nkeynes@352: /**
nkeynes@586:  * $Id$
nkeynes@352:  *
nkeynes@352:  * Common GL code that doesn't depend on a specific implementation
nkeynes@352:  *
nkeynes@352:  * Copyright (c) 2005 Nathan Keynes.
nkeynes@352:  *
nkeynes@352:  * This program is free software; you can redistribute it and/or modify
nkeynes@352:  * it under the terms of the GNU General Public License as published by
nkeynes@352:  * the Free Software Foundation; either version 2 of the License, or
nkeynes@352:  * (at your option) any later version.
nkeynes@352:  *
nkeynes@352:  * This program is distributed in the hope that it will be useful,
nkeynes@352:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
nkeynes@352:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
nkeynes@352:  * GNU General Public License for more details.
nkeynes@352:  */
nkeynes@352: 
nkeynes@443: #include <sys/time.h>
nkeynes@443: 
nkeynes@540: #include "display.h"
nkeynes@481: #include "pvr2/pvr2.h"
nkeynes@352: #include "drivers/gl_common.h"
nkeynes@352: 
nkeynes@352: extern uint32_t video_width, video_height;
nkeynes@352: 
nkeynes@352: char *required_extensions[] = { "GL_EXT_framebuffer_object", NULL };
nkeynes@352: 
nkeynes@352: /**
nkeynes@352:  * Test if a specific extension is supported. From opengl.org
nkeynes@352:  * @param extension extension name to check for
nkeynes@352:  * @return TRUE if supported, otherwise FALSE.
nkeynes@352:  */
nkeynes@352: gboolean isGLExtensionSupported( const char *extension )
nkeynes@352: {
nkeynes@352:     const GLubyte *extensions = NULL;
nkeynes@352:     const GLubyte *start;
nkeynes@352:     GLubyte *where, *terminator;
nkeynes@352: 
nkeynes@352:     /* Extension names should not have spaces. */
nkeynes@352:     where = (GLubyte *) strchr(extension, ' ');
nkeynes@352:     if (where || *extension == '\0')
nkeynes@352: 	return 0;
nkeynes@352:     extensions = glGetString(GL_EXTENSIONS);
nkeynes@352:     /* It takes a bit of care to be fool-proof about parsing the
nkeynes@352:        OpenGL extensions string. Don't be fooled by sub-strings,
nkeynes@352:        etc. */
nkeynes@352:     start = extensions;
nkeynes@352:     for (;;) {
nkeynes@352: 	where = (GLubyte *) strstr((const char *) start, extension);
nkeynes@352: 	if (!where)
nkeynes@352: 	    break;
nkeynes@352: 	terminator = where + strlen(extension);
nkeynes@352: 	if (where == start || *(where - 1) == ' ')
nkeynes@352: 	    if (*terminator == ' ' || *terminator == '\0')
nkeynes@352: 		return TRUE;
nkeynes@352: 	start = terminator;
nkeynes@352:     }
nkeynes@352:     return FALSE;
nkeynes@352: }
nkeynes@352: 
nkeynes@352: gboolean hasRequiredGLExtensions( ) 
nkeynes@352: {
nkeynes@352:     int i;
nkeynes@352:     gboolean isOK = TRUE;
nkeynes@352: 
nkeynes@352:     for( i=0; required_extensions[i] != NULL; i++ ) {
nkeynes@352: 	if( !isGLExtensionSupported(required_extensions[i]) ) {
nkeynes@352: 	    ERROR( "Required OpenGL extension not supported: %s", required_extensions[i] );
nkeynes@352: 	    isOK = FALSE;
nkeynes@352: 	}
nkeynes@352:     }
nkeynes@352:     return isOK;
nkeynes@352: }
nkeynes@352: 
nkeynes@545: /**
nkeynes@545:  * Reset the gl state to simple orthographic projection with 
nkeynes@545:  * texturing, alpha/depth/scissor/cull tests disabled.
nkeynes@545:  */
nkeynes@545: void gl_reset_state()
nkeynes@443: {
nkeynes@352:     glViewport( 0, 0, video_width, video_height );
nkeynes@352:     glMatrixMode(GL_PROJECTION);
nkeynes@352:     glLoadIdentity();
nkeynes@352:     glOrtho( 0, video_width, video_height, 0, 0, -65535 );
nkeynes@352:     glMatrixMode(GL_MODELVIEW);
nkeynes@352:     glLoadIdentity();
nkeynes@352:     glDisable( GL_TEXTURE_2D );
nkeynes@352:     glDisable( GL_ALPHA_TEST );
nkeynes@352:     glDisable( GL_DEPTH_TEST );
nkeynes@352:     glDisable( GL_SCISSOR_TEST );
nkeynes@352:     glDisable( GL_CULL_FACE );
nkeynes@545:     glDrawBuffer( GL_FRONT );
nkeynes@545: }
nkeynes@545: 
nkeynes@545: void gl_display_render_buffer( render_buffer_t buffer )
nkeynes@545: {
nkeynes@545:     gl_texture_window( buffer->width, buffer->height, buffer->buf_id, buffer->inverted );
nkeynes@545: }
nkeynes@545: 
nkeynes@545: void gl_texture_window( int width, int height, int tex_id, gboolean inverted )
nkeynes@545: {
nkeynes@545:     float top, bottom;
nkeynes@545:     if( inverted ) {
nkeynes@586: 	top = ((float)height);
nkeynes@586: 	bottom = 0;
nkeynes@545:     } else {
nkeynes@586: 	top = 0;
nkeynes@586: 	bottom = ((float)height);
nkeynes@545:     }
nkeynes@545: 
nkeynes@545:     /* Reset display parameters */
nkeynes@545:     gl_reset_state();
nkeynes@545:     glColor3f( 0,0,0 );    
nkeynes@444: 
nkeynes@444:     int x1=0,y1=0,x2=video_width,y2=video_height;
nkeynes@444: 
nkeynes@444:     int ah = video_width * 0.75;
nkeynes@444: 
nkeynes@444:     if( ah > video_height ) {
nkeynes@444: 	int w = (video_height/0.75);
nkeynes@444: 	x1 = (video_width - w)/2;
nkeynes@444: 	x2 -= x1;
nkeynes@444: 
nkeynes@444: 	glBegin( GL_QUADS );
nkeynes@444: 	glVertex2f( 0, 0 );
nkeynes@444: 	glVertex2f( x1, 0 );
nkeynes@444: 	glVertex2f( x1, video_height );
nkeynes@444: 	glVertex2f( 0, video_height);
nkeynes@444: 	glVertex2f( x2, 0 );
nkeynes@444: 	glVertex2f( video_width, 0 );
nkeynes@444: 	glVertex2f( video_width, video_height );
nkeynes@444: 	glVertex2f( x2, video_height);
nkeynes@444: 	glEnd();
nkeynes@444:     } else if( ah < video_height ) {
nkeynes@444: 	y1 = (video_height - ah)/2;
nkeynes@444: 	y2 -= y1;
nkeynes@444: 	glBegin( GL_QUADS );
nkeynes@444: 	glVertex2f( 0, 0 );
nkeynes@444: 	glVertex2f( video_width, 0 );
nkeynes@444: 	glVertex2f( video_width, y1 );
nkeynes@444: 	glVertex2f( 0, y1 );
nkeynes@444: 	glVertex2f( 0, y2 );
nkeynes@444: 	glVertex2f( video_width, y2 );
nkeynes@444: 	glVertex2f( video_width, video_height );
nkeynes@444: 	glVertex2f( 0, video_height );
nkeynes@444: 	glEnd();
nkeynes@444:     }
nkeynes@352: 
nkeynes@443:     /* Render the textured rectangle */
nkeynes@443:     glEnable( GL_TEXTURE_RECTANGLE_ARB );
nkeynes@545:     glBindTexture( GL_TEXTURE_RECTANGLE_ARB, tex_id );
nkeynes@443:     glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE );
nkeynes@443:     glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
nkeynes@443:     glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
nkeynes@443:     glEnable( GL_BLEND );
nkeynes@443:     glBlendFunc( GL_ONE, GL_ZERO );
nkeynes@352:     glBegin( GL_QUADS );
nkeynes@586:     glTexCoord2f( 0, top );
nkeynes@444:     glVertex2f( x1, y1 );
nkeynes@586:     glTexCoord2f( ((float)width), top );
nkeynes@444:     glVertex2f( x2, y1 );
nkeynes@586:     glTexCoord2f( ((float)width), bottom );
nkeynes@444:     glVertex2f( x2, y2 );
nkeynes@586:     glTexCoord2f( 0, bottom );
nkeynes@444:     glVertex2f( x1, y2 );
nkeynes@352:     glEnd();
nkeynes@443:     glDisable( GL_TEXTURE_RECTANGLE_ARB );
nkeynes@352:     glFlush();
nkeynes@443: }
nkeynes@443: 
nkeynes@545: gboolean gl_load_frame_buffer( frame_buffer_t frame, int tex_id )
nkeynes@443: {
nkeynes@477:     GLenum type = colour_formats[frame->colour_format].type;
nkeynes@477:     GLenum format = colour_formats[frame->colour_format].format;
nkeynes@477:     int bpp = colour_formats[frame->colour_format].bpp;
nkeynes@477:     int rowstride = (frame->rowstride / bpp) - frame->width;
nkeynes@477:     
nkeynes@477:     glPixelStorei( GL_UNPACK_ROW_LENGTH, rowstride );
nkeynes@545:     glBindTexture( GL_TEXTURE_RECTANGLE_ARB, tex_id );
nkeynes@477:     glTexSubImage2D( GL_TEXTURE_RECTANGLE_ARB, 0, 0,0,
nkeynes@481: 		     frame->width, frame->height, format, type, frame->data );
nkeynes@481:     return TRUE;
nkeynes@352: }
nkeynes@352: 
nkeynes@352: gboolean gl_display_blank( uint32_t colour )
nkeynes@352: {
nkeynes@545:     gl_reset_state();
nkeynes@545:     glColor3ub( (colour >> 16) & 0xFF, (colour >> 8) & 0xFF, colour & 0xFF );
nkeynes@352:     glRecti(0,0, video_width, video_height );
nkeynes@352:     glFlush();
nkeynes@352:     return TRUE;
nkeynes@352: }
nkeynes@352: 
nkeynes@352: /**
nkeynes@352:  * Generic GL read_render_buffer. This function assumes that the caller
nkeynes@352:  * has already set the appropriate glReadBuffer(); in other words, unless
nkeynes@352:  * there's only one buffer this needs to be wrapped.
nkeynes@352:  */
nkeynes@477: gboolean gl_read_render_buffer( unsigned char *target, render_buffer_t buffer, 
nkeynes@477: 				int rowstride, int colour_format ) 
nkeynes@352: {
nkeynes@352:     glFinish();
nkeynes@477:     GLenum type = colour_formats[colour_format].type;
nkeynes@477:     GLenum format = colour_formats[colour_format].format;
nkeynes@477:     // int line_size = buffer->width * colour_formats[colour_format].bpp;
nkeynes@424:     // int size = line_size * buffer->height;
nkeynes@477:     int glrowstride = (rowstride / colour_formats[colour_format].bpp) - buffer->width;
nkeynes@477:     glPixelStorei( GL_PACK_ROW_LENGTH, glrowstride );
nkeynes@352:     
nkeynes@352:     glReadPixels( 0, 0, buffer->width, buffer->height, format, type, target );
nkeynes@352:     return TRUE;
nkeynes@352: }