X-Git-Url: http://shamusworld.gotdns.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fsdlemu_opengl.c;h=348982297f1c2f2c787919d584f0033ca114db8a;hb=f3e5bb2807319c210d124d6150e019130c54867b;hp=41f92a77f3cad8becb77b746f2dd6c07e764a46f;hpb=413aeb099b2982e60bc095a7e404fd2fefff4d7f;p=virtualjaguar diff --git a/src/sdlemu_opengl.c b/src/sdlemu_opengl.c index 41f92a7..3489822 100644 --- a/src/sdlemu_opengl.c +++ b/src/sdlemu_opengl.c @@ -1,6 +1,6 @@ /* * SDLEMU library - Free sdl related functions library - * Copyrigh(c) 1999-2002 sdlemu development crew + * Copyrigh(c) 1999-2004 sdlemu development crew * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -16,23 +16,49 @@ * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ - -/* + +/* SDLEMU_OPENGL.C + SDLEMU related sources for using OpenGL with SDL. + By Niels Wagenaar | http://sdlemu.ngemu.com | shalafi@xs4all.nl + Version 1.0.001 - 4-10-2004 - - - Added support for 16, 24 and 32 bit textures * new *; - - Added support for 16, 24 and 32 bit texture rendering *new*; + + - Added support for 16, 24 and 32 bit textures; + - Added support for 16, 24 and 32 bit texture rendering; + + Version 1.0.002 - 6-10-2004 + + - Cleaned up a lot of code and removed non functional and obsolete code; + - Removed sdlemu_resize_texture function because of double code; + - Removed the texture creation from the sdlemu_init_opengl; + - Added sdlemu_create_texture function to replace the sdlemu_resize_texture function + and the texture creation in sdlemu_init_opengl; + - Added the usage of OPENGL_16BPP_CORRECT_RGBA for activating the correct 16bpp RGBA masks; + - Added the usage of WANT_OPENGL_ALPHA for using ALPHA blending with 32bpp textures; + - Added automatic and override texture bpp depth setting (based upon the src surface); */ #include "sdlemu_opengl.h" +// We want alpha on our OpenGL contexts...! +// Or do we? Seems to kill performance on X... +// Or does it? Could it be bad blitter performance? +#define WANT_OPENGL_ALPHA + static SDL_Surface *texture = 0; static GLuint texid = 0; static GLfloat texcoord[4]; static unsigned int glFilter; static unsigned int texturebpp = 0; // 16, 24 or 32 bpp +static SDL_Surface * overlay = 0; +static GLuint overlayID = 0; +static GLfloat overlayCoord[4]; +void sdlemu_create_overlay(SDL_Surface * dst, int src_bpp); + +static int showOverlay = 0; + static inline int power_of_two(int input) { int value = 1; @@ -43,24 +69,13 @@ static inline int power_of_two(int input) return value; } -void sdlemu_init_opengl(SDL_Surface * src, int texturetype, float size, int filter, int src_bpp) +void sdlemu_init_opengl(SDL_Surface * src, SDL_Surface * dst, int texturetype, int filter, int src_bpp) { - int w, h; - Uint32 rmask, gmask, bmask, amask; - - // We allow the developer to set its own texture bpp. But if the value is NULL or - // not equal to 16, 24 or 32, we make the texturebpp the same as the BPP from src. - if ( (src_bpp != NULL) && ( (src_bpp == 16) || (src_bpp == 24) || (src_bpp == 32) ) ) - texturebpp = src_bpp; - else - texturebpp = src->format->BitsPerPixel; - printf("\nOpenGL driver information :\n"); printf("\n"); printf("Vendor: %s\n", glGetString(GL_VENDOR)); printf("Renderer: %s\n", glGetString(GL_RENDERER)); printf("Version: %s\n", glGetString(GL_VERSION)); - printf("OpenGL Texture BPP: %d\n", texturebpp); printf("OpenGL drawmethod: "); switch (texturetype) @@ -75,213 +90,122 @@ void sdlemu_init_opengl(SDL_Surface * src, int texturetype, float size, int filt glFilter = filter; - // Texture width/height should be power of 2 - // So, find the largest power of two that will contain both the width and height - // w = power_of_two(src->w); - // h = power_of_two(src->h); - w = 512; - h = 512; - - switch ( texturebpp ) - { - case 16: - #if SDL_BYTEORDER == SDL_BIG_ENDIAN - -// rmask = 0xff000000; -// gmask = 0x00ff0000; -// bmask = 0x0000ff00; -// amask = 0x00000000; - - rmask = 0x0000; - gmask = 0x0000; - bmask = 0x0000; - amask = 0x0000; - - #else - -// rmask = 0x000000ff; -// gmask = 0x0000ff00; -// bmask = 0x00ff0000; -// amask = 0x00000000; - - rmask = 0x0000; - gmask = 0x0000; - bmask = 0x0000; - amask = 0x0000; - - #endif - - break; - case 24: - #if SDL_BYTEORDER == SDL_BIG_ENDIAN - rmask = 0x00ff0000; - gmask = 0x0000ff00; - bmask = 0x000000ff; - amask = 0x00000000; - #else - rmask = 0x000000ff; - gmask = 0x0000ff00; - bmask = 0x00ff0000; - amask = 0x00000000; - #endif - break; - case 32: - default: - #if SDL_BYTEORDER == SDL_BIG_ENDIAN - rmask = 0xff000000; - gmask = 0x00ff0000; - bmask = 0x0000ff00; - amask = 0x000000ff; - #else - rmask = 0x000000ff; - gmask = 0x0000ff00; - bmask = 0x00ff0000; - amask = 0xff000000; - #endif - break; - } - - // create texture surface - texture = SDL_CreateRGBSurface(SDL_SWSURFACE, w, h, texturebpp, rmask, gmask, bmask, amask); -/* - #if SDL_BYTEORDER == SDL_LIL_ENDIAN - 0x000000FF, 0x0000FF00, 0x00FF0000, 0xFF000000); - #else - 0xFF000000, 0x00FF0000, 0x0000FF00, 0x000000FF); - #endif -*/ - - // setup 2D gl environment - //glPushAttrib(GL_ENABLE_BIT); - //glDisable(GL_DEPTH_TEST); - //glDisable(GL_CULL_FACE); - //glEnable(GL_TEXTURE_2D); - - glDisable(GL_FOG); - glDisable(GL_LIGHTING); - glDisable(GL_CULL_FACE); - glDisable(GL_DEPTH_TEST); - glDisable(GL_BLEND); - glDisable(GL_NORMALIZE); - glDisable(GL_ALPHA_TEST); - glEnable(GL_TEXTURE_2D); - glBlendFunc (GL_SRC_ALPHA, GL_ONE); - - glViewport(0, 0, src->w * size, src->h * size); - - glMatrixMode(GL_PROJECTION); - glPushMatrix(); - glLoadIdentity(); - - glOrtho(0.0, (GLdouble)(src->w * size), (GLdouble)(src->h * size), 0.0, 0.0, 1.0); - glMatrixMode(GL_MODELVIEW); - glPushMatrix(); - glLoadIdentity(); - - // texture coordinates - texcoord[0] = 0.0f; - texcoord[1] = 0.0f; - texcoord[2] = (GLfloat)(src->w) / texture->w; - texcoord[3] = (GLfloat)(src->h) / texture->h; - - // create an RGBA texture for the texture surface - glGenTextures(1, &texid); - glBindTexture(GL_TEXTURE_2D, texid); - - if (glFilter) - { - printf("OpenGL filters: enabled\n"); - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); - } - else - { - printf("OpenGL filters: disabled\n"); - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); - } - - switch ( texturebpp ) - { - case 16: - glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB5, texture->w, texture->h, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL); - break; - case 24: - glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, texture->w, texture->h, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL); - break; - case 32: - default: - glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, texture->w, texture->h, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL); - break; - } - + // Let us create the texture information : + sdlemu_create_texture(src, dst, filter, src_bpp); + sdlemu_create_overlay(dst, src_bpp); } void sdlemu_draw_texture(SDL_Surface * dst, SDL_Surface * src, int texturetype) { - //SDL_Rect rect = { 0, 0, src->w, src->h }; +/* + This is needed when we want to render OpenGL textures with the Alpha mask set. + Be warned! This only works with the bpp of texture en *src set to 32. +*/ +#ifdef WANT_OPENGL_ALPHA + Uint32 saved_flags; + Uint8 saved_alpha; + + /* Save the alpha blending attributes */ + saved_flags = src->flags&(SDL_SRCALPHA|SDL_RLEACCELOK); + saved_alpha = src->format->alpha; + if ( (saved_flags & SDL_SRCALPHA) == SDL_SRCALPHA ) { + SDL_SetAlpha(src, 0, 0); + } - // convert color-indexed surface to RGB texture - //SDL_BlitSurface(src, &rect, texture, &rect); - //glFlush(); - + // Blit the src display to the texture. SDL_BlitSurface(src, NULL, texture, NULL); -// printf("Rmask - src : %d\n", src->format->Rmask); -// printf("Gmask - src : %d\n", src->format->Gmask); -// printf("Bmask - src : %d\n", src->format->Bmask); -// printf("Amask - src : %d\n", src->format->Amask); - -// printf("Rmask - texture : %d\n", texture->format->Rmask); -// printf("Gmask - texture : %d\n", texture->format->Gmask); -// printf("Bmask - texture : %d\n", texture->format->Bmask); -// printf("Amask - texture : %d\n", texture->format->Amask); - - // Texturemap complete texture to surface so we have free scaling + /* Restore the alpha blending attributes */ + if ( (saved_flags & SDL_SRCALPHA) == SDL_SRCALPHA ) { + SDL_SetAlpha(src, saved_flags, saved_alpha); + } +#else + SDL_BlitSurface(src, NULL, texture, NULL); +#endif +// SDL_BlitSurface(src, NULL, overlay, NULL); +/*Uint32 * pix = (Uint32 *)overlay->pixels; +Uint32 y,x; +for(y=10; y<200; y++) +for(x=30; x<250; x++) +pix[x+(y*1024)] = 0x800000FF;//*/ + +glBlendFunc(GL_ONE, GL_ZERO); +glBindTexture(GL_TEXTURE_2D, texid); + // Texturemap complete texture to surface so we have free scaling // and antialiasing - switch ( texturebpp ) - { - case 16: - // GL_UNSIGNED_SHORT_5_6_5 - glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, texture->w, texture->h, - GL_RGB, GL_UNSIGNED_SHORT_5_6_5, texture->pixels); - break; - case 24: - glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, texture->w, texture->h, - GL_RGB, GL_UNSIGNED_BYTE, texture->pixels); - break; - case 32: - default: - glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, texture->w, texture->h, - GL_RGBA, GL_UNSIGNED_BYTE, texture->pixels); - break; - } - + switch (texturebpp) + { + case 16: + glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, texture->w, texture->h, + GL_RGB, GL_UNSIGNED_SHORT_5_6_5, texture->pixels); + break; + case 24: + glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, texture->w, texture->h, + GL_RGB, GL_UNSIGNED_BYTE, texture->pixels); + break; + case 32: + default: + glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, texture->w, texture->h, + GL_RGBA, GL_UNSIGNED_BYTE, texture->pixels); + break; + } + + // Render the texture to the screen using OpenGL! switch (texturetype) { case 1: - glBegin(GL_QUADS); - glTexCoord2f(texcoord[0], texcoord[1]); - glVertex2f(0, 0); - glTexCoord2f(texcoord[2], texcoord[1]); - glVertex2f(dst->w , 0); - glTexCoord2f(texcoord[2], texcoord[3]); - glVertex2f(dst->w , dst->h ); - glTexCoord2f(texcoord[0], texcoord[3]); - glVertex2f(0, dst->h ); - glEnd(); + glBegin(GL_QUADS); + glTexCoord2f(texcoord[0], texcoord[1]); + glVertex2f(0, 0); + glTexCoord2f(texcoord[2], texcoord[1]); + glVertex2f(dst->w, 0); + glTexCoord2f(texcoord[2], texcoord[3]); + glVertex2f(dst->w, dst->h); + glTexCoord2f(texcoord[0], texcoord[3]); + glVertex2f(0, dst->h); + glEnd(); default: glBegin(GL_TRIANGLE_STRIP); - glTexCoord2f(texcoord[0], texcoord[1]); glVertex3i(0, 0, 0); - glTexCoord2f(texcoord[2], texcoord[1]); glVertex3i(dst->w, 0, 0); - glTexCoord2f(texcoord[0], texcoord[3]); glVertex3i(0, dst->h, 0); - glTexCoord2f(texcoord[2], texcoord[3]); glVertex3i(dst->w, dst->h, 0); + glTexCoord2f(texcoord[0], texcoord[1]); glVertex3i(0, 0, 0); + glTexCoord2f(texcoord[2], texcoord[1]); glVertex3i(dst->w, 0, 0); + glTexCoord2f(texcoord[0], texcoord[3]); glVertex3i(0, dst->h, 0); + glTexCoord2f(texcoord[2], texcoord[3]); glVertex3i(dst->w, dst->h, 0); + glEnd(); + }//*/ + + if (showOverlay) + { + glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); + glBindTexture(GL_TEXTURE_2D, overlayID); + glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, overlay->w, overlay->h, GL_RGBA, GL_UNSIGNED_BYTE, overlay->pixels); + glBegin(GL_QUADS); + glTexCoord2f(overlayCoord[0], overlayCoord[1]); + glVertex2f(0, 0); + glTexCoord2f(overlayCoord[2], overlayCoord[1]); + glVertex2f(dst->w, 0); + glTexCoord2f(overlayCoord[2], overlayCoord[3]); + glVertex2f(dst->w, dst->h); + glTexCoord2f(overlayCoord[0], overlayCoord[3]); + glVertex2f(0, dst->h); glEnd(); } - + +//Do some OpenGL stuff here... +//Doesn't work... +/*unsigned long int map[25] = { + 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, + 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, + 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, + 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, + 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF +}; +glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); +glRasterPos2i(10, 10); +glDrawPixels(5, 5, GL_RGBA, GL_UNSIGNED_INT, map);//*/ + // glFlush(); - SDL_GL_SwapBuffers(); + SDL_GL_SwapBuffers(); // glFinish(); } @@ -290,178 +214,327 @@ void sdlemu_close_opengl(void) { if (texture) SDL_FreeSurface(texture); -} + if (overlay) + SDL_FreeSurface(overlay); +} -// -// Resize the texture -// This should honor the glFilter flag that is passed in to the initialization code, -// but, at the moment, it doesn't... -// Now it does...! -// -void sdlemu_resize_texture(SDL_Surface * src, SDL_Surface * dst, int filter, int src_bpp) +void sdlemu_create_overlay(SDL_Surface * dst, int src_bpp) { - // Texture width/height should be power of 2 + // Local variables. + Uint32 rmask, gmask, bmask, amask; // Needed for creating RGBA masks. + + // Delete old texture (if allocated). Useful when there is a screen resize. + if (overlay) + SDL_FreeSurface(overlay); + + // Texture width/height should be power of 2 of the SDL_Surface *src when using OpenGL. // So, find the largest power of two that will contain both the width and height - //int w = power_of_two(src->w), h = power_of_two(src->h); - int w = 512, h = 512; - Uint32 rmask, gmask, bmask, amask; - + int w = power_of_two(dst->w); + int h = power_of_two(dst->h); + + printf("OpenGL - Overlay size : %d x %d\n", w, h); + + // Setting bpp based upon src_bpp. + int bpp = src_bpp; + // We allow the developer to set its own texture bpp. But if the value is NULL or // not equal to 16, 24 or 32, we make the texturebpp the same as the BPP from src. - if ( (src_bpp != NULL) && ( (src_bpp == 16) || (src_bpp == 24) || (src_bpp == 32) ) ) - texturebpp = src_bpp; - else - texturebpp = src->format->BitsPerPixel; - - // Delete old texture (if allocated) - if (texture) - SDL_FreeSurface(texture); + if (bpp == 16 || bpp == 24 || bpp == 32) + texturebpp = bpp; + else + texturebpp = dst->format->BitsPerPixel; + + printf("OpenGL - Overlay depth : %d bpp\n", texturebpp); - // create texture surface - //NOTE: Seems the byte order here *is* important! (Perhaps only for 32 BPP?) + // Now were are going to create a SDL_Surface named texture. This will be our surface + // which will function as a buffer between the SDL_Surface *src and SDL_Surface *dst. + // This buffer is needed because we need to convert the SDL_Surface *src to an OpenGL + // texture with a depth of 16, 24 or 32 bpp, before we can blit the pixels to *dst + // using OpenGL. // - // NOTE : Nope! Not any more. We can now producte textures based upon 16, 24 or 32 bpp. - switch ( texturebpp ) + // NOTE: Seems the byte order here *is* important! + switch (texturebpp) { - case 16: - #if SDL_BYTEORDER == SDL_BIG_ENDIAN - -// rmask = 0xff000000; -// gmask = 0x00ff0000; -// bmask = 0x0000ff00; -// amask = 0x00000000; + case 16: // *src has depth of 16 bpp +/* + According to information on the SDL mailinglist and on internet, the following + rgba masks should be the ones to use. But somehow the screen gets f*cked up and + the RGB colours are incorrect (at least in Virtual Jaguar/SDL). - rmask = 0x0000; + Compile with -DOPENGL_16BPP_CORRECT_RGBA to use this RGBA values. +*/ +#ifdef OPENGL_16BPP_CORRECT_RGBA + rmask = 0x7C00; + gmask = 0x03E0; + bmask = 0x001F; + amask = 0x0000; +#else + rmask = 0x0000; gmask = 0x0000; bmask = 0x0000; amask = 0x0000; - +#endif + break; + case 24: // *src has depth of 24 bpp + #if SDL_BYTEORDER == SDL_BIG_ENDIAN + rmask = 0x00FF0000; + gmask = 0x0000FF00; + bmask = 0x000000FF; + amask = 0x00000000; // IMPORTANT! 24 bpp doesn't use Alpha (at least in our case). + #else + rmask = 0x000000FF; + gmask = 0x0000FF00; + bmask = 0x00FF0000; + amask = 0x00000000; // IMPORTANT! 24 bpp doesn't use Alpha (at least in our case). + #endif + break; + case 32: //*src has depth of 32 bpp + default: //which is also the default. + #if SDL_BYTEORDER == SDL_BIG_ENDIAN + rmask = 0xFF000000; + gmask = 0x00FF0000; + bmask = 0x0000FF00; + amask = 0x000000FF; #else + rmask = 0x000000FF; + gmask = 0x0000FF00; + bmask = 0x00FF0000; + amask = 0xFF000000; + #endif + break; + } + + // Creating SDL_Surface texture based upon the above settings. + overlay = SDL_CreateRGBSurface(SDL_SWSURFACE, w, h, texturebpp, rmask, gmask, bmask, amask); + + // Setting up the texture coordinates. + overlayCoord[0] = 0.0f; + overlayCoord[1] = 0.0f; + overlayCoord[2] = (GLfloat)(dst->w) / overlay->w; + overlayCoord[3] = (GLfloat)(dst->h) / overlay->h; + + // create a RGB(A) texture for the texture surface + glGenTextures(1, &overlayID); + glBindTexture(GL_TEXTURE_2D, overlayID); -// rmask = 0x000000ff; -// gmask = 0x0000ff00; -// bmask = 0x00ff0000; -// amask = 0x00000000; + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); + + // Setting texture mode. + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP); + + // Generate the texture using the above information. + switch (texturebpp) + { + case 16: + // Normal 16bpp depth based textures consist out of GL_RGB5 and doesn't have support for Alpha channels. + glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB5, overlay->w, overlay->h, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL); + break; + case 24: + // The 24bpp depth based textures consist out of GL_RGB8 and doesn't have support for Alpha channels. + // + // IMPORTANT : If you don't use Alpha. Use textures with a depth of 16bpp. + // If you use Alpha. Use textures with a depth of 32bpp. + // 24bpp textures are SLOW and avoid them at all costs! + glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, overlay->w, overlay->h, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL); + break; + case 32: + default: + // The 32bpp depth based textures consist out of GL_RGBA8 and has support for Alpha channels. + glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, overlay->w, overlay->h, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL); + break; + } +} + +void * sdlemuGetOverlayPixels(void) +{ + return overlay->pixels; +} + +Uint32 sdlemuGetOverlayWidthInPixels(void) +{ + return overlay->pitch / 4; +} + +void sdlemuEnableOverlay(void) +{ + showOverlay = 1; +} + +void sdlemuDisableOverlay(void) +{ + showOverlay = 0; +} + +void sdlemu_create_texture(SDL_Surface * src, SDL_Surface * dst, int filter, int src_bpp) +{ + // Local variables. + int w , h; // w and h contain the width and height of the OpenGL texture. + Uint32 rmask, gmask, bmask, amask; // Needed for creating RGBA masks. + int bpp; + + // Delete old texture (if allocated). Useful when there is a screen resize. + if (texture) + SDL_FreeSurface(texture); - rmask = 0x0000; + // Texture width/height should be power of 2 of the SDL_Surface *src when using OpenGL. + // So, find the largest power of two that will contain both the width and height + w = power_of_two(src->w); + h = power_of_two(src->h); + + printf("OpenGL - Texture size : %d x %d\n", w, h); + + // Setting bpp based upon src_bpp. + bpp = src_bpp; + + // We allow the developer to set its own texture bpp. But if the value is NULL or + // not equal to 16, 24 or 32, we make the texturebpp the same as the BPP from src. + if (bpp == 16 || bpp == 24 || bpp == 32) + texturebpp = bpp; + else + texturebpp = src->format->BitsPerPixel; + + printf("OpenGL - Texture depth : %d bpp\n", texturebpp); + + // Now were are going to create a SDL_Surface named texture. This will be our surface + // which will function as a buffer between the SDL_Surface *src and SDL_Surface *dst. + // This buffer is needed because we need to convert the SDL_Surface *src to an OpenGL + // texture with a depth of 16, 24 or 32 bpp, before we can blit the pixels to *dst + // using OpenGL. + // + // NOTE: Seems the byte order here *is* important! + switch (texturebpp) + { + case 16: // *src has depth of 16 bpp +/* + According to information on the SDL mailinglist and on internet, the following + rgba masks should be the ones to use. But somehow the screen gets f*cked up and + the RGB colours are incorrect (at least in Virtual Jaguar/SDL). + + Compile with -DOPENGL_16BPP_CORRECT_RGBA to use this RGBA values. +*/ +#ifdef OPENGL_16BPP_CORRECT_RGBA + rmask = 0x7C00; + gmask = 0x03E0; + bmask = 0x001F; + amask = 0x0000; +#else + rmask = 0x0000; gmask = 0x0000; bmask = 0x0000; amask = 0x0000; - - #endif - break; - case 24: - #if SDL_BYTEORDER == SDL_BIG_ENDIAN - rmask = 0x00ff0000; - gmask = 0x0000ff00; - bmask = 0x000000ff; - amask = 0x00000000; - #else - rmask = 0x000000ff; - gmask = 0x0000ff00; - bmask = 0x00ff0000; - amask = 0x00000000; - #endif - break; - case 32: - default: - #if SDL_BYTEORDER == SDL_BIG_ENDIAN - rmask = 0xff000000; - gmask = 0x00ff0000; - bmask = 0x0000ff00; - amask = 0x000000ff; - #else - rmask = 0x000000ff; - gmask = 0x0000ff00; - bmask = 0x00ff0000; - amask = 0xff000000; - #endif - break; - } - - // create texture surface - texture = SDL_CreateRGBSurface(SDL_SWSURFACE, w, h, texturebpp, rmask, gmask, bmask, amask); -/* - #if SDL_BYTEORDER == SDL_LIL_ENDIAN - 0x000000FF, 0x0000FF00, 0x00FF0000, 0xFF000000); +#endif + break; + case 24: // *src has depth of 24 bpp + #if SDL_BYTEORDER == SDL_BIG_ENDIAN + rmask = 0x00FF0000; + gmask = 0x0000FF00; + bmask = 0x000000FF; + amask = 0x00000000; // IMPORTANT! 24 bpp doesn't use Alpha (at least in our case). #else - 0xFF000000, 0x00FF0000, 0x0000FF00, 0x000000FF); + rmask = 0x000000FF; + gmask = 0x0000FF00; + bmask = 0x00FF0000; + amask = 0x00000000; // IMPORTANT! 24 bpp doesn't use Alpha (at least in our case). #endif -*/ - - -/* - texture = SDL_CreateRGBSurface(SDL_SWSURFACE, w, h, 32, - #if SDL_BYTEORDER == SDL_LIL_ENDIAN - 0x000000FF, 0x0000FF00, 0x00FF0000, 0xFF000000); + break; + case 32: //*src has depth of 32 bpp + default: //which is also the default. + #if SDL_BYTEORDER == SDL_BIG_ENDIAN + rmask = 0xFF000000; + gmask = 0x00FF0000; + bmask = 0x0000FF00; + amask = 0x000000FF; #else - 0xFF000000, 0x00FF0000, 0x0000FF00, 0x000000FF); + rmask = 0x000000FF; + gmask = 0x0000FF00; + bmask = 0x00FF0000; + amask = 0xFF000000; #endif -*/ - // setup 2D gl environment - //glPushAttrib(GL_ENABLE_BIT); - //glDisable(GL_DEPTH_TEST); - //glDisable(GL_CULL_FACE); - //glEnable(GL_TEXTURE_2D); + break; + } + + // Creating SDL_Surface texture based upon the above settings. + texture = SDL_CreateRGBSurface(SDL_SWSURFACE, w, h, texturebpp, rmask, gmask, bmask, amask); + // Setting up OpenGL glDisable(GL_FOG); glDisable(GL_LIGHTING); glDisable(GL_CULL_FACE); glDisable(GL_DEPTH_TEST); - glDisable(GL_BLEND); +// glDisable(GL_BLEND); + glEnable(GL_BLEND); glDisable(GL_NORMALIZE); glDisable(GL_ALPHA_TEST); glEnable(GL_TEXTURE_2D); - glBlendFunc (GL_SRC_ALPHA, GL_ONE); +// glBlendFunc(GL_SRC_ALPHA, GL_ONE); +// glBlendFunc(GL_ONE, GL_SRC_ALPHA); +//This works, but in a wrong way... +// glBlendFunc(GL_ONE, GL_ONE); + // Definitely needed for screen resolution larger then the *src. + // This way we can have automatic scaling functionality. glViewport(0, 0, dst->w, dst->h); - glMatrixMode(GL_PROJECTION); glPushMatrix(); glLoadIdentity(); - glOrtho(0.0, (GLdouble)dst->w, (GLdouble)dst->h, 0.0, 0.0, 1.0); glMatrixMode(GL_MODELVIEW); glPushMatrix(); glLoadIdentity(); - // texture coordinates - texcoord[0] = 0.0f, texcoord[1] = 0.0f, - texcoord[2] = (GLfloat)(src->w) / texture->w, + // Setting up the texture coordinates. + texcoord[0] = 0.0f; + texcoord[1] = 0.0f; + texcoord[2] = (GLfloat)(src->w) / texture->w; texcoord[3] = (GLfloat)(src->h) / texture->h; - // create an RGBA texture for the texture surface + // create a RGB(A) texture for the texture surface glGenTextures(1, &texid); glBindTexture(GL_TEXTURE_2D, texid); - -// if (glFilter) + + // Setting up the OpenGL Filters. These filters are important when we/you + // want to scale the texture. if (filter) { - printf("OpenGL filters: enabled\n"); - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); + // Textures are rendered in best quality. + printf("OpenGL filters: enabled\n"); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); } else { - printf("OpenGL filters: disabled\n"); - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); - } - - switch ( texturebpp ) - { - case 16: - glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB5, texture->w, texture->h, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL); - break; - case 24: - glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, texture->w, texture->h, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL); - break; - case 32: - default: - glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, texture->w, texture->h, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL); - break; - } - - //glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, texture->w, texture->h, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL); + // Textures are rendered in normal quality. + printf("OpenGL filters: disabled\n"); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); + } + + // Setting texture mode. + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP); + + // Generate the texture using the above information. + switch (texturebpp) + { + case 16: + // Normal 16bpp depth based textures consist out of GL_RGB5 and doesn't have support for Alpha channels. + glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB5, texture->w, texture->h, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL); + break; + case 24: + // The 24bpp depth based textures consist out of GL_RGB8 and doesn't have support for Alpha channels. + // + // IMPORTANT : If you don't use Alpha. Use textures with a depth of 16bpp. + // If you use Alpha. Use textures with a depth of 32bpp. + // 24bpp textures are SLOW and avoid them at all costs! + glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, texture->w, texture->h, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL); + break; + case 32: + default: + // The 32bpp depth based textures consist out of GL_RGBA8 and has support for Alpha channels. + glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, texture->w, texture->h, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL); + break; + } }