Search Results

Search found 142 results on 6 pages for 'offsets'.

Page 4/6 | < Previous Page | 1 2 3 4 5 6  | Next Page >

  • What's the best way to apply a drop shadow?

    - by jckeyes
    What is the best method for applying drop shadows? I'm working on a site right now where we have a good deal of them, however, I've been fighting to find the best method to do it. The site is pretty animation heavy so shadows need to work well with this. I tried a jQuery shadow pulgin. The shadows looked good and were easy to use but were slow and didn't work well with any animations (required lots of redrawing, very joggy). I also tried creating my own jQuery extension that wraps my element in a couple gray divs and then offsets them a little bit to give a shadow effect. This worked well. It's quick and responsive to the animation. However, it makes DOM manipulation/traversal cumbersome since everything is wrapped in these shadow divs. I know there has to be a better way but this isn't exactly my forte. Thoughts?

    Read the article

  • Stopping pirates

    - by Pirate for Profit
    Okay, what do I do to stop pirates? Obviously a callhome to internet service. We are considering making some major aspects be dependent on a web service of some sort. Memory offsets and cracking. If I like rand randomly to allocate empty memory on the heap, would this throw off the crackers? I hacked some memory shit for EverQuest back in the dizzay but don't really know much about this. Registry on windows, etc., I know theres ways to identify the computer. That's easily spoofed with hex editor, but if I jumble up the strings in the program would that help? I need to know that + real ideas. I want the serials of their sound cards. Any other ideas?

    Read the article

  • What does setting the GL color before doing a texture mapping operation do?

    - by quixoto
    I am looking at some sample code in a book that creates a jittered antialiasing effect by repeatedly rendering a scene (at different offsets) onto a offscreen texture, then using that texture to repeatedly draw a quad in the main view with some blend stuff set up. To accumulate the color "correctly", the code is setting the color like so: glColor4f(f, f, f, 1); where f is 1.0/number_of_samples, and then binding the offscreen texture and rendering it. Since textures come with their own color and alpha data, what is the effect (mathematically and intuitively) that setting the overall "color" in advance achieves? Thanks.

    Read the article

  • In Bloomberg API how do you specify to get FX forwards as a spread rather than absolute values?

    - by Nick Fortescue
    How do you explicitly request fx forwards as outrights using the bloomberg API? In the Bloomberg terminal you can choose whether to get FX Forwards as absolute rates (outrights) or as offsets from Spots (Points) by doing XDF, hitting 7, then the option is about half way down. 0 means outrights, and 1 means offfsets. With most defaults you can explicitly set them in the API, so your code gives the same result whichever computer you run on. How do you set this one in a V3 API query?

    Read the article

  • Using virtual fields in Doctrine_Query

    - by James Maroney
    Is there a way to insert logic based on virtual fields into a Doctrine_Query? I have defined a virtual field in my model, "getStatus()" which I would ultimately like to utilize in a Where clause in my Doctrine_Query. ... ->AndWhere('x.status = ?',$status); "status", however, is not a column in the table it is instead computed by business logic in the model. Filtering the Collection after executing the query works in some situations, but not when a Doctrine_Pager is thrown in the mix, as it computes it's offsets and such before you have access to the Collection. Am I best off ditching Doctrine_Pager and rebuilding that functionality after modifying the Doctrine_Collection?

    Read the article

  • What are the ways to create draw data structures for latex?

    - by alicephacker
    I tried tikz/pgf a bit but have not had much luck creating a nice diagram to visualize bitfields or byte fields of packed data structures (i.e. in memory). Essentially I want a set of rectangles representing ranges of bits with labels inside, and offsets along the top. There should be multiple rows for each word of the data structure. This is similar to most of the diagrams in most processor manuals labeling opcode encoding etc. Has anyone else tried to do this using latex or is there a package for this?

    Read the article

  • How to vertically align an inline image with inline text following it?

    - by amn
    Is there any way to vertically align an image element generated by a "content" property as part of a ":before" selector, next to adjacent inline text? In other words, I have <a href="..." class="facebook">Share on Facebook</a> As I don't want to pollute my markup with unnecessary IMG elements that only have to do with style, I resort to adding a small icon to the left of the link, via CSS (except that it does not align properly, hence the question): a.facebook:before { content: url(/style/facebook-logo.png); } I tried adding a "vertical-align: middle" (one of the most notoriously difficult aligning concepts to grasp in CSS, in my opinion, is that very property) but it has no effect. The logo aligns with text baseline, and I don't want to hardcode pixel offsets, because frankly text size differs from browser to browser, etc. Is there any solution for this? Thanks.

    Read the article

  • iPhone OpenGL Template is cheating?

    - by carrots
    XCode's OpenGL template seems to be cheating to solve this "stretched" viewport problem I've been trying to understand for the last 3 hours. In the iphone "OpenGL ES Application" template, the colorful square that bounces up and down on the screen is not really a square at all! ES1Renderer.m (the ES2 file as well) static const GLfloat squareVertices[] = { -0.5f, -0.33f, 0.5f, -0.33f, -0.5f, 0.33f, 0.5f, 0.33f, }; But it comes out looking square on the device/simulator due to the stretching/squashing effect of a non-square viewport. I tried to fix it by fiddling with glFrustumf() but that doesn't seem to change the aspect ratio. I was able to get things looking good (not-stretched) when I fed glViewport() with a 1:1 widht:height.. But this doesn't seem like the answer because it offsets the viewport placement. What's the right way to correct for this stretching and why doesn't XCode do it that way?

    Read the article

  • PHP and C# communication with Encrypt/Decrypt

    - by SilentWarrior
    Hello, I have been searching and cant find a consistent solution to my problem : I want to encrypt something in C# and decrypt it in PHP but also be able to encrypt in PHP and decrypt in C#, using the same key on both ends. All the solutions I found dont seem to work both ways, most of them only work on one language and then fail on the other, either by decrypting wrong or by blowing up the offsets. I would like to use TripleDES but it isnt a requirement, just want something relatively strong for plain text communication (will either use JSON or just plain key-value pairs for complex stuff). Thanks in advance PS: http://pastie.org/643106 this is what I have been testing with.

    Read the article

  • Add 64 bit offset to a pointer

    - by Novox
    In F#, there's the NativePtr module, but it seems to only support 32 bit offsets for its’ add/get/set functions, just like System.IntPtr does. Is there a way to add a 64 bit offset to a native pointer (nativeptr<'a) in F#? Of course I could convert all addresses to 64 bit integers, do normal integer operations and then convert the result again to nativeptr<'a, but this would cost additional add and imul instructions. I really want the AGUs to perform the address calculations. For instance, using unsafe in C# you could do something like void* ptr = Marshal.AllocHGlobal(...).ToPointer(); int64 offset = ...; T* newAddr = (T*)ptr + offset; // T has to be an unmanaged type Well actually you can't, because there is no "unmanaged" constraint for type parameters, but at least you can do general pointer arithmetic in a non-generic way. In F# we finally got the unmanaged constraint; but how do I do the pointer arithmetic?

    Read the article

  • SQLite issues, escaping certain characters...

    - by CODe
    I'm working on my first database application. It is a WinForms application written in C# using a SQLite database. I've come across some problems, when a apostrophe is used, my SQLite query fails. Here is the structure of my queries. string SQL = "UPDATE SUBCONTRACTOR SET JobSite = NULL WHERE JobSite = '" + jobSite + "'"; For instance, if an apostrophe is used in the jobSite var, it offsets the other apostrophes in the command, and fails. So my questions are: 1. How do I escape characters like the apostrophe and semicolon in the above query example? 2. What characters do I need to escape? I know I should escape the apostrophe, what else is dangerous? Thanks for your help!

    Read the article

  • Ancillary Objects: Separate Debug ELF Files For Solaris

    - by Ali Bahrami
    We introduced a new object ELF object type in Solaris 11 Update 1 called the Ancillary Object. This posting describes them, using material originally written during their development, the PSARC arc case, and the Solaris Linker and Libraries Manual. ELF objects contain allocable sections, which are mapped into memory at runtime, and non-allocable sections, which are present in the file for use by debuggers and observability tools, but which are not mapped or used at runtime. Typically, all of these sections exist within a single object file. Ancillary objects allow them to instead go into a separate file. There are different reasons given for wanting such a feature. One can debate whether the added complexity is worth the benefit, and in most cases it is not. However, one important case stands out — customers with very large 32-bit objects who are not ready or able to make the transition to 64-bits. We have customers who build extremely large 32-bit objects. Historically, the debug sections in these objects have used the stabs format, which is limited, but relatively compact. In recent years, the industry has transitioned to the powerful but verbose DWARF standard. In some cases, the size of these debug sections is large enough to push the total object file size past the fundamental 4GB limit for 32-bit ELF object files. The best, and ultimately only, solution to overly large objects is to transition to 64-bits. However, consider environments where: Hundreds of users may be executing the code on large shared systems. (32-bits use less memory and bus bandwidth, and on sparc runs just as fast as 64-bit code otherwise). Complex finely tuned code, where the original authors may no longer be available. Critical production code, that was expensive to qualify and bring online, and which is otherwise serving its intended purpose without issue. Users in these risk adverse and/or high scale categories have good reasons to push 32-bits objects to the limit before moving on. Ancillary objects offer these users a longer runway. Design The design of ancillary objects is intended to be simple, both to help human understanding when examining elfdump output, and to lower the bar for debuggers such as dbx to support them. The primary and ancillary objects have the same set of section headers, with the same names, in the same order (i.e. each section has the same index in both files). A single added section of type SHT_SUNW_ANCILLARY is added to both objects, containing information that allows a debugger to identify and validate both files relative to each other. Given one of these files, the ancillary section allows you to identify the other. Allocable sections go in the primary object, and non-allocable ones go into the ancillary object. A small set of non-allocable objects, notably the symbol table, are copied into both objects. As noted above, most sections are only written to one of the two objects, but both objects have the same section header array. The section header in the file that does not contain the section data is tagged with the SHF_SUNW_ABSENT section header flag to indicate its placeholder status. Compiler writers and others who produce objects can set the SUNW_SHF_PRIMARY section header flag to mark non-allocable sections that should go to the primary object rather than the ancillary. If you don't request an ancillary object, the Solaris ELF format is unchanged. Users who don't use ancillary objects do not pay for the feature. This is important, because they exist to serve a small subset of our users, and must not complicate the common case. If you do request an ancillary object, the runtime behavior of the primary object will be the same as that of a normal object. There is no added runtime cost. The primary and ancillary object together represent a logical single object. This is facilitated by the use of a single set of section headers. One can easily imagine a tool that can merge a primary and ancillary object into a single file, or the reverse. (Note that although this is an interesting intellectual exercise, we don't actually supply such a tool because there's little practical benefit above and beyond using ld to create the files). Among the benefits of this approach are: There is no need for per-file symbol tables to reflect the contents of each file. The same symbol table that would be produced for a standard object can be used. The section contents are identical in either case — there is no need to alter data to accommodate multiple files. It is very easy for a debugger to adapt to these new files, and the processing involved can be encapsulated in input/output routines. Most of the existing debugger implementation applies without modification. The limit of a 4GB 32-bit output object is now raised to 4GB of code, and 4GB of debug data. There is also the future possibility (not currently supported) to support multiple ancillary objects, each of which could contain up to 4GB of additional debug data. It must be noted however that the 32-bit DWARF debug format is itself inherently 32-bit limited, as it uses 32-bit offsets between debug sections, so the ability to employ multiple ancillary object files may not turn out to be useful. Using Ancillary Objects (From the Solaris Linker and Libraries Guide) By default, objects contain both allocable and non-allocable sections. Allocable sections are the sections that contain executable code and the data needed by that code at runtime. Non-allocable sections contain supplemental information that is not required to execute an object at runtime. These sections support the operation of debuggers and other observability tools. The non-allocable sections in an object are not loaded into memory at runtime by the operating system, and so, they have no impact on memory use or other aspects of runtime performance no matter their size. For convenience, both allocable and non-allocable sections are normally maintained in the same file. However, there are situations in which it can be useful to separate these sections. To reduce the size of objects in order to improve the speed at which they can be copied across wide area networks. To support fine grained debugging of highly optimized code requires considerable debug data. In modern systems, the debugging data can easily be larger than the code it describes. The size of a 32-bit object is limited to 4 Gbytes. In very large 32-bit objects, the debug data can cause this limit to be exceeded and prevent the creation of the object. To limit the exposure of internal implementation details. Traditionally, objects have been stripped of non-allocable sections in order to address these issues. Stripping is effective, but destroys data that might be needed later. The Solaris link-editor can instead write non-allocable sections to an ancillary object. This feature is enabled with the -z ancillary command line option. $ ld ... -z ancillary[=outfile] ...By default, the ancillary file is given the same name as the primary output object, with a .anc file extension. However, a different name can be provided by providing an outfile value to the -z ancillary option. When -z ancillary is specified, the link-editor performs the following actions. All allocable sections are written to the primary object. In addition, all non-allocable sections containing one or more input sections that have the SHF_SUNW_PRIMARY section header flag set are written to the primary object. All remaining non-allocable sections are written to the ancillary object. The following non-allocable sections are written to both the primary object and ancillary object. .shstrtab The section name string table. .symtab The full non-dynamic symbol table. .symtab_shndx The symbol table extended index section associated with .symtab. .strtab The non-dynamic string table associated with .symtab. .SUNW_ancillary Contains the information required to identify the primary and ancillary objects, and to identify the object being examined. The primary object and all ancillary objects contain the same array of sections headers. Each section has the same section index in every file. Although the primary and ancillary objects all define the same section headers, the data for most sections will be written to a single file as described above. If the data for a section is not present in a given file, the SHF_SUNW_ABSENT section header flag is set, and the sh_size field is 0. This organization makes it possible to acquire a full list of section headers, a complete symbol table, and a complete list of the primary and ancillary objects from either of the primary or ancillary objects. The following example illustrates the underlying implementation of ancillary objects. An ancillary object is created by adding the -z ancillary command line option to an otherwise normal compilation. The file utility shows that the result is an executable named a.out, and an associated ancillary object named a.out.anc. $ cat hello.c #include <stdio.h> int main(int argc, char **argv) { (void) printf("hello, world\n"); return (0); } $ cc -g -zancillary hello.c $ file a.out a.out.anc a.out: ELF 32-bit LSB executable 80386 Version 1 [FPU], dynamically linked, not stripped, ancillary object a.out.anc a.out.anc: ELF 32-bit LSB ancillary 80386 Version 1, primary object a.out $ ./a.out hello worldThe resulting primary object is an ordinary executable that can be executed in the usual manner. It is no different at runtime than an executable built without the use of ancillary objects, and then stripped of non-allocable content using the strip or mcs commands. As previously described, the primary object and ancillary objects contain the same section headers. To see how this works, it is helpful to use the elfdump utility to display these section headers and compare them. The following table shows the section header information for a selection of headers from the previous link-edit example. Index Section Name Type Primary Flags Ancillary Flags Primary Size Ancillary Size 13 .text PROGBITS ALLOC EXECINSTR ALLOC EXECINSTR SUNW_ABSENT 0x131 0 20 .data PROGBITS WRITE ALLOC WRITE ALLOC SUNW_ABSENT 0x4c 0 21 .symtab SYMTAB 0 0 0x450 0x450 22 .strtab STRTAB STRINGS STRINGS 0x1ad 0x1ad 24 .debug_info PROGBITS SUNW_ABSENT 0 0 0x1a7 28 .shstrtab STRTAB STRINGS STRINGS 0x118 0x118 29 .SUNW_ancillary SUNW_ancillary 0 0 0x30 0x30 The data for most sections is only present in one of the two files, and absent from the other file. The SHF_SUNW_ABSENT section header flag is set when the data is absent. The data for allocable sections needed at runtime are found in the primary object. The data for non-allocable sections used for debugging but not needed at runtime are placed in the ancillary file. A small set of non-allocable sections are fully present in both files. These are the .SUNW_ancillary section used to relate the primary and ancillary objects together, the section name string table .shstrtab, as well as the symbol table.symtab, and its associated string table .strtab. It is possible to strip the symbol table from the primary object. A debugger that encounters an object without a symbol table can use the .SUNW_ancillary section to locate the ancillary object, and access the symbol contained within. The primary object, and all associated ancillary objects, contain a .SUNW_ancillary section that allows all the objects to be identified and related together. $ elfdump -T SUNW_ancillary a.out a.out.anc a.out: Ancillary Section: .SUNW_ancillary index tag value [0] ANC_SUNW_CHECKSUM 0x8724 [1] ANC_SUNW_MEMBER 0x1 a.out [2] ANC_SUNW_CHECKSUM 0x8724 [3] ANC_SUNW_MEMBER 0x1a3 a.out.anc [4] ANC_SUNW_CHECKSUM 0xfbe2 [5] ANC_SUNW_NULL 0 a.out.anc: Ancillary Section: .SUNW_ancillary index tag value [0] ANC_SUNW_CHECKSUM 0xfbe2 [1] ANC_SUNW_MEMBER 0x1 a.out [2] ANC_SUNW_CHECKSUM 0x8724 [3] ANC_SUNW_MEMBER 0x1a3 a.out.anc [4] ANC_SUNW_CHECKSUM 0xfbe2 [5] ANC_SUNW_NULL 0 The ancillary sections for both objects contain the same number of elements, and are identical except for the first element. Each object, starting with the primary object, is introduced with a MEMBER element that gives the file name, followed by a CHECKSUM that identifies the object. In this example, the primary object is a.out, and has a checksum of 0x8724. The ancillary object is a.out.anc, and has a checksum of 0xfbe2. The first element in a .SUNW_ancillary section, preceding the MEMBER element for the primary object, is always a CHECKSUM element, containing the checksum for the file being examined. The presence of a .SUNW_ancillary section in an object indicates that the object has associated ancillary objects. The names of the primary and all associated ancillary objects can be obtained from the ancillary section from any one of the files. It is possible to determine which file is being examined from the larger set of files by comparing the first checksum value to the checksum of each member that follows. Debugger Access and Use of Ancillary Objects Debuggers and other observability tools must merge the information found in the primary and ancillary object files in order to build a complete view of the object. This is equivalent to processing the information from a single file. This merging is simplified by the primary object and ancillary objects containing the same section headers, and a single symbol table. The following steps can be used by a debugger to assemble the information contained in these files. Starting with the primary object, or any of the ancillary objects, locate the .SUNW_ancillary section. The presence of this section identifies the object as part of an ancillary group, contains information that can be used to obtain a complete list of the files and determine which of those files is the one currently being examined. Create a section header array in memory, using the section header array from the object being examined as an initial template. Open and read each file identified by the .SUNW_ancillary section in turn. For each file, fill in the in-memory section header array with the information for each section that does not have the SHF_SUNW_ABSENT flag set. The result will be a complete in-memory copy of the section headers with pointers to the data for all sections. Once this information has been acquired, the debugger can proceed as it would in the single file case, to access and control the running program. Note - The ELF definition of ancillary objects provides for a single primary object, and an arbitrary number of ancillary objects. At this time, the Oracle Solaris link-editor only produces a single ancillary object containing all non-allocable sections. This may change in the future. Debuggers and other observability tools should be written to handle the general case of multiple ancillary objects. ELF Implementation Details (From the Solaris Linker and Libraries Guide) To implement ancillary objects, it was necessary to extend the ELF format to add a new object type (ET_SUNW_ANCILLARY), a new section type (SHT_SUNW_ANCILLARY), and 2 new section header flags (SHF_SUNW_ABSENT, SHF_SUNW_PRIMARY). In this section, I will detail these changes, in the form of diffs to the Solaris Linker and Libraries manual. Part IV ELF Application Binary Interface Chapter 13: Object File Format Object File Format Edit Note: This existing section at the beginning of the chapter describes the ELF header. There's a table of object file types, which now includes the new ET_SUNW_ANCILLARY type. e_type Identifies the object file type, as listed in the following table. NameValueMeaning ET_NONE0No file type ET_REL1Relocatable file ET_EXEC2Executable file ET_DYN3Shared object file ET_CORE4Core file ET_LOSUNW0xfefeStart operating system specific range ET_SUNW_ANCILLARY0xfefeAncillary object file ET_HISUNW0xfefdEnd operating system specific range ET_LOPROC0xff00Start processor-specific range ET_HIPROC0xffffEnd processor-specific range Sections Edit Note: This overview section defines the section header structure, and provides a high level description of known sections. It was updated to define the new SHF_SUNW_ABSENT and SHF_SUNW_PRIMARY flags and the new SHT_SUNW_ANCILLARY section. ... sh_type Categorizes the section's contents and semantics. Section types and their descriptions are listed in Table 13-5. sh_flags Sections support 1-bit flags that describe miscellaneous attributes. Flag definitions are listed in Table 13-8. ... Table 13-5 ELF Section Types, sh_type NameValue . . . SHT_LOSUNW0x6fffffee SHT_SUNW_ancillary0x6fffffee . . . ... SHT_LOSUNW - SHT_HISUNW Values in this inclusive range are reserved for Oracle Solaris OS semantics. SHT_SUNW_ANCILLARY Present when a given object is part of a group of ancillary objects. Contains information required to identify all the files that make up the group. See Ancillary Section. ... Table 13-8 ELF Section Attribute Flags NameValue . . . SHF_MASKOS0x0ff00000 SHF_SUNW_NODISCARD0x00100000 SHF_SUNW_ABSENT0x00200000 SHF_SUNW_PRIMARY0x00400000 SHF_MASKPROC0xf0000000 . . . ... SHF_SUNW_ABSENT Indicates that the data for this section is not present in this file. When ancillary objects are created, the primary object and any ancillary objects, will all have the same section header array, to facilitate merging them to form a complete view of the object, and to allow them to use the same symbol tables. Each file contains a subset of the section data. The data for allocable sections is written to the primary object while the data for non-allocable sections is written to an ancillary file. The SHF_SUNW_ABSENT flag is used to indicate that the data for the section is not present in the object being examined. When the SHF_SUNW_ABSENT flag is set, the sh_size field of the section header must be 0. An application encountering an SHF_SUNW_ABSENT section can choose to ignore the section, or to search for the section data within one of the related ancillary files. SHF_SUNW_PRIMARY The default behavior when ancillary objects are created is to write all allocable sections to the primary object and all non-allocable sections to the ancillary objects. The SHF_SUNW_PRIMARY flag overrides this behavior. Any output section containing one more input section with the SHF_SUNW_PRIMARY flag set is written to the primary object without regard for its allocable status. ... Two members in the section header, sh_link, and sh_info, hold special information, depending on section type. Table 13-9 ELF sh_link and sh_info Interpretation sh_typesh_linksh_info . . . SHT_SUNW_ANCILLARY The section header index of the associated string table. 0 . . . Special Sections Edit Note: This section describes the sections used in Solaris ELF objects, using the types defined in the previous description of section types. It was updated to define the new .SUNW_ancillary (SHT_SUNW_ANCILLARY) section. Various sections hold program and control information. Sections in the following table are used by the system and have the indicated types and attributes. Table 13-10 ELF Special Sections NameTypeAttribute . . . .SUNW_ancillarySHT_SUNW_ancillaryNone . . . ... .SUNW_ancillary Present when a given object is part of a group of ancillary objects. Contains information required to identify all the files that make up the group. See Ancillary Section for details. ... Ancillary Section Edit Note: This new section provides the format reference describing the layout of a .SUNW_ancillary section and the meaning of the various tags. Note that these sections use the same tag/value concept used for dynamic and capabilities sections, and will be familiar to anyone used to working with ELF. In addition to the primary output object, the Solaris link-editor can produce one or more ancillary objects. Ancillary objects contain non-allocable sections that would normally be written to the primary object. When ancillary objects are produced, the primary object and all of the associated ancillary objects contain a SHT_SUNW_ancillary section, containing information that identifies these related objects. Given any one object from such a group, the ancillary section provides the information needed to identify and interpret the others. This section contains an array of the following structures. See sys/elf.h. typedef struct { Elf32_Word a_tag; union { Elf32_Word a_val; Elf32_Addr a_ptr; } a_un; } Elf32_Ancillary; typedef struct { Elf64_Xword a_tag; union { Elf64_Xword a_val; Elf64_Addr a_ptr; } a_un; } Elf64_Ancillary; For each object with this type, a_tag controls the interpretation of a_un. a_val These objects represent integer values with various interpretations. a_ptr These objects represent file offsets or addresses. The following ancillary tags exist. Table 13-NEW1 ELF Ancillary Array Tags NameValuea_un ANC_SUNW_NULL0Ignored ANC_SUNW_CHECKSUM1a_val ANC_SUNW_MEMBER2a_ptr ANC_SUNW_NULL Marks the end of the ancillary section. ANC_SUNW_CHECKSUM Provides the checksum for a file in the c_val element. When ANC_SUNW_CHECKSUM precedes the first instance of ANC_SUNW_MEMBER, it provides the checksum for the object from which the ancillary section is being read. When it follows an ANC_SUNW_MEMBER tag, it provides the checksum for that member. ANC_SUNW_MEMBER Specifies an object name. The a_ptr element contains the string table offset of a null-terminated string, that provides the file name. An ancillary section must always contain an ANC_SUNW_CHECKSUM before the first instance of ANC_SUNW_MEMBER, identifying the current object. Following that, there should be an ANC_SUNW_MEMBER for each object that makes up the complete set of objects. Each ANC_SUNW_MEMBER should be followed by an ANC_SUNW_CHECKSUM for that object. A typical ancillary section will therefore be structured as: TagMeaning ANC_SUNW_CHECKSUMChecksum of this object ANC_SUNW_MEMBERName of object #1 ANC_SUNW_CHECKSUMChecksum for object #1 . . . ANC_SUNW_MEMBERName of object N ANC_SUNW_CHECKSUMChecksum for object N ANC_SUNW_NULL An object can therefore identify itself by comparing the initial ANC_SUNW_CHECKSUM to each of the ones that follow, until it finds a match. Related Other Work The GNU developers have also encountered the need/desire to support separate debug information files, and use the solution detailed at http://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html. At the current time, the separate debug file is constructed by building the standard object first, and then copying the debug data out of it in a separate post processing step, Hence, it is limited to a total of 4GB of code and debug data, just as a single object file would be. They are aware of this, and I have seen online comments indicating that they may add direct support for generating these separate files to their link-editor. It is worth noting that the GNU objcopy utility is available on Solaris, and that the Studio dbx debugger is able to use these GNU style separate debug files even on Solaris. Although this is interesting in terms giving Linux users a familiar environment on Solaris, the 4GB limit means it is not an answer to the problem of very large 32-bit objects. We have also encountered issues with objcopy not understanding Solaris-specific ELF sections, when using this approach. The GNU community also has a current effort to adapt their DWARF debug sections in order to move them to separate files before passing the relocatable objects to the linker. The details of Project Fission can be found at http://gcc.gnu.org/wiki/DebugFission. The goal of this project appears to be to reduce the amount of data seen by the link-editor. The primary effort revolves around moving DWARF data to separate .dwo files so that the link-editor never encounters them. The details of modifying the DWARF data to be usable in this form are involved — please see the above URL for details.

    Read the article

  • 13.04 Logitech bluetooth speaker adapter pairing but no mixer output

    - by user1455622
    I had to change [General] Enable = Socket in /etc/bluetooth/audio.conf to get it to pair. But now that they are I don't get an output in pavucontrol. D: [pulseaudio] bluetooth-util.c: Registering /MediaEndpoint/HFPAG on adapter /org/bluez/3855/hci0. D: [pulseaudio] bluetooth-util.c: Registering /MediaEndpoint/HFPHS on adapter /org/bluez/3855/hci0. D: [pulseaudio] bluetooth-util.c: Registering /MediaEndpoint/A2DPSource on adapter /org/bluez/3855/hci0. D: [pulseaudio] bluetooth-util.c: Registering /MediaEndpoint/A2DPSink on adapter /org/bluez/3855/hci0. E: [pulseaudio] bluetooth-util.c: org.bluez.Media.RegisterEndpoint() failed: org.bluez.Error.AlreadyExists: Already Exists E: [pulseaudio] bluetooth-util.c: org.bluez.Media.RegisterEndpoint() failed: org.bluez.Error.AlreadyExists: Already Exists E: [pulseaudio] bluetooth-util.c: org.bluez.Media.RegisterEndpoint() failed: org.bluez.Error.AlreadyExists: Already Exists E: [pulseaudio] bluetooth-util.c: org.bluez.Media.RegisterEndpoint() failed: org.bluez.Error.AlreadyExists: Already Exists D: [pulseaudio] bluetooth-util.c: dbus: property 'State' changed to value 'disconnected' D: [pulseaudio] bluetooth-util.c: dbus: property 'State' changed to value 'disconnected' D: [pulseaudio] bluetooth-util.c: dbus: property 'State' changed to value 'disconnected' D: [pulseaudio] bluetooth-util.c: dbus: property 'State' changed to value 'disconnected' D: [pulseaudio] bluetooth-util.c: dbus: property 'State' changed to value 'connected' D: [pulseaudio] bluetooth-util.c: dbus: property 'State' changed to value 'connected' D: [pulseaudio] bluetooth-util.c: Unknown Bluetooth minor device class 0 D: [pulseaudio] module-card-restore.c: Not restoring profile for card bluez_card.C8_84_47_15_B7_34, because already set. I: [pulseaudio] module-card-restore.c: Restoring port latency offsets for card bluez_card.C8_84_47_15_B7_34. I: [pulseaudio] card.c: Created 2 "bluez_card.C8_84_47_15_B7_34" W: [pulseaudio] module-bluetooth-device.c: Profile has no transport D: [pulseaudio] core-subscribe.c: Dropped redundant event due to change event. I: [pulseaudio] card.c: Changed profile of card 2 "bluez_card.C8_84_47_15_B7_34" to off I: [pulseaudio] module.c: Loaded "module-bluetooth-device" (index: #22; argument: "address=C8:84:47:15:B7:34 profile=a2dp"). I: [alsa-source] alsa-source.c: Scheduling delay of 10,06ms, you might want to investigate this to improve latency... I: [alsa-source] ratelimit.c: 5 events suppressed I: [alsa-source] alsa-source.c: Overrun! I: [alsa-source] alsa-source.c: Increasing minimal latency to 2,00 ms D: [alsa-source] alsa-source.c: latency set to 20,00ms D: [alsa-source] alsa-source.c: hwbuf_unused=62008 D: [alsa-source] alsa-source.c: setting avail_min=442 What can I do to get it working? Regards,

    Read the article

  • Multi Pass Blend

    - by Kirk Patrick
    I am seeking the simplest working example of a two pass HLSL pixel shader. It can do anything really, but the main idea is to perform "ping ponging" to take the output of the first pass and then send it for the second pass. In my example I want to draw to the R channel and then draw to the G channel and produce a simple Venn Diagram in the shader, but need to detect overlap. I can currently detect one or the other but not overlap. There are a red and green circle overlapping, and I want to put a dynamic texture map in the overlap region. I can currently put it in either or. Below is how it looks in the shader. -------------------------------- Texture2D shaderTexture; SamplerState SampleType; ////////////// // TYPEDEFS // ////////////// struct PixelInputType { float4 position : SV_POSITION; float2 tex0 : TEXCOORD0; float2 tex1 : TEXCOORD1; float4 color : COLOR; }; //////////////////////////////////////////////////////////////////////////////// // Pixel Shader //////////////////////////////////////////////////////////////////////////////// float4 main(PixelInputType input) : SV_TARGET { float4 textureColor0; float4 textureColor1; // Sample the pixel color from the texture using the sampler at this texture coordinate location. textureColor0 = shaderTexture.Sample(SampleType, input.tex0); textureColor1 = shaderTexture.Sample(SampleType, input.tex1); if (input.color[0]==1.0f && input.color[1]==1.0f) // Requires multi-pass textureColor0 = textureColor1; return textureColor0; } Here is the calling code (that needs to be modified) m_d3dContext->IASetVertexBuffers(0, 2, vbs, strides, offsets); m_d3dContext->IASetIndexBuffer(m_indexBuffer.Get(), DXGI_FORMAT_R32_UINT,0); m_d3dContext->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST); m_d3dContext->IASetInputLayout(m_inputLayout.Get()); m_d3dContext->VSSetShader(m_vertexShader.Get(), nullptr, 0); m_d3dContext->VSSetConstantBuffers(0, 1, m_constantBuffer.GetAddressOf()); m_d3dContext->PSSetShader(m_pixelShader.Get(), nullptr, 0); m_d3dContext->PSSetShaderResources(0, 1, m_SRV.GetAddressOf()); m_d3dContext->PSSetSamplers(0, 1, m_QuadsTexSamplerState.GetAddressOf());

    Read the article

  • Rendering Texture Quad to Screen or FBO (OpenGL ES)

    - by Usman.3D
    I need to render the texture on the iOS device's screen or a render-to-texture frame buffer object. But it does not show any texture. It's all black. (I am loading texture with image myself for testing purpose) //Load texture data UIImage *image=[UIImage imageNamed:@"textureImage.png"]; GLuint width = FRAME_WIDTH; GLuint height = FRAME_HEIGHT; //Create context void *imageData = malloc(height * width * 4); CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); CGContextRef context = CGBitmapContextCreate(imageData, width, height, 8, 4 * width, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big); CGColorSpaceRelease(colorSpace); //Prepare image CGContextClearRect(context, CGRectMake(0, 0, width, height)); CGContextDrawImage(context, CGRectMake(0, 0, width, height), image.CGImage); glGenTextures(1, &texture); glBindTexture(GL_TEXTURE_2D, texture); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, imageData); glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); Simple Texture Quad drawing code mentioned here //Bind Texture, Bind render-to-texture FBO and then draw the quad const float quadPositions[] = { 1.0, 1.0, 0.0, -1.0, 1.0, 0.0, -1.0, -1.0, 0.0, -1.0, -1.0, 0.0, 1.0, -1.0, 0.0, 1.0, 1.0, 0.0 }; const float quadTexcoords[] = { 1.0, 1.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 1.0, 1.0 }; // stop using VBO glBindBuffer(GL_ARRAY_BUFFER, 0); // setup buffer offsets glVertexAttribPointer(ATTRIB_VERTEX, 3, GL_FLOAT, GL_FALSE, 3*sizeof(float), quadPositions); glVertexAttribPointer(ATTRIB_TEXCOORD0, 2, GL_FLOAT, GL_FALSE, 2*sizeof(float), quadTexcoords); // ensure the proper arrays are enabled glEnableVertexAttribArray(ATTRIB_VERTEX); glEnableVertexAttribArray(ATTRIB_TEXCOORD0); //Bind Texture and render-to-texture FBO. glBindTexture(GL_TEXTURE_2D, GLid); //Actually wanted to render it to render-to-texture FBO, but now testing directly on default FBO. //glBindFramebuffer(GL_FRAMEBUFFER, textureFBO[pixelBuffernum]); // draw glDrawArrays(GL_TRIANGLES, 0, 2*3); What am I doing wrong in this code? P.S. I'm not familiar with shaders yet, so it is difficult for me to make use of them right now.

    Read the article

  • Java @Contented annotation to help reduce false sharing

    - by Dave
    See this posting by Aleksey Shipilev for details -- @Contended is something we've wanted for a long time. The JVM provides automatic layout and placement of fields. Usually it'll (a) sort fields by descending size to improve footprint, and (b) pack reference fields so the garbage collector can process a contiguous run of reference fields when tracing. @Contended gives the program a way to provide more explicit guidance with respect to concurrency and false sharing. Using this facility we can sequester hot frequently written shared fields away from other mostly read-only or cold fields. The simple rule is that read-sharing is cheap, and write-sharing is very expensive. We can also pack fields together that tend to be written together by the same thread at about the same time. More generally, we're trying to influence relative field placement to minimize coherency misses. Fields that are accessed closely together in time should be placed proximally in space to promote cache locality. That is, temporal locality should condition spatial locality. Fields accessed together in time should be nearby in space. That having been said, we have to be careful to avoid false sharing and excessive invalidation from coherence traffic. As such, we try to cluster or otherwise sequester fields that tend to written at approximately the same time by the same thread onto the same cache line. Note that there's a tension at play: if we try too hard to minimize single-threaded capacity misses then we can end up with excessive coherency misses running in a parallel environment. Theres no single optimal layout for both single-thread and multithreaded environments. And the ideal layout problem itself is NP-hard. Ideally, a JVM would employ hardware monitoring facilities to detect sharing behavior and change the layout on the fly. That's a bit difficult as we don't yet have the right plumbing to provide efficient and expedient information to the JVM. Hint: we need to disintermediate the OS and hypervisor. Another challenge is that raw field offsets are used in the unsafe facility, so we'd need to address that issue, possibly with an extra level of indirection. Finally, I'd like to be able to pack final fields together as well, as those are known to be read-only.

    Read the article

  • How do I improve my incremental-backup performance?

    - by Alistair Bell
    I'm currently using the traditional rsync+cp -al method to create incremental/snapshot backups of our server tree. The backups are going onto a pair of eight-disk towers connected to the backup machine (a Sandy Bridge machine with 16 GB of RAM, running CentOS 5.5) via four eSATA connections (four disks per connection). Each disk is a regular 2 TB disk, so we have 32 TB of disk space connected to the backup machine. We're backing up about 20 TB of data on the servers with this. The problem is that each daily backup is taking more than 24 hours, and the real time-killer isn't the actual rsync, but the time it takes to perform a cp -al of the tree locally on the backup machine. It's taking more than 12 hours just to make the shadow copy of the tree, and as far as I can tell the performance backlog is at the disk (top shows the cp using a lot of RAM but not a lot of CPU and mostly in uninterruptible-sleep state) We have the server data split into four major volumes (and a few minor ones), and each of these backups runs in parallel (with some offsets in the cron to try to get some disks' cp done first). There are two volumes on the backup drive, both striped LVM volumes of 16 TB each. So obviously I need to improve the performance because it's unusable as it stands. The first question is: when CentOS 6 comes out, with support for btrfs, will making snapshots of subvolumes with btrfs substantially increase this performance? The second is: is there a way, with ext3 or something else supported in CentOS 5 or 6, to 'encourage' it to put the directories/inodes in one part of a volume (which could happen to be the part that's on an SSD, via LVM) and the files in another? That would presumably solve the problem, but I don't know of ways to hint ext3 like that.

    Read the article

  • What are the advantages and disadvantages of the various virtual machine image formats?

    - by Matt
    Xen and Virtualbox etc both support a range of different virtual machine image formats. These are: vmdk, vdi, qcow & qcow2, hdd & vhd. Without any bias toward a particular product, I'm wanting to know what are the advantages and disadvantages of the various formats both from a features perspective, robustness and speed? One piece of info I discovered in a forum post was this: "The major difference is that VDI uses relatively large blocks (1MB) when growing an image, and thus has less overhead for block pointers etc. but isn't ultimately space efficient in the sense that if a single byte is non-zero in such a 1MB block the entire space is used. VMDK in contrast uses 64K blocks, and thus has more management overhead and generally a bit less disk space consumption What offsets this is that VDI is more efficient when it comes to snapshots." You might be thinking, I want to know this because I want to know which format to choose? Not exactly, I'm developing some software which utilises these formats and want to support one or more of them. Simplicity, large disks and ease of development are my main drivers.

    Read the article

  • MySQL-Cluster or Multi-Master for production? Performance issues?

    - by Phillip Oldham
    We are expanding our network of webservers on EC2 to a number of different regions and currently use master/slave replication. We've found that over the past couple of months our slave has stopped replicating a number of times which required us to clear the db and initialise the replication again. As we're now looking to have servers in 3 different regions we're a little concerned about these MySQL replication errors. We believe they're due to auto_increment values, so we're considering a number of approaches to quell these errors and stabilise replication: Multi-Master replication; 3 masters (one in each region), with the relevant auto_increment offsets, regularly backing up to S3. Or, MySQL-Cluster; 3 nodes (one in each region) with a separate management node which will also aggregate logs and statistics. After investigating it seems they both have down-sides (replication errors for the former, performance issues for the latter). We believe the cluster approach would allow us to manage and add new nodes more easily than the Multi-Master route, and would reduce/eliminate the replication issues we're currently seeing. But performance is a priority. Are the performance issues of MySQL-Cluster as bad as people say?

    Read the article

  • ntpd on Fedora Core 6 with high negative time reset values

    - by Mark White
    The basic problem is we have a FC6 server instance running on a virtual machine, and the system time seems to have been slowly varying until it is now causing a problem. The server runs 24/7 and has been up for 155 days. It has been changed to show GMT, and reports the time as (example) 00:15:15 GMT whereas the actual time is 00:00:00 GMT. This is an offset of 915 seconds. selinux has been changed to 'setenforce 0' for testing and I am running as root. I stop the ntpd service and change the time in System|Administration|Date & Time. The time still shows the same with 'date' in bash. There are no error logs. I change the date with 'date --set' in bash. The response confirms the changed date. I run 'date' and the incorrect date is shown. There are no error logs. I start the ntpd service and /var/log/messages shows success with 'time reset -915.720139s'. The date remains unchanged. ntpq -p shows three three time servers all have offsets of around -915 seconds. I stop ntpd service and try 'ntpd -gqx' and get the same result as above - success, but a large negative time reset. I've tried varying combinations of the above, and a few more settings in System|Administration|Date & Time - no change. I just need to reset the system time to GMT. No offset. But I can't wait for ntpd to slew the time over the next few weeks. Any advice is welcome, cheers! Surely this shouldn't be this difficult... Mark...

    Read the article

  • Create a class that inherets DrawableGameComponent in XNA as a CLASS with custom functions

    - by user3675013
    using Microsoft.Xna.Framework.Graphics; using Microsoft.Xna.Framework.Media; using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Content; namespace TileEngine { class Renderer : DrawableGameComponent { public Renderer(Game game) : base(game) { } SpriteBatch spriteBatch ; protected override void LoadContent() { base.LoadContent(); } public override void Draw(GameTime gameTime) { base.Draw(gameTime); } public override void Update(GameTime gameTime) { base.Update(gameTime); } public override void Initialize() { base.Initialize(); } public RenderTarget2D new_texture(int width, int height) { Texture2D TEX = new Texture2D(GraphicsDevice, width, height); //create the texture to render to RenderTarget2D Mine = new RenderTarget2D(GraphicsDevice, width, height); GraphicsDevice.SetRenderTarget(Mine); //set the render device to the reference provided //maybe base.draw can be used with spritebatch. Idk. We'll see if the order of operation //works out. Wish I could call base.draw here. return Mine; //I'm hoping that this returns the same instance and not a copy. } public void draw_texture(int width, int height, RenderTarget2D Mine) { GraphicsDevice.SetRenderTarget(null); //Set the renderer to render to the backbuffer again Rectangle drawrect = new Rectangle(0, 0, width, height); //Set the rendering size to what we want spriteBatch.Begin(); //This uses spritebatch to draw the texture directly to the screen spriteBatch.Draw(Mine, drawrect, Color.White); //This uses the color white spriteBatch.End(); //ends the spritebatch //Call base.draw after this since it doesn't seem to recognize inside the function //maybe base.draw can be used with spritebatch. Idk. We'll see if the order of operation //works out. Wish I could call base.draw here. } } } I solved a previous issue where I wasn't allowed to access GraphicsDevice outside the main Default 'main' class Ie "Game" or "Game1" etc. Now I have a new issue. FYi no one told me that it would be possible to use GraphicsDevice References to cause it to not be null by using the drawable class. (hopefully after this last bug is solved it doesn't still return null) Anyways at present the problem is that I can't seem to get it to initialize as an instance in my main program. Ie Renderer tileClipping; and I'm unable to use it such as it is to be noted i haven't even gotten to testing these two steps below but before it compiled but when those functions of this class were called it complained that it can't render to a null device. Which meant that the device wasn't being initialized. I had no idea why. It took me hours to google this. I finally figured out the words I needed.. which were "do my rendering in XNA in a seperate class" now I haven't used the addcomponent function because I don't want it to only run these functions automatically and I want to be able to call the custom ones. In a nutshell what I want is: *access to rendering targets and graphics device OUTSIDE default class *passing of Rendertarget2D (which contain textures and textures should automatically be passed with a rendering target? ) *the device should be passed to this function as well OR the device should be passed to this function as a byproduct of passing the rendertarget (which is automatically associated with the render device it was given originally) *I'm assuming I'm dealing with abstracted pointers here so when I pass a class object or instance, I should be recieving the SAME object , I referenced, and not a copy that has only the lifespan of the function running. *the purpose for all these options: I want to initialize new 2d textures on the fly to customize tileclipping and even the X , y Offsets of where a WHOLE texture will be rendered, and the X and Y offsets of where tiles will be rendered ON that surface. This is why. And I'll be doing region based lighting effects per tile or even per 8X8 pixel spaces.. we'll see I'll also be doing sprite rotations on the whole texture then copying it again to a circular masked texture, and then doing a second copy for only solid tiles for masked rotated collisions on sprites. I'll be checking the masked pixels for my collision, and using raycasting possibly to check for collisions on those areas. The sprite will stay in the center, when this rotation happens. Here is a detailed diagram: http://i.stack.imgur.com/INf9K.gif I'll be using texture2D for steps 4-6 I suppose for steps 1 as well. Now ontop of that, the clipping size (IE the sqaure rendered) will be able to be shrunk or increased, on a per frame basis Therefore I can't use the same static size for my main texture2d and I can't use just the backbuffer Or we get the annoying flicker. Also I will have multiple instances of the renderer class so that I can freely pass textures around as if they are playing cards (in a sense) layering them ontop of eachother, cropping them how i want and such. and then using spritebatch to simply draw them at the locations I want. Hopefully this makes sense, and yes I will be planning on using alpha blending but only after all tiles have been drawn.. The masked collision is important and Yes I am avoiding using math on the tile rendering and instead resorting to image manipulation in video memory which is WHY I need this to work the way I'm intending it to work and not in the default way that XNA seems to handle graphics. Thanks to anyone willing to help. I hate the code form offered, because then I have to rely on static presence of an update function. What if I want to kill that update function or that object, but have it in memory, but just have it temporarily inactive? I'm making the assumption here the update function of one of these gamecomponents is automatic ? Anyways this is as detailed as I can make this post hopefully someone can help me solve the issue. Instead of tell me "derrr don't do it this wayyy" which is what a few people told me (but they don't understand the actual goal I have in mind) I'm trying to create basically a library where I can copy images freely no matter the size, i just have to specify the size in the function then as long as a reference to that object exists it should be kept alive? right? :/ anyways.. Anything else? I Don't know. I understand object oriented coding but I don't understand this XNA It's beggining to feel impossible to do anything custom in it without putting ALL my rendering code into the draw function of the main class tileClipping.new_texture(GraphicsDevice, width, height) tileClipping.Draw_texture(...)

    Read the article

  • Initializing and drawing a mesh using OpenTK

    - by Boreal
    I'm implementing a "Mesh" class to use in my OpenTK game. You pass in a vertex array and an index array, and then you can call Mesh.Draw() to draw it using a shader. I've heard VBO's and VAO's are the way to go for this approach, but nowhere have I found a guide that shows how to get Data Video Memory Shader. Can someone give me a quick rundown of how this works? EDIT: So far, I have this: struct Vertex { public Vector3 position; public Vector3 normal; public Vector3 color; public static int memSize = 9 * sizeof(float); public static byte[] memOffset = { 0, 3 * sizeof(float), 6 * sizeof(float) }; } class Mesh { private uint vbo; private uint ibo; // stores the numbers of vertices and indices private int numVertices; private int numIndices; public Mesh(int numVertices, Vertex[] vertices, int numIndices, ushort[] indices) { // set numbers this.numVertices = numVertices; this.numIndices = numIndices; // generate buffers GL.GenBuffers(1, out vbo); GL.GenBuffers(1, out ibo); GL.BindBuffer(BufferTarget.ArrayBuffer, vbo); GL.BindBuffer(BufferTarget.ElementArrayBuffer, ibo); // send data to the buffers GL.BufferData(BufferTarget.ArrayBuffer, new IntPtr(Vertex.memSize * numVertices), vertices, BufferUsageHint.StaticDraw); GL.BufferData(BufferTarget.ElementArrayBuffer, new IntPtr(sizeof(ushort) * numIndices), indices, BufferUsageHint.StaticDraw); } public void Render() { // bind buffers GL.BindBuffer(BufferTarget.ArrayBuffer, vbo); GL.BindBuffer(BufferTarget.ElementArrayBuffer, ibo); // define offsets GL.VertexPointer(3, VertexPointerType.Float, Vertex.memSize, new IntPtr(Vertex.memOffset[0])); GL.NormalPointer(NormalPointerType.Float, Vertex.memSize, new IntPtr(Vertex.memOffset[1])); GL.ColorPointer(3, ColorPointerType.Float, Vertex.memSize, new IntPtr(Vertex.memOffset[2])); // draw GL.DrawElements(BeginMode.Triangles, numIndices, DrawElementsType.UnsignedInt, (IntPtr)0); } } class Application : GameWindow { Mesh triangle; protected override void OnLoad(EventArgs e) { base.OnLoad(e); GL.ClearColor(0.1f, 0.2f, 0.5f, 0.0f); GL.Enable(EnableCap.DepthTest); GL.Enable(EnableCap.VertexArray); GL.Enable(EnableCap.NormalArray); GL.Enable(EnableCap.ColorArray); Vertex v0 = new Vertex(); v0.position = new Vector3(-1.0f, -1.0f, 4.0f); v0.normal = new Vector3(0.0f, 0.0f, -1.0f); v0.color = new Vector3(1.0f, 1.0f, 0.0f); Vertex v1 = new Vertex(); v1.position = new Vector3(1.0f, -1.0f, 4.0f); v1.normal = new Vector3(0.0f, 0.0f, -1.0f); v1.color = new Vector3(1.0f, 0.0f, 0.0f); Vertex v2 = new Vertex(); v2.position = new Vector3(0.0f, 1.0f, 4.0f); v2.normal = new Vector3(0.0f, 0.0f, -1.0f); v2.color = new Vector3(0.2f, 0.9f, 1.0f); Vertex[] va = { v0, v1, v2 }; ushort[] ia = { 0, 1, 2 }; triangle = new Mesh(3, va, 3, ia); } protected override void OnRenderFrame(FrameEventArgs e) { base.OnRenderFrame(e); GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit); Matrix4 modelview = Matrix4.LookAt(Vector3.Zero, Vector3.UnitZ, Vector3.UnitY); GL.MatrixMode(MatrixMode.Modelview); GL.LoadMatrix(ref modelview); triangle.Render(); SwapBuffers(); } } It doesn't draw anything.

    Read the article

  • How to use caching to increase render performance?

    - by Christian Ivicevic
    First of all I am going to cover the basic design of my 2d tile-based engine written with SDL in C++, then I will point out what I am up to and where I need some hints. Concept of my engine My engine uses the concept of GameScreens which are stored on a stack in the main game class. The main methods of a screen are usually LoadContent, Render, Update and InitMultithreading. (I use the last one because I am using v8 as a JavaScript bridge to the engine. The main game loop then renders the top screen on the stack (if there is one; otherwise, it exits the game) - actually it calls the render methods, but stores all items to be rendered in a list. After gathering all this information the methods like SDL_BlitSurface are called by my GameUIRenderer which draws the enqueued content and then draws some overlay. The code looks like this: while(Game is running) { Handle input if(Screens on stack == 0) exit Update timer etc. Clear the screen Peek the screen on the stack and collect information on what to render Actually render the enqueue screen stuff and some overlay etc. Flip the screen } The GameUIRenderer uses as hinted a std::vector<std::shared_ptr<ImageToRender>> to hold all necessary information described by this class: class ImageToRender { private: SDL_Surface* image; int x, y, w, h, xOffset, yOffset; }; This bunch of attributes is usually needed if I have a texture atlas with all tiles in one SDL_Surface and then the engine should crop one specific area and draw this to the screen. The GameUIRenderer::Render() method then just iterates over all elements and renders them something like this: std::for_each( this->m_vImageVector.begin(), this->m_vImageVector.end(), [this](std::shared_ptr<ImageToRender> pCurrentImage) { SDL_Rect rc = { pCurrentImage->x, pCurrentImage->y, 0, 0 }; // For the sake of simplicity ignore offsets... SDL_Rect srcRect = { 0, 0, pCurrentImage->w, pCurrentImage->h }; SDL_BlitSurface(pCurrentImage->pImage, &srcRect, g_pFramework->GetScreen(), &rc); } ); this->m_vImageVector.clear(); Current ideas which need to be reviewed The specified approach works really good and IMHO it is really has a good structure, however the performance could be definitely increased. I would like to know what do you suggest, how to implement efficient caching of surfaces etc so that there is no need to redraw the same scene over and over again? The map itself would be almost static, only when the player moves, we would need to move the map. Furthermore animated entities would either require updates of the whole map or updates of only the specific areas the entities are currently moving in. My first approaches were to include a flag IsTainted which should be used by the GameUIRenderer to decide whether to redraw everything or use cached version (or to not render anything so that we do not have to Clear the screen and let the last frame persist). However this seems to be quite messy if I have to manually handle in my Render method of the screen class if something has changed or not.

    Read the article

  • Problems with 3D Array for Voxel Data

    - by Sean M.
    I'm trying to implement a voxel engine in C++ using OpenGL, and I've been working on the rendering of the world. In order to render, I have a 3D array of uint16's that hold that id of the block at the point. I also have a 3D array of uint8's that I am using to store the visibility data for that point, where each bit represents if a face is visible. I have it so the blocks render and all of the proper faces are hidden if needed, but all of the blocks are offset by a power of 2 from where they are stored in the array. So the block at [0][0][0] is rendered at (0, 0, 0), and the block at 11 is rendered at (1, 1, 1), but the block at [2][2][2] is rendered at (4, 4, 4) and the block at [3][3][3] is rendered at (8, 8, 8), and so on and so forth. This is the result of drawing the above situation: I'm still a little new to the more advanced concepts of C++, like triple pointers, which I'm using for the 3D array, so I think the error is somewhere in there. This is the code for creating the arrays: uint16*** _blockData; //Contains a 3D array of uint16s that are the ids of the blocks in the region uint8*** _visibilityData; //Contains a 3D array of bytes that hold the visibility data for the faces //Allocate memory for the world data _blockData = new uint16**[REGION_DIM]; for (int i = 0; i < REGION_DIM; i++) { _blockData[i] = new uint16*[REGION_DIM]; for (int j = 0; j < REGION_DIM; j++) _blockData[i][j] = new uint16[REGION_DIM]; } //Allocate memory for the visibility _visibilityData = new uint8**[REGION_DIM]; for (int i = 0; i < REGION_DIM; i++) { _visibilityData[i] = new uint8*[REGION_DIM]; for (int j = 0; j < REGION_DIM; j++) _visibilityData[i][j] = new uint8[REGION_DIM]; } Here is the code used to create the block mesh for the region: //Check if the positive x face is visible, this happens for every face //Block::VERT_X_POS is just an array of non-transformed cube verts for one face //These checks are in a triple loop, which goes over every place in the array if (_visibilityData[x][y][z] & 0x01 > 0) { _vertexData->AddData(&(translateVertices(Block::VERT_X_POS, x, y, z)[0]), sizeof(Block::VERT_X_POS)); } //This is a seperate method, not in the loop glm::vec3* translateVertices(const glm::vec3 data[], uint16 x, uint16 y, uint16 z) { glm::vec3* copy = new glm::vec3[6]; memcpy(&copy, &data, sizeof(data)); for(int i = 0; i < 6; i++) copy[i] += glm::vec3(x, -y, z); //Make +y go down instead return copy; } I cannot see where the blocks may be getting offset by more than they should be, and certainly not why the offsets are a power of 2. Any help is greatly appreciated. Thanks.

    Read the article

  • Getting 2D Platformer entity collision Response Correct (side-to-side + jumping/landing on heads)

    - by jbrennan
    I've been working on a 2D (tile based) 2D platformer for iOS and I've got basic entity collision detection working, but there's just something not right about it and I can't quite figure out how to solve it. There are 2 forms of collision between player entities as I can tell, either the two players (human controlled) are hitting each other side-to-side (i. e. pushing against one another), or one player has jumped on the head of the other player (naturally, if I wanted to expand this to player vs enemy, the effects would be different, but the types of collisions would be identical, just the reaction should be a little different). In my code I believe I've got the side-to-side code working: If two entities press against one another, then they are both moved back on either side of the intersection rectangle so that they are just pushing on each other. I also have the "landed on the other player's head" part working. The real problem is, if the two players are currently pushing up against each other, and one player jumps, then at one point as they're jumping, the height-difference threshold that counts as a "land on head" is passed and then it registers as a jump. As a life-long player of 2D Mario Bros style games, this feels incorrect to me, but I can't quite figure out how to solve it. My code: (it's really Objective-C but I've put it in pseudo C-style code just to be simpler for non ObjC readers) void checkCollisions() { // For each entity in the scene, compare it with all other entities (but not with one it's already compared against) for (int i = 0; i < _allGameObjects.count(); i++) { // GameObject is an Entity GEGameObject *firstGameObject = _allGameObjects.objectAtIndex(i); // Don't check against yourself or any previous entity for (int j = i+1; j < _allGameObjects.count(); j++) { GEGameObject *secondGameObject = _allGameObjects.objectAtIndex(j); // Get the collision bounds for both entities, then see if they intersect // CGRect is a C-struct with an origin Point (x, y) and a Size (w, h) CGRect firstRect = firstGameObject.collisionBounds(); CGRect secondRect = secondGameObject.collisionBounds(); // Collision of any sort if (CGRectIntersectsRect(firstRect, secondRect)) { //////////////////////////////// // // // Check for jumping first (???) // // //////////////////////////////// if (firstRect.origin.y > (secondRect.origin.y + (secondRect.size.height * 0.7))) { // the top entity could be pretty far down/in to the bottom entity.... firstGameObject.didLandOnEntity(secondGameObject); } else if (secondRect.origin.y > (firstRect.origin.y + (firstRect.size.height * 0.7))) { // second entity was actually on top.... secondGameObject.didLandOnEntity.(firstGameObject); } else if (firstRect.origin.x > secondRect.origin.x && firstRect.origin.x < (secondRect.origin.x + secondRect.size.width)) { // Hit from the RIGHT CGRect intersection = CGRectIntersection(firstRect, secondRect); // The NUDGE just offsets either object back to the left or right // After the nudging, they are exactly pressing against each other with no intersection firstGameObject.nudgeToRightOfIntersection(intersection); secondGameObject.nudgeToLeftOfIntersection(intersection); } else if ((firstRect.origin.x + firstRect.size.width) > secondRect.origin.x) { // hit from the LEFT CGRect intersection = CGRectIntersection(firstRect, secondRect); secondGameObject.nudgeToRightOfIntersection(intersection); firstGameObject.nudgeToLeftOfIntersection(intersection); } } } } } I think my collision detection code is pretty close, but obviously I'm doing something a little wrong. I really think it's to do with the way my jumps are checked (I wanted to make sure that a jump could happen from an angle (instead of if the falling player had been at a right angle to the player below). Can someone please help me here? I haven't been able to find many resources on how to do this properly (and thinking like a game developer is new for me). Thanks in advance!

    Read the article

< Previous Page | 1 2 3 4 5 6  | Next Page >