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GRIM: Use an ARB shader to dim a screen region if possible.

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This is much faster than using glReadPixels/glDrawPixels.
This commit is contained in:
Giulio Camuffo 2012-03-07 16:12:14 +01:00
parent 45ecf07bce
commit aeedfb4aa3
2 changed files with 99 additions and 2 deletions
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99
engines/grim/gfx_opengl.cpp
View file

@ -57,6 +57,7 @@ PFNGLGENPROGRAMSARBPROC glGenProgramsARB;
PFNGLBINDPROGRAMARBPROC glBindProgramARB;
PFNGLPROGRAMSTRINGARBPROC glProgramStringARB;
PFNGLDELETEPROGRAMSARBPROC glDeleteProgramsARB;
PFNGLPROGRAMLOCALPARAMETER4FARBPROC glProgramLocalParameter4fARB;
#endif
@ -74,6 +75,23 @@ static char fragSrc[] =
MOV result.depth, d.r;\n\
END\n";
static char dimFragSrc[] =
"!!ARBfp1.0\n\
PARAM level = program.local[0];\n\
TEMP color;\n\
TEMP d;\n\
TEX d, fragment.texcoord[0], texture[0], 2D;\n\
TEMP sum;\n\
MOV sum, d.r;\n\
ADD sum, sum, d.g;\n\
ADD sum, sum, d.b;\n\
MUL sum, sum, 0.33;\n\
MUL sum, sum, level.x;\n\
MOV result.color.r, sum;\n\
MOV result.color.g, sum;\n\
MOV result.color.b, sum;\n\
END\n";
GfxOpenGL::GfxOpenGL() {
g_driver = this;
_storedDisplay = NULL;
@ -89,6 +107,9 @@ GfxOpenGL::~GfxOpenGL() {
#ifdef GL_ARB_fragment_program
if (_useDepthShader)
glDeleteProgramsARB(1, &_fragmentProgram);
if (_useDimShader)
glDeleteProgramsARB(1, &_dimFragProgram);
#endif
}
@ -102,6 +123,7 @@ byte *GfxOpenGL::setupScreen(int screenW, int screenH, bool fullscreen) {
_isFullscreen = g_system->getFeatureState(OSystem::kFeatureFullscreenMode);
_useDepthShader = false;
_useDimShader = false;
g_system->showMouse(!fullscreen);
@ -148,10 +170,13 @@ void GfxOpenGL::initExtensions()
glProgramStringARB = (PFNGLPROGRAMSTRINGARBPROC)u.func_ptr;
u.obj_ptr = SDL_GL_GetProcAddress("glDeleteProgramsARB");
glDeleteProgramsARB = (PFNGLDELETEPROGRAMSARBPROC)u.func_ptr;
u.obj_ptr = SDL_GL_GetProcAddress("glProgramLocalParameter4fARB");
glProgramLocalParameter4fARB = (PFNGLPROGRAMLOCALPARAMETER4FARBPROC)u.func_ptr;
const char* extensions = (const char*)glGetString(GL_EXTENSIONS);
if (strstr(extensions, "ARB_fragment_program")) {
_useDepthShader = true;
_useDimShader = true;
}
if (_useDepthShader) {
@ -162,9 +187,20 @@ void GfxOpenGL::initExtensions()
glProgramStringARB(GL_FRAGMENT_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB, strlen(fragSrc), fragSrc);
glGetIntegerv(GL_PROGRAM_ERROR_POSITION_ARB, &errorPos);
if (errorPos != -1) {
warning("Error compiling fragment program:\n%s", glGetString(GL_PROGRAM_ERROR_STRING_ARB));
warning("Error compiling depth fragment program:\n%s", glGetString(GL_PROGRAM_ERROR_STRING_ARB));
_useDepthShader = false;
}
glGenProgramsARB(1, &_dimFragProgram);
glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, _dimFragProgram);
glProgramStringARB(GL_FRAGMENT_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB, strlen(dimFragSrc), dimFragSrc);
glGetIntegerv(GL_PROGRAM_ERROR_POSITION_ARB, &errorPos);
if (errorPos != -1) {
warning("Error compiling dim fragment program:\n%s", glGetString(GL_PROGRAM_ERROR_STRING_ARB));
_useDimShader = false;
}
}
#endif
}
@ -780,6 +816,7 @@ void GfxOpenGL::drawBitmap(const Bitmap *bitmap, int dx, int dy) {
glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
glDepthMask(GL_TRUE);
#ifdef GL_ARB_fragment_program
glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, _fragmentProgram);
glEnable(GL_FRAGMENT_PROGRAM_ARB);
#endif
}
@ -1303,8 +1340,66 @@ void GfxOpenGL::dimRegion(int x, int yReal, int w, int h, float level) {
yReal = (int)(yReal *_scaleH);
w = (int)(w * _scaleW);
h = (int)(h * _scaleH);
int y = _screenHeight - yReal - h;
#ifdef GL_ARB_fragment_program
if (_useDimShader) {
GLuint texture;
glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
glTexImage2D(GL_TEXTURE_2D, 0, 3, w, h, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glViewport(0, 0, _screenWidth, _screenHeight);
// copy the data over to the texture
glBindTexture(GL_TEXTURE_2D, texture);
glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, x, y, w, h, 0);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0, _screenWidth, 0, _screenHeight, 0, 1);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glMatrixMode(GL_TEXTURE);
glLoadIdentity();
glDisable(GL_LIGHTING);
glDisable(GL_DEPTH_TEST);
glDisable(GL_ALPHA_TEST);
glDepthMask(GL_FALSE);
glEnable(GL_SCISSOR_TEST);
glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, _dimFragProgram);
glEnable(GL_FRAGMENT_PROGRAM_ARB);
glProgramLocalParameter4fARB(GL_FRAGMENT_PROGRAM_ARB, 0, level, 0, 0, 0);
glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, texture);
glBegin(GL_QUADS);
glTexCoord2f(0, 0);
glVertex2f(x, y);
glTexCoord2f(1.0f, 0.0f);
glVertex2f(x + w, y);
glTexCoord2f(1.0f, 1.0f);
glVertex2f(x + w, y + h);
glTexCoord2f(0.0f, 1.0f);
glVertex2f(x, y + h);
glEnd();
glDisable(GL_FRAGMENT_PROGRAM_ARB);
glDeleteTextures(1, &texture);
return;
}
#endif
uint32 *data = new uint32[w * h];
int y = _screenHeight - yReal;
y = _screenHeight - yReal;
// collect the requested area and generate the dimmed version
glReadPixels(x, y - h, w, h, GL_RGBA, GL_UNSIGNED_BYTE, data);

2
engines/grim/gfx_opengl.h
View file

@ -131,6 +131,8 @@ private:
byte *_storedDisplay;
bool _useDepthShader;
GLuint _fragmentProgram;
bool _useDimShader;
GLuint _dimFragProgram;
int _maxLights;
};