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OpenGL [SDL] Super slow framerate on Windows 7, GLEW shaders unavailable

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Hello!

I've been working on a project off and on in SDL for a number of months now, and I've had an issue from the start that I recently had some time to try and debug. I've been developing on Windows XP until this past week, so it was not really an issue until now.

Basically, my SDL bases game works perfectly fine on any Windows XP machine (ie. normal frame rate, shaders work no problem), but I initially noticed that if I ran the executable on Windows 7, the frame rate would only be 10-15 for no reason (on super high-end machines, ie. Phenom II X6 / 5970) but this was strictly a Windows 7 issue as indicated by testing on several different machines. Upon further investigation I realized that if I run the game from within Visual Studio 2008 on a Windows 7 machine it works perfectly (ie. 7000+ FPS w/o vsync), but as soon as I ran it from the executable instead, the frame rate would once again be between 10 and 15, and if shaders were being used via GLEW, the program would simply exit because GLEW 2.0 was unavailable.

tldr; SDL OpenGL game, works fine on XP, on Win7 works fine in VS2008 but EXE limited to 10 fps and shaders wont work

Honestly not sure what the issue could possibly be and has been baffling me for some time. If anyone has any suggestions or input, it would be greatly appreciated. It almost seems like SDL is somehow switching to software mode or some limited version of OpenGL. Also worth mentioning that the only things being rendered is some text (generated and rendered via lists) and a very simple skybox with 1024x1024 textures for each side.

My game is using SDLmain and a number of libraries, including:
SDL
SDL_ttf
GLEW
FreeImage
Qt
FMOD Ex
FBX SDK
Bullet Physics

Thanks for reading. Some code, if it helps any:

Main.cpp:
[CODE]
#include "Game.h"
int main(int argc, char * argv[]) {
Game * game = new Game();
if(!game->init()) { return -1; }
game->run();
delete game;
return 0;
}
[/CODE]

OpenGL Setup:
[CODE]
bool Game::init() {
if(m_initialized) { return false; }
settings->load();
if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER | SDL_INIT_JOYSTICK) == -1) { return false; }
SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
SDL_GL_SetAttribute(SDL_GL_SWAP_CONTROL, settings->verticalSync ? 1 : 0);
m_graphics = SDL_SetVideoMode(settings->windowWidth, settings->windowHeight, 0, SDL_OPENGL | (settings->fullScreen ? SDL_FULLSCREEN : 0));
SDL_WM_SetCaption("Game", NULL);
QString iconPath;
iconPath.append(QString("%1/Icons/Block.bmp").arg(settings->dataDirectoryName));
QByteArray iconPathBytes = iconPath.toLocal8Bit();
m_icon = SDL_LoadBMP(iconPathBytes.data());
SDL_WM_SetIcon(m_icon, NULL);
glShadeModel(GL_SMOOTH);
glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
glClearDepth(1.0f);
glEnable(GL_DEPTH_TEST);
glEnable(GL_TEXTURE_2D);
glEnable(GL_BLEND);
glDepthFunc(GL_LEQUAL);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
glMatrixMode(GL_MODELVIEW);
glViewport(0, 0, settings->windowWidth, settings->windowHeight);
if(glewInit() != GLEW_OK) { return false; }
if(!GLEW_VERSION_2_0) { return false; }

etc.
[/CODE]

Game Loop:
[CODE]
void Game::run() {
if(!m_initialized) { return; }
m_running = true;
SDL_Event event;
static unsigned int lastTime = SDL_GetTicks();
unsigned int currentTime = SDL_GetTicks();
do {
if(SDL_PollEvent(&event)) {
switch(event.type) {
case SDL_KEYDOWN:
if(!console->isActive()) {
menu->handleInput(event);
}
if(!menu->isActive()) {
console->handleInput(event);
}
break;
case SDL_MOUSEMOTION:
if(!console->isActive() &&
!menu->isActive() &&
SDL_GetAppState() & SDL_APPMOUSEFOCUS &&
SDL_GetAppState() & SDL_APPINPUTFOCUS &&
SDL_GetAppState() & SDL_APPACTIVE) {
camera->handleInput(event);
}
break;
case SDL_QUIT:
m_running = false;
break;
default:
break;
}
}
if(m_running) {
currentTime = SDL_GetTicks();
update(currentTime - lastTime);
draw();
lastTime = currentTime;
}
} while(m_running);
}
[/CODE]

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[code]if(SDL_PollEvent(&event))[/code]

Should be:

[code]while ( SDL_PollEvent( &event ) )[/code]

It's likely that your event queue accumulates more and and more windows events until your game slows down to a crawl -- you need to process all of the window messages between each frame, not just one per frame. (Not sure if this will fix your problem, but it will certainly help...)

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Oh dear, I feel ashamed for implementing that wrong. Thanks for the reply! Although this did not fix my previous issues (slow framerate, shaders unsupported), it did fix my input handling and bizarre behaviours I was experiencing with my camera which I had yet to solve, so thanks!

Still looking for a solution, though. I just can't figure what's so different with the execution of the game between being run from Visual Studio 2008 vs. from the compiled release executable.

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Are you mixing any regular SDL drawing (i.e. not OpenGL stuff) with your OpenGL drawing? That could be a possible cause on WDDM drivers.

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Not as far as I know, I'm using glLists for my SkyBox, and standard OpenGL stuff for the rest, see code below. The only strange thing I'm doing is using SDL_ttf which uses SDL_Surface to blit text which I convert to an OpenGL texture. Irregardless, I don't think any of this should be an issue if it works perfectly fine from Visual Studio 2008, right?

Edit: Furthermore, there are no problems on Windows XP when running from either VS2008 or EXE. So why is it such a problem on Windows 7? I'm using platform independent libraries (ie. no STL), so I'm still completely baffled.

SkyBox Load:
[code]
bool SkyBox::load() {
if(m_loaded) { return true; }

for(int i=0;i<6;i++) {
m_textures[i] = Game::resources->getTexture(m_textureNames[i]);
if(m_textures[i] == NULL) { return false; }
if(!m_textures[i]->load()) { return false; }
}

m_skyBoxList = glGenLists(6);

float width = (float) (m_textures[0]->getWidth() - 1) / (float) m_textures[0]->getWidth();

// left side
glNewList(m_skyBoxList, GL_COMPILE);
glBegin(GL_POLYGON);
glTexCoord2d(1 - width, width);
glVertex3d(-0.5, 0.5, 0.5);
glTexCoord2d(1 - width, 1 - width);
glVertex3d(-0.5, -0.5, 0.5);
glTexCoord2d(width, 1 - width);
glVertex3d(-0.5, -0.5, -0.5);
glTexCoord2d(width, width);
glVertex3d(-0.5, 0.5, -0.5);
glEnd();
glEndList();

// right side
glNewList(m_skyBoxList + 1, GL_COMPILE);
glBegin(GL_POLYGON);
glTexCoord2d(1 - width, width);
glVertex3d(0.5, 0.5, -0.5);
glTexCoord2d(1 - width, 1 - width);
glVertex3d(0.5, -0.5, -0.5);
glTexCoord2d(width, 1 - width);
glVertex3d(0.5, -0.5, 0.5);
glTexCoord2d(width, width);
glVertex3d(0.5, 0.5, 0.5);
glEnd();
glEndList();

// front side
glNewList(m_skyBoxList + 2, GL_COMPILE);
glBegin(GL_POLYGON);
glTexCoord2d(1 - width, width);
glVertex3d(-0.5, 0.5, -0.5);
glTexCoord2d(1 - width, 1 - width);
glVertex3d(-0.5, -0.5, -0.5);
glTexCoord2d(width, 1 - width);
glVertex3d(0.5, -0.5, -0.5);
glTexCoord2d(width, width);
glVertex3d(0.5, 0.5, -0.5);
glEnd();
glEndList();

// back side
glNewList(m_skyBoxList + 3, GL_COMPILE);
glBegin(GL_POLYGON);
glTexCoord2d(1 - width, width);
glVertex3d(0.5, 0.5, 0.5);
glTexCoord2d(1 - width, 1 - width);
glVertex3d(0.5, -0.5, 0.5);
glTexCoord2d(width, 1 - width);
glVertex3d(-0.5, -0.5, 0.5);
glTexCoord2d(width, width);
glVertex3d(-0.5, 0.5, 0.5);
glEnd();
glEndList();

// top side
glNewList(m_skyBoxList + 4, GL_COMPILE);
glBegin(GL_POLYGON);
glTexCoord2d(width, 1 - width);
glVertex3d(-0.5, 0.5, 0.5);
glTexCoord2d(width, width);
glVertex3d(-0.5, 0.5, -0.5);
glTexCoord2d(1 - width, width);
glVertex3d(0.5, 0.5, -0.5);
glTexCoord2d(1 - width, 1 - width);
glVertex3d(0.5, 0.5, 0.5);
glEnd();
glEndList();

// bottom side
glNewList(m_skyBoxList + 5, GL_COMPILE);
glBegin(GL_POLYGON);
glTexCoord2d(width, 1 - width);
glVertex3d(-0.5, -0.5, -0.5);
glTexCoord2d(width, width);
glVertex3d(-0.5, -0.5, 0.5);
glTexCoord2d(1 - width, width);
glVertex3d(0.5, -0.5, 0.5);
glTexCoord2d(1 - width, 1 - width);
glVertex3d(0.5, -0.5, -0.5);
glEnd();
glEndList();

m_loaded = true;

return true;
}
[/code]

SkyBox Draw:
[code]
void SkyBox::draw() {
if(!m_loaded) { return; }

glDisable(GL_DEPTH_TEST);

glLoadIdentity();

glRotated(Game::camera->getRotation().x, 1, 0, 0);
glRotated(Game::camera->getRotation().y, 0, 1, 0);

for(int i=0;i<6;i++) {
m_textures[i]->activate();
glCallList(m_skyBoxList + i);
}

glEnable(GL_DEPTH_TEST);
}
[/code]

Game Draw:
[code]
void Game::draw() {
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

// set up 3d rendering
glEnable(GL_TEXTURE_2D);
glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(70.0f, (GLfloat) settings->windowWidth / (GLfloat) settings->windowHeight, 0.1f, 10000.0f);
glMatrixMode(GL_MODELVIEW);

// render skybox
if(skyBox != NULL) {
skyBox->draw();
}

// render world
if(mainShader != NULL) { mainShader->activate(); }

glPushMatrix();
camera->setup();

glScalef(100, 100, 100);

glBegin(GL_POLYGON);

// left
glVertex3f(-1.0f, 0.0f, 0.0f);
glVertex3f(-1.0f, 0.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, 0.0f);

// right
glVertex3f(0.0f, 0.0f, 0.0f);
glVertex3f(0.0f, -1.0f, 0.0f);
glVertex3f(0.0f, -1.0f, -1.0f);
glVertex3f(0.0f, 0.0f, -1.0f);

// front
glVertex3f(0.0f, 0.0f, 0.0f);
glVertex3f(-1.0f, 0.0f, 0.0f);
glVertex3f(-1.0f, -1.0f, 0.0f);
glVertex3f(0.0f, -1.0f, 0.0f);

// back
glVertex3f(0.0f, 0.0f, 0.0f);
glVertex3f(-1.0f, 0.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, -1.0f);
glVertex3f(0.0f, -1.0f, -1.0f);

// top
glVertex3f(0.0f, 0.0f, 0.0f);
glVertex3f(0.0f, 0.0f, -1.0f);
glVertex3f(-1.0f, 0.0f, -1.0f);
glVertex3f(-1.0f, 0.0f, 0.0f);

// bottom
glVertex3f(0.0f, 0.0f, 0.0f);
glVertex3f(0.0f, -1.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, 0.0f);

glEnd();
glPopMatrix();

if(mainShader != NULL) { mainShader->deactivate(); }

// set up 2d rendering
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(0, settings->windowWidth, settings->windowHeight, 0);

// render hud / gui elements
displayFPS();
menu->draw();
console->draw();

SDL_GL_SwapBuffers();
}
[/code]

Font Draw / Load:
[code]
void Font::drawTextHelper(int x, int y, const char * text) const {
if(!m_loaded) { return; }

glEnable(GL_TEXTURE_2D);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE);

glBindTexture(GL_TEXTURE_2D, m_texture);

glMatrixMode(GL_MODELVIEW);
glPushMatrix();

glLoadIdentity();

glTranslated(x, y, 0);
glListBase(m_font - 32);
glCallLists(strlen(text), GL_BYTE, text);

glPopMatrix();
}

bool Font::load() {
if(m_loaded) { return true; }

QString fontPath = QString("%1/Fonts/%2").arg(Game::settings->dataDirectoryName).arg(m_fileName);

QFileInfo fontFile(fontPath);
if(!fontFile.exists()) { return false; }

QByteArray bytes = fontPath.toLocal8Bit();

TTF_Font * fontData;
if(!(fontData = TTF_OpenFont(bytes.data(), m_size))) {
return false;
}

SDL_Color colour = {255, 255, 255, 255};

SDL_Surface * character;
QVector characters;
int maxWidth = -1;
int maxHeight = -1;
char data[2];
data[1] = '\0';
for(int i=0;i<128;i++ ) {
data[0] = (char) (i + 32);
character = TTF_RenderText_Blended(fontData, data, colour);
characters.push_back(character);
if(maxWidth < 0 || maxWidth < character->w) { maxWidth = character->w; }
if(maxHeight < 0 || maxHeight < character->h) { maxHeight = character->h; }
}

m_horizontalSpacing = maxWidth;
m_verticalSpacing = maxHeight;

int width = 1, tempWidth = maxWidth * 16;
int height = 1, tempHeight = maxHeight * 8;
while(width < tempWidth) { width *= 2; }
while(height < tempHeight) { height *= 2; }

SDL_Surface * temp = SDL_CreateRGBSurface(0, width, height, 32,
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff
#else
0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000
#endif
);

SDL_Rect sourceArea, destArea;
int x = 0;
int y = 0;
for(int i=0;i<128;i++) {
sourceArea.x = 0;
sourceArea.y = 0;
sourceArea.w = characters[i]->w;
sourceArea.h = characters[i]->h;

destArea.x = maxWidth * x;
destArea.y = maxHeight * y;
destArea.w = characters[i]->w;
destArea.h = characters[i]->h;

SDL_SetAlpha(characters[i], 0, 0);
SDL_BlitSurface(characters[i], &sourceArea, temp, &destArea);

x++;
if(x == 16) {
x = 0;
y++;
}
}

glGenTextures(1, &m_texture);
glBindTexture(GL_TEXTURE_2D, m_texture);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, temp->w, temp->h, 0, GL_RGBA, GL_UNSIGNED_BYTE, temp->pixels);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

glEnable(GL_TEXTURE_2D);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE);

m_font = glGenLists(128);

x = 0;
y = 0;
float w = (float) maxWidth / (float) (temp->w);
float h = (float) maxHeight / (float) (temp->h);
for(int i=0;i<128;i++) {

glNewList(m_font + i, GL_COMPILE);

glBegin(GL_QUADS);
glTexCoord2f((w * x), ((h * y))); glVertex2i(0, 0);
glTexCoord2f((w * x) + w, ((h * y))); glVertex2i(maxWidth, 0);
glTexCoord2f((w * x) + w, ((h * y) + h)); glVertex2i(maxWidth, maxHeight);
glTexCoord2f((w * x), ((h * y) + h)); glVertex2i(0, maxHeight);
glEnd();

glTranslated(maxWidth, 0, 0);

glEndList();

x++;
if(x == 16) {
x = 0;
y++;
}
}

for(int i=0;i<128;i++) {
SDL_FreeSurface(characters[i]);
}
SDL_FreeSurface(temp);

m_loaded = true;

return true;
}
[/code]

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Found the solution to all my issues finally, after consulting some friends. Turns out Visual Studio 2008 on Windows 7 would use the operating system's version of OpenGL, and when I ran it from the EXE it used the local OpenGL32.dll which was either out of date, or built for the wrong platform. So, removing this DLL fixed all framerate issues, and now runs no problem after defaulting to the operating system's OpenGL32.dll. Hopefully this helps anyone else who runs into this issue!

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    • By TheChubu
      The Khronos™ Group, an open consortium of leading hardware and software companies, announces from the SIGGRAPH 2017 Conference the immediate public availability of the OpenGL® 4.6 specification. OpenGL 4.6 integrates the functionality of numerous ARB and EXT extensions created by Khronos members AMD, Intel, and NVIDIA into core, including the capability to ingest SPIR-V™ shaders.
      SPIR-V is a Khronos-defined standard intermediate language for parallel compute and graphics, which enables content creators to simplify their shader authoring and management pipelines while providing significant source shading language flexibility. OpenGL 4.6 adds support for ingesting SPIR-V shaders to the core specification, guaranteeing that SPIR-V shaders will be widely supported by OpenGL implementations.
      OpenGL 4.6 adds the functionality of these ARB extensions to OpenGL’s core specification:
      GL_ARB_gl_spirv and GL_ARB_spirv_extensions to standardize SPIR-V support for OpenGL GL_ARB_indirect_parameters and GL_ARB_shader_draw_parameters for reducing the CPU overhead associated with rendering batches of geometry GL_ARB_pipeline_statistics_query and GL_ARB_transform_feedback_overflow_querystandardize OpenGL support for features available in Direct3D GL_ARB_texture_filter_anisotropic (based on GL_EXT_texture_filter_anisotropic) brings previously IP encumbered functionality into OpenGL to improve the visual quality of textured scenes GL_ARB_polygon_offset_clamp (based on GL_EXT_polygon_offset_clamp) suppresses a common visual artifact known as a “light leak” associated with rendering shadows GL_ARB_shader_atomic_counter_ops and GL_ARB_shader_group_vote add shader intrinsics supported by all desktop vendors to improve functionality and performance GL_KHR_no_error reduces driver overhead by allowing the application to indicate that it expects error-free operation so errors need not be generated In addition to the above features being added to OpenGL 4.6, the following are being released as extensions:
      GL_KHR_parallel_shader_compile allows applications to launch multiple shader compile threads to improve shader compile throughput WGL_ARB_create_context_no_error and GXL_ARB_create_context_no_error allow no error contexts to be created with WGL or GLX that support the GL_KHR_no_error extension “I’m proud to announce OpenGL 4.6 as the most feature-rich version of OpenGL yet. We've brought together the most popular, widely-supported extensions into a new core specification to give OpenGL developers and end users an improved baseline feature set. This includes resolving previous intellectual property roadblocks to bringing anisotropic texture filtering and polygon offset clamping into the core specification to enable widespread implementation and usage,” said Piers Daniell, chair of the OpenGL Working Group at Khronos. “The OpenGL working group will continue to respond to market needs and work with GPU vendors to ensure OpenGL remains a viable and evolving graphics API for all its customers and users across many vital industries.“
      The OpenGL 4.6 specification can be found at https://khronos.org/registry/OpenGL/index_gl.php. The GLSL to SPIR-V compiler glslang has been updated with GLSL 4.60 support, and can be found at https://github.com/KhronosGroup/glslang.
      Sophisticated graphics applications will also benefit from a set of newly released extensions for both OpenGL and OpenGL ES to enable interoperability with Vulkan and Direct3D. These extensions are named:
      GL_EXT_memory_object GL_EXT_memory_object_fd GL_EXT_memory_object_win32 GL_EXT_semaphore GL_EXT_semaphore_fd GL_EXT_semaphore_win32 GL_EXT_win32_keyed_mutex They can be found at: https://khronos.org/registry/OpenGL/index_gl.php
      Industry Support for OpenGL 4.6
      “With OpenGL 4.6 our customers have an improved set of core features available on our full range of OpenGL 4.x capable GPUs. These features provide improved rendering quality, performance and functionality. As the graphics industry’s most popular API, we fully support OpenGL and will continue to work closely with the Khronos Group on the development of new OpenGL specifications and extensions for our customers. NVIDIA has released beta OpenGL 4.6 drivers today at https://developer.nvidia.com/opengl-driver so developers can use these new features right away,” said Bob Pette, vice president, Professional Graphics at NVIDIA.
      "OpenGL 4.6 will be the first OpenGL release where conformant open source implementations based on the Mesa project will be deliverable in a reasonable timeframe after release. The open sourcing of the OpenGL conformance test suite and ongoing work between Khronos and X.org will also allow for non-vendor led open source implementations to achieve conformance in the near future," said David Airlie, senior principal engineer at Red Hat, and developer on Mesa/X.org projects.

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    • By _OskaR
      Hi,
      I have an OpenGL application but without possibility to wite own shaders.
      I need to perform small VS modification - is possible to do it in an alternative way? Do we have apps or driver modifictions which will catch the shader sent to GPU and override it?
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