4 * Common GL code that doesn't depend on a specific implementation
6 * Copyright (c) 2005 Nathan Keynes.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
22 #include "pvr2/pvr2.h"
23 #include "drivers/video_gl.h"
25 extern uint32_t video_width, video_height;
28 * Reset the gl state to simple orthographic projection with
29 * texturing, alpha/depth/scissor/cull tests disabled.
33 glViewport( 0, 0, video_width, video_height );
34 glMatrixMode(GL_PROJECTION);
36 glOrtho( 0, video_width, video_height, 0, 0, 65535 );
37 glMatrixMode(GL_MODELVIEW);
40 glDisable( GL_TEXTURE_2D );
41 glDisable( GL_TEXTURE_RECTANGLE_ARB );
42 glDisable( GL_ALPHA_TEST );
43 glDisable( GL_DEPTH_TEST );
44 glDisable( GL_SCISSOR_TEST );
45 glDisable( GL_CULL_FACE );
46 glDrawBuffer( GL_FRONT );
49 void gl_display_render_buffer( render_buffer_t buffer )
51 gl_texture_window( buffer->width, buffer->height, buffer->buf_id, buffer->inverted );
55 * Convert window coordinates to dreamcast device coords (640x480) using the
56 * same viewable area as gl_texture_window.
57 * If the coordinates are outside the viewable area, the result is -1,-1.
59 void gl_window_to_system_coords( int *x, int *y )
61 int x1=0,y1=0,x2=video_width,y2=video_height;
63 int ah = video_width * 0.75;
65 if( ah > video_height ) {
66 int w = (video_height/0.75);
67 x1 = (video_width - w)/2;
69 } else if( ah < video_height ) {
70 y1 = (video_height - ah)/2;
73 if( *x < x1 || *x >= x2 || *y < y1 || *y >= y2 ) {
77 *x = (*x - x1) * DISPLAY_WIDTH / (x2-x1);
78 *y = (*y - y1) * DISPLAY_HEIGHT / (y2-y1);
82 void gl_texture_window( int width, int height, int tex_id, gboolean inverted )
86 top = ((float)height);
90 bottom = ((float)height);
93 /* Reset display parameters */
97 int x1=0,y1=0,x2=video_width,y2=video_height;
99 int ah = video_width * 0.75;
101 if( ah > video_height ) {
102 int w = (video_height/0.75);
103 x1 = (video_width - w)/2;
109 glVertex2f( x1, video_height );
110 glVertex2f( 0, video_height);
112 glVertex2f( video_width, 0 );
113 glVertex2f( video_width, video_height );
114 glVertex2f( x2, video_height);
116 } else if( ah < video_height ) {
117 y1 = (video_height - ah)/2;
121 glVertex2f( video_width, 0 );
122 glVertex2f( video_width, y1 );
125 glVertex2f( video_width, y2 );
126 glVertex2f( video_width, video_height );
127 glVertex2f( 0, video_height );
131 /* Render the textured rectangle */
132 glEnable( GL_TEXTURE_RECTANGLE_ARB );
133 glBindTexture( GL_TEXTURE_RECTANGLE_ARB, tex_id );
134 glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE );
135 glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
136 glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
137 glEnable( GL_BLEND );
138 glBlendFunc( GL_ONE, GL_ZERO );
140 glTexCoord2f( 0, top );
141 glVertex2f( x1, y1 );
142 glTexCoord2f( ((float)width), top );
143 glVertex2f( x2, y1 );
144 glTexCoord2f( ((float)width), bottom );
145 glVertex2f( x2, y2 );
146 glTexCoord2f( 0, bottom );
147 glVertex2f( x1, y2 );
149 glDisable( GL_TEXTURE_RECTANGLE_ARB );
153 gboolean gl_load_frame_buffer( frame_buffer_t frame, int tex_id )
155 GLenum type = colour_formats[frame->colour_format].type;
156 GLenum format = colour_formats[frame->colour_format].format;
157 int bpp = colour_formats[frame->colour_format].bpp;
158 int rowstride = (frame->rowstride / bpp) - frame->width;
160 glPixelStorei( GL_UNPACK_ROW_LENGTH, rowstride );
161 glBindTexture( GL_TEXTURE_RECTANGLE_ARB, tex_id );
162 glTexSubImage2D( GL_TEXTURE_RECTANGLE_ARB, 0, 0,0,
163 frame->width, frame->height, format, type, frame->data );
167 void gl_display_blank( uint32_t colour )
170 glColor3ub( (colour >> 16) & 0xFF, (colour >> 8) & 0xFF, colour & 0xFF );
171 glRecti(0,0, video_width, video_height );
176 * Generic GL read_render_buffer. This function assumes that the caller
177 * has already set the appropriate glReadBuffer(); in other words, unless
178 * there's only one buffer this needs to be wrapped.
180 gboolean gl_read_render_buffer( unsigned char *target, render_buffer_t buffer,
181 int rowstride, int colour_format )
184 GLenum type = colour_formats[colour_format].type;
185 GLenum format = colour_formats[colour_format].format;
186 // int line_size = buffer->width * colour_formats[colour_format].bpp;
187 // int size = line_size * buffer->height;
188 int glrowstride = (rowstride / colour_formats[colour_format].bpp) - buffer->width;
189 glPixelStorei( GL_PACK_ROW_LENGTH, glrowstride );
191 glReadPixels( 0, 0, buffer->width, buffer->height, format, type, target );
.