3 * (C) 2018 by Andreas Eversberg <jolly@eversberg.eu>
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
26 #include "../libsdl/print.h"
28 #define GL3_PROTOTYPES 1
32 static uint8_t *image_rgb = NULL;
33 static uint8_t *osd_rgba[MAX_OSD] = { NULL, NULL };
34 static GLuint image_name;
35 static GLuint osd_name[MAX_OSD];
36 static int image_width, image_height;
37 static int osd_width[MAX_OSD], osd_height[MAX_OSD];
38 static int texture_size;
39 static int osd_size[MAX_OSD];
42 /* alloc and init an image texture with size that is greater than the power of two */
43 int init_opengl_image(int _image_width, int _image_height)
47 image_width = _image_width;
48 image_height = _image_height;
50 /* generate texture */
51 for (texture_size = 1; texture_size <= image_width || texture_size <= image_height; texture_size *= 2)
54 image_rgb = calloc(texture_size * texture_size, 3);
56 print_error("Failed to allocate texture\n");
60 glShadeModel(GL_FLAT);
61 glPixelStorei(GL_UNPACK_ALIGNMENT, 1); /* bytes */
62 glGenTextures(1, &image_name);
63 glBindTexture(GL_TEXTURE_2D, image_name);
64 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
65 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
66 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, texture_size, texture_size, 0, GL_RGB, GL_UNSIGNED_BYTE, image_rgb);
76 /* alloc and init an osd texture with size that is greater than the power of two */
77 int init_opengl_osd(int num, int _osd_width, int _osd_height)
81 if (num < 0 || num >= MAX_OSD) {
82 print_error("given OSD number out of range");
87 osd_width[num] = _osd_width;
88 osd_height[num] = _osd_height;
90 /* generate texture */
91 for (osd_size[num] = 1; osd_size[num] <= osd_width[num] || osd_size[num] <= osd_height[num]; osd_size[num] *= 2)
93 osd_rgba[num] = calloc(osd_size[num] * osd_size[num], 4);
95 print_error("Failed to allocate texture\n");
99 glPixelStorei(GL_UNPACK_ALIGNMENT, 1); /* bytes */
100 glGenTextures(1, &osd_name[num]);
101 glBindTexture(GL_TEXTURE_2D, osd_name[num]);
102 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
103 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
104 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, osd_size[num], osd_size[num], 0, GL_RGBA, GL_UNSIGNED_BYTE, osd_rgba[num]);
113 void opengl_clear(int _flip_y)
118 glClearColor(0.0, 0.0, 0.0, 1.0);
119 glClear(GL_COLOR_BUFFER_BIT);
122 /* set viewport for improved rendering */
123 void opengl_viewport(int view_width, int view_height, int split, int benson_at_line, double fov, double benson_size)
125 int view_x = 0, view_y = 0;
126 double factor_height = 1.0;
127 double factor_width = 1.0;
129 /* center view, or put it in the top half of the window */
131 view_y = view_height / 2;
132 view_height = view_height / 2;
133 } else if (split == 2) {
134 view_height = view_height / 2;
137 /* avoid division by zero, if one dimension is too small */
138 if (view_width < 1 || view_height < 1)
141 /* expand width or height, if apect of image_width:image_height does not match the view_width:view_height */
142 if (view_height * image_width > view_width * image_height)
143 factor_height = (double)(view_height * image_width) / (double)(view_width * image_height);
144 else if (view_height * image_width < view_width * image_height)
145 factor_width = (double)(view_width * image_height) / (double)(view_height * image_width);
147 /* avoid views that are too small */
148 if (view_width < 1 || view_height < 1)
151 /* projection matrix */
152 glViewport((GLsizei)view_x, (GLsizei)view_y, (GLsizei)view_width, (GLsizei)view_height);
153 glMatrixMode(GL_PROJECTION);
156 /* calculate field-of-view */
157 double slope = tan(fov / 360 * M_PI);
158 /* make frustum to center the view in the game view above benson */
159 double left = -slope;
160 double right = slope;
161 double benson_start_at_position = ((double)image_height - (double)benson_at_line) * benson_size;
162 double top = slope * ((double)image_height - benson_start_at_position) / (double)image_width;
163 double bottom = -slope * ((double)image_height * 2.0 - ((double)image_height - benson_start_at_position)) / (double)image_width;
164 glFrustum(left * factor_width, right * factor_width, bottom * factor_height, top * factor_height, 1.0, 5000000000.0);
166 glMatrixMode(GL_MODELVIEW);
169 /* render image or only benson */
170 void opengl_blit_image(uint8_t *rgb, int filter, int benson_at_line, int render_benson_only, double fov, double monitor_distance, double benson_size, int benson_case)
172 double texture_left = 0;
173 double texture_right = ((double)image_width) / (double)texture_size;
174 double texture_top = ((double)benson_at_line) / (double)texture_size;
175 double texture_bottom = ((double)image_height) / (double)texture_size;
176 double image_start_at_position = ((double)image_height - (double)benson_at_line) * benson_size;
177 double image_top = -((double)image_height - image_start_at_position) / (double)image_width;
178 double image_bottom = -((double)image_height * 2.0 - ((double)image_height - image_start_at_position)) / (double)image_width;
180 /* calculate field-of-view */
181 double slope = tan(fov / 360 * M_PI) * monitor_distance;
186 glEnable(GL_CULL_FACE);
191 glEnable(GL_TEXTURE_2D);
192 glBindTexture(GL_TEXTURE_2D, image_name);
193 glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); /* no modulation with color */
194 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, (filter) ? GL_LINEAR : GL_NEAREST);
195 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, (filter) ? GL_LINEAR : GL_NEAREST);
196 if (render_benson_only) {
197 /* render benson only, and copy top line of benson to one line above, so the texture filter will not take false data above benson */
198 rgb += image_width * (benson_at_line - 1) * 3;
199 memcpy(rgb, rgb + image_width * 3, image_width * 3);
200 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, benson_at_line - 1, image_width, image_height - benson_at_line - 1, GL_RGB, GL_UNSIGNED_BYTE, rgb);
202 image_top = -image_top;
204 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, image_width, image_height, GL_RGB, GL_UNSIGNED_BYTE, rgb);
207 glTexCoord2f(texture_left, texture_bottom);
208 glVertex3f(-benson_size * slope, image_bottom * slope, -monitor_distance);
209 glTexCoord2f(texture_right, texture_bottom);
210 glVertex3f(benson_size * slope, image_bottom * slope, -monitor_distance);
211 glTexCoord2f(texture_right, texture_top);
212 glVertex3f(benson_size * slope, image_top * slope, -monitor_distance);
213 glTexCoord2f(texture_left, texture_top);
214 glVertex3f(-benson_size * slope, image_top * slope, -monitor_distance);
216 glDisable(GL_TEXTURE_2D);
217 /* render benson case */
219 double left, right, bottom, top, near, far;
220 left = -benson_size * slope;
221 right = benson_size * slope;
222 bottom = image_bottom * slope;
223 top = image_top * slope;
224 near = -monitor_distance;
225 far = near - benson_size * slope / 3.0;
228 glColor4f(0.3, 0.3, 0.3, 1.0);
229 glVertex3f(left, top, far);
230 glVertex3f(right, top, far);
231 glVertex3f(right, bottom, far);
232 glVertex3f(left, bottom, far);
234 glColor4f(0.2, 0.2, 0.2, 1.0);
235 glVertex3f(left, top, near);
236 glVertex3f(right, top, near);
237 glVertex3f(right, top, far);
238 glVertex3f(left, top, far);
240 glColor4f(0.05, 0.05, 0.05, 1.0);
241 glVertex3f(left, bottom, far);
242 glVertex3f(right, bottom, far);
243 glVertex3f(right, bottom, near);
244 glVertex3f(left, bottom, near);
246 glColor4f(0.1, 0.1, 0.1, 1.0);
247 glVertex3f(left, bottom, far);
248 glVertex3f(left, bottom, near);
249 glVertex3f(left, top, near);
250 glVertex3f(left, top, far);
252 glVertex3f(right, top, far);
253 glVertex3f(right, top, near);
254 glVertex3f(right, bottom, near);
255 glVertex3f(right, bottom, far);
260 glDisable(GL_CULL_FACE);
264 /* render osd texture */
265 void opengl_blit_osd(int num, uint8_t *rgba, int filter, int benson_at_line, double fov, double monitor_distance, double benson_size, double scale_x, double scale_y, double offset_x, double offset_y)
267 double texture_left = 0.0;
268 double texture_right = (double)osd_width[num] / (double)osd_size[num];
269 double texture_top = 0.0;
270 double texture_bottom = (double)osd_height[num] / (double)osd_size[num];
271 double benson_start_at_position;
272 double osd_left = 0.0;
273 double osd_right = 1.0;
274 double osd_top = 0.0;
275 double osd_bottom = 1.0;
276 double slope, range, center;
280 benson_start_at_position = ((double)image_height - (double)benson_at_line) * benson_size;
281 osd_top = ((double)image_height - benson_start_at_position) / (double)image_width;
282 osd_bottom = -((double)image_height * 2.0 - ((double)image_height - benson_start_at_position)) / (double)image_width;
283 /* calculate field-of-view */
284 slope = tan(fov / 360 * M_PI) * monitor_distance;
286 range = (osd_right - osd_left) / 2.0;
287 center = (osd_right + osd_left) / 2.0;
288 osd_left = (osd_left - center) * scale_x + center + range * offset_x;
289 osd_right = (osd_right - center) * scale_x + center + range * offset_x;
290 range = (osd_bottom - osd_top) / 2.0;
291 center = (osd_bottom + osd_top) / 2.0;
292 osd_top = (osd_top - center) * scale_y + center + range * offset_y;
293 osd_bottom = (osd_bottom - center) * scale_y + center + range * offset_y;
296 glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
297 glEnable(GL_TEXTURE_2D);
298 glBindTexture(GL_TEXTURE_2D, osd_name[num]);
299 glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); /* no modulation with color */
300 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, (filter) ? GL_LINEAR : GL_NEAREST);
301 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, (filter) ? GL_LINEAR : GL_NEAREST);
302 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, osd_width[num], osd_height[num], GL_RGBA, GL_UNSIGNED_BYTE, rgba);
305 /* perspective viewport */
306 glTexCoord2f(texture_left, texture_bottom);
307 glVertex3f(osd_left * slope, osd_bottom * slope, -monitor_distance);
308 glTexCoord2f(texture_right, texture_bottom);
309 glVertex3f(osd_right * slope, osd_bottom * slope, -monitor_distance);
310 glTexCoord2f(texture_right, texture_top);
311 glVertex3f(osd_right * slope, osd_top * slope, -monitor_distance);
312 glTexCoord2f(texture_left, texture_top);
313 glVertex3f(osd_left * slope, osd_top * slope, -monitor_distance);
315 /* orthogonal viewport */
316 glTexCoord2f(texture_left, texture_top);
317 glVertex3f(osd_left, osd_top, 0.0);
318 glTexCoord2f(texture_right, texture_top);
319 glVertex3f(osd_right, osd_top, 0.0);
320 glTexCoord2f(texture_right, texture_bottom);
321 glVertex3f(osd_right, osd_bottom, 0.0);
322 glTexCoord2f(texture_left, texture_bottom);
323 glVertex3f(osd_left, osd_bottom, 0.0);
326 glDisable(GL_TEXTURE_2D);
330 /* set color and opacity */
331 void opengl_render_color(double r, double g, double b, double a)
335 glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
336 glColor4d(r, g, b, a);
344 void opengl_render_polygon(double *x, double *y, double *z, int count, int cull_face)
349 glEnable(GL_CULL_FACE);
350 glFrontFace((flip_y) ? GL_CCW : GL_CW);
354 for (i = 0; i < count; i++)
355 glVertex3d(x[i], y[i], -z[i]);
358 glDisable(GL_CULL_FACE);
361 /* render polygon, but make sure any size of it is visible */
362 void opengl_render_polygon_and_line(double *x, double *y, double *z, int count)
367 for (i = 0; i < count; i++)
368 glVertex3d(x[i], y[i], -z[i]);
370 glBegin(GL_LINE_LOOP);
371 for (i = 0; i < count; i++)
372 glVertex3d(x[i], y[i], -z[i]);
377 void opengl_render_line(double x1, double y1, double z1, double x2, double y2, double z2, double size)
381 glVertex3f(x1, y1, -z1);
382 glVertex3f(x2, y2, -z2);
389 void opengl_render_point(double x, double y, double z, double size)
393 glVertex3f(x, y, -z);
399 /* free image texture */
400 void exit_opengl(void)
408 for (i = 0; i < MAX_OSD; i++) {