainability. In C and C++, it’s generally a good idea (for performance) to: Reduce the number of memory allocations as much as possible, Use fewer, larger memory allocations instead of many smaller ones, and Allocate as high up the call stack as possible, and reuse memory I’ve seen many people try to make similar optimizations in C# code.  For good or bad, this is typically not a good idea.  The garbage collector in .NET completely changes the rules here. In C#, reallocating memory in a loop is not always a bad idea.  In this scenario, for example, I may have been much better off leaving the original code alone.  The reason for this is the garbage collector.  The GC in .NET is incredibly effective, and leaving the allocation deep inside the call stack has some huge advantages.  First and foremost, it tends to make the code more maintainable – passing around object references tends to couple the methods together more than necessary, and overall increase the complexity of the code.  This is something that should be avoided unless there is a significant reason.  Second, (unlike C and C++) memory allocation of a single object in C# is normally cheap and fast.  Finally, and most critically, there is a large advantage to having short lived objects.  If you lift a variable out of the loop and reuse the memory, its much more likely that object will get promoted to Gen1 (or worse, Gen2).  This can cause expensive compaction operations to be required, and also lead to (at least temporary) memory fragmentation as well as more costly collections later. As such, I’ve found that it’s often (though not always) faster to leave memory allocations where you’d naturally place them – deep inside of the call graph, inside of the loops.  This causes the objects to stay very short lived, which in turn increases the efficiency of the garbage collector, and can dramatically improve the overall performance of the routine as a whole. In C#, I tend to: Keep variable declarations in the tightest scope possible Declare and allocate objects at usage While this tends to cause some of the same goals (reducing unnecessary allocations, etc), the goal here is a bit different – it’s about keeping the objects rooted for as little time as possible in order to (attempt) to keep them completely in Gen0, or worst case, Gen1.  It also has the huge advantage of keeping the code very maintainable – objects are used and “released” as soon as possible, which keeps the code very clean.  It does, however, often have the side effect of causing more allocations to occur, but keeping the objects rooted for a much shorter time. Now – nowhere here am I suggesting that these rules are hard, fast rules that are always true.  That being said, my time spent optimizing over the years encourages me to naturally write code that follows the above guidelines, then profile and adjust as necessary.  In my current project, however, I ran across one of those nasty little pitfalls that’s something to keep in mind – interop changes the rules. In this case, I was dealing with an API that, internally, used some COM objects.  In this case, these COM objects were leading to native allocations (most likely C++) occurring in a loop deep in my call graph.  Even though I was writing nice, clean managed code, the normal managed code rules for performance no longer apply.  After profiling to find the bottleneck in my code, I realized that my inner loop, a innocuous looking block of C# code, was effectively causing a set of native memory allocations in every iteration.  This required going back to a “native programming” mindset for optimization.  Lifting these variables and reusing them took a 1:10 routine down to 0:20 – again, a very worthwhile improvement. Overall, the lessons here are: Always profile if you suspect a performance problem – don’t assume any rule is correct, or any code is efficient just because it looks like it should be Remember to check memory allocations when profiling, not just CPU cycles Interop scenarios often cause managed code to act very differently than “normal” managed code. Native code can be hidden very cleverly inside of managed wrappers

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