<html> <head> <meta content="text/html; charset=utf-8" http-equiv="Content-Type"> </head> <body bgcolor="#FFFFFF" text="#000000"> Hi Jose, thanks for replying, I've seen your name inside many files in mesa ;) I have tried mesa master (previously I was using 17.0.1) but it still crashes for the same null pointer. Do you have a link to that patch you've mentioned for kotor? I have used apitrace and took traces of both the nvidia driver (which runs kotor) and mesa (up until the crash). Here's a link to them: <a href="https://drive.google.com/file/d/0B6qj91UlSYlYa3dIM0FtaHNULW8/view?usp=sharing">https://drive.google.com/file/d/0B6qj91UlSYlYa3dIM0FtaHNULW8/view?usp=sharing</a> I tried reading them with the dump function but it's way above my comprehension. I know that some applications use wglGetProcAddress to check if an extension if available, but I've seen KOTOR check for the WGL_ARB_render_texture, and when it's present it enables frame buffer effects and soft shadows, which use wglMakeContextCurrentARB (not wglBindTexImageARB, I was wrong in my previous mail), which for some reason is a null pointer. <div class="moz-cite-prefix">Il 2017-03-13 14:39, Jose Fonseca ha scritto: </div> <blockquote cite="mid:deb551d4-fa06-9534-c848-11dc0dd528fb@vmware.com" type="cite">On 13/03/17 11:09, Emil Velikov wrote: <blockquote type="cite">On 11 March 2017 at 11:51, Federico Dossena <a class="moz-txt-link-rfc2396E" href="mailto:dossenus91@gmail.com"><dossenus91@gmail.com></a> wrote: <blockquote type="cite">In the last week I've been trying to bring an "old" game back to life, Star Wars Knights of the old republic (KOTOR, for short). It's from 2003 and uses OpenGL 1.4. I have used Mesa, libtxc_dxtn and some trickery to decompress the textures to boost performance, and right now I have it up and running smoothly with Gallium on LLVMPipe, compiled on Windows. (I can upload a copy if someone is interested). This took me about 2 days of compiling and figuring out stuff. Here's where the weirdness begins: Turning on framebuffer effects or soft shadows make the game crash right after the menu. Using a disassembler and debugger and what little knowledge I have of reverse engineering, I managed to track down the issue to a function which uses wglGetProcAddress to get the addresses of several OpenGL functions. Some of these calls return a null pointer (even if there is a valid context and it is current), and when the game tries to call them, it crashes. The first one that makes it crash is a pointer to wglBindTexImageARB, but there are a few others. NOPing the offending instructions did not work, and returning a nop function just makes the game display artifacts. </blockquote> Strange - afaict mesa (st/wgl) exposes both wglBindTexImageARB and the WGL_ARB_render_texture extension. You can break on DrvGetProcAddress and trace where/how we end up with NULL function pointer. -Emil _______________________________________________ mesa-dev mailing list <a class="moz-txt-link-abbreviated" href="mailto:mesa-dev@lists.freedesktop.org">mesa-dev@lists.freedesktop.org</a> <a class="moz-txt-link-freetext" href="https://lists.freedesktop.org/mailman/listinfo/mesa-dev">https://lists.freedesktop.org/mailman/listinfo/mesa-dev</a> </blockquote> Federico, You should be using latest master for this. There have been recent changes/fixes to our WGL implementation. Last fall Brian Paul fixed an issue with WGL extension seen on KOTOR. I'm not sure the the issue has been crossported to Mesa master yet, and it might be unrelated. Generally speaking, wglGetProcAddress returning NULL by itself is not a problem. Many games wrongly rely on wglGetProcAddress NULL results to detect whether an GL/WGL extension is present (which goes against the spec). Other libraries try to bindly get every possible entrypoint through wglGetProcAddress, then check which ones to use based on supported extensions (which is actually fine by the spec.) For the record, getting an apitrace is usually useful to debug this sort of issues. One can use apitrace straigh from windows or with WINE -- <a class="moz-txt-link-freetext" href="https://github.com/apitrace/apitrace/wiki/WINE">https://github.com/apitrace/apitrace/wiki/WINE</a> Jose </blockquote> </body> </html>