oculus2
view src/main.c @ 6:37c753411934
added a comment listing the GLEW dependency and adding dep urls
| author | John Tsiombikas <nuclear@member.fsf.org> |
|---|---|
| date | Fri, 05 Sep 2014 03:23:19 +0300 |
| parents | cd9f1560b909 |
| children | 5b04743fd3d0 |
line source
1 /* Very simple OculusSDK OpenGL usage example.
2 *
3 * Uses SDL2 (www.libsdl.org) for event handling and OpenGL context management.
4 * Uses GLEW (glew.sourceforge.net) for OpenGL extension wrangling.
5 *
6 * Author: John Tsiombikas <nuclear@member.fsf.org>
7 * This code is in the public domain. Do whatever you like with it.
8 */
9 #include <stdio.h>
10 #include <stdlib.h>
11 #include <assert.h>
12 #include <SDL2/SDL.h>
13 #include <GL/glew.h>
15 #ifdef WIN32
16 #define OVR_OS_WIN32
17 #endif
18 #ifdef __APPLE__
19 #define OVR_OS_MAC
20 #endif
22 #include <OVR_CAPI.h>
23 #include <OVR_CAPI_GL.h>
25 int init(void);
26 void cleanup(void);
27 void toggle_hmd_fullscreen(void);
28 void display(void);
29 void draw_scene(void);
30 void draw_box(float xsz, float ysz, float zsz, float norm_sign);
31 void update_rtarg(int width, int height);
32 int handle_event(SDL_Event *ev);
33 int key_event(int key, int state);
34 void reshape(int x, int y);
35 unsigned int next_pow2(unsigned int x);
36 void quat_to_matrix(const float *quat, float *mat);
37 unsigned int gen_chess_tex(float r0, float g0, float b0, float r1, float g1, float b1);
39 /* forward declaration to avoid including non-public headers of libovr */
40 OVR_EXPORT void ovrhmd_EnableHSWDisplaySDKRender(ovrHmd hmd, ovrBool enable);
42 static SDL_Window *win;
43 static SDL_GLContext ctx;
44 static int win_width, win_height;
46 static unsigned int fbo, fb_tex, fb_depth;
47 static int fb_width, fb_height;
48 static int fb_tex_width, fb_tex_height;
50 static ovrHmd hmd;
51 static ovrSizei eyeres[2];
52 static ovrEyeRenderDesc eye_rdesc[2];
53 static ovrGLTexture fb_ovr_tex[2];
55 static unsigned int chess_tex;
58 int main(int argc, char **argv)
59 {
60 if(init() == -1) {
61 return 1;
62 }
64 for(;;) {
65 SDL_Event ev;
66 while(SDL_PollEvent(&ev)) {
67 if(handle_event(&ev) == -1) {
68 goto done;
69 }
70 }
71 display();
72 }
74 done:
75 cleanup();
76 return 0;
77 }
80 int init(void)
81 {
82 int i, x, y;
83 unsigned int flags, dcaps;
84 union ovrGLConfig glcfg;
86 /* libovr must be initialized before we create the OpenGL context */
87 ovr_Initialize();
89 SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER);
91 x = y = SDL_WINDOWPOS_UNDEFINED;
92 flags = SDL_WINDOW_OPENGL;
93 if(!(win = SDL_CreateWindow("press 'f' to move to the HMD", x, y, 1280, 800, flags))) {
94 fprintf(stderr, "failed to create window\n");
95 return -1;
96 }
97 if(!(ctx = SDL_GL_CreateContext(win))) {
98 fprintf(stderr, "failed to create OpenGL context\n");
99 return -1;
100 }
102 glewInit();
104 if(!(hmd = ovrHmd_Create(0))) {
105 fprintf(stderr, "failed to open Oculus HMD, falling back to virtual debug HMD\n");
106 if(!(hmd = ovrHmd_CreateDebug(ovrHmd_DK2))) {
107 fprintf(stderr, "failed to create virtual debug HMD\n");
108 return -1;
109 }
110 }
111 printf("initialized HMD: %s - %s\n", hmd->Manufacturer, hmd->ProductName);
113 /* resize our window to match the HMD resolution */
114 SDL_SetWindowSize(win, hmd->Resolution.w, hmd->Resolution.h);
115 SDL_SetWindowPosition(win, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED);
116 win_width = hmd->Resolution.w;
117 win_height = hmd->Resolution.h;
119 /* enable position and rotation tracking (and anything else they might add in the future) */
120 ovrHmd_ConfigureTracking(hmd, 0xffffffff, 0);
121 /* retrieve the optimal render target resolution for each eye */
122 eyeres[0] = ovrHmd_GetFovTextureSize(hmd, ovrEye_Left, hmd->DefaultEyeFov[0], 1.0);
123 eyeres[1] = ovrHmd_GetFovTextureSize(hmd, ovrEye_Right, hmd->DefaultEyeFov[1], 1.0);
125 /* and create a single render target texture to encompass both eyes */
126 fb_width = eyeres[0].w + eyeres[1].w;
127 fb_height = eyeres[0].h > eyeres[1].h ? eyeres[0].h : eyeres[1].h;
128 update_rtarg(fb_width, fb_height);
130 /* fill in the ovrGLTexture structures that describe our render target texture */
131 for(i=0; i<2; i++) {
132 fb_ovr_tex[i].OGL.Header.API = ovrRenderAPI_OpenGL;
133 fb_ovr_tex[i].OGL.Header.TextureSize.w = fb_tex_width;
134 fb_ovr_tex[i].OGL.Header.TextureSize.h = fb_tex_height;
135 /* this next field is the only one that differs between the two eyes */
136 fb_ovr_tex[i].OGL.Header.RenderViewport.Pos.x = i == 0 ? 0 : fb_width / 2.0;
137 fb_ovr_tex[i].OGL.Header.RenderViewport.Pos.y = fb_tex_height - fb_height;
138 fb_ovr_tex[i].OGL.Header.RenderViewport.Size.w = fb_width / 2.0;
139 fb_ovr_tex[i].OGL.Header.RenderViewport.Size.h = fb_height;
140 fb_ovr_tex[i].OGL.TexId = fb_tex; /* both eyes will use the same texture id */
141 }
143 /* fill in the ovrGLConfig structure needed by the SDK to draw our stereo pair
144 * to the actual HMD display (SDK-distortion mode)
145 */
146 memset(&glcfg, 0, sizeof glcfg);
147 glcfg.OGL.Header.API = ovrRenderAPI_OpenGL;
148 glcfg.OGL.Header.RTSize = hmd->Resolution;
149 glcfg.OGL.Header.Multisample = 1;
151 if(hmd->HmdCaps & ovrHmdCap_ExtendDesktop) {
152 printf("running in \"extended desktop\" mode\n");
153 } else {
154 /* to sucessfully draw to the HMD display in "direct-hmd" mode, we have to
155 * call ovrHmd_AttachToWindow
156 * XXX: this doesn't work properly yet due to bugs in the oculus 0.4.1 sdk/driver
157 */
158 #ifdef WIN32
159 void *sys_win = GetActiveWindow();
160 glcfg.OGL.Window = sys_win;
161 glcfg.OGL.DC = wglGetCurrentDC();
162 ovrHmd_AttachToWindow(hmd, sys_win, 0, 0);
163 #endif
164 printf("running in \"direct-hmd\" mode\n");
165 }
167 /* enable low-persistence display and dynamic prediction for lattency compensation */
168 ovrHmd_SetEnabledCaps(hmd, ovrHmdCap_LowPersistence | ovrHmdCap_DynamicPrediction);
170 /* configure SDK-rendering and enable chromatic abberation correction, vignetting, and
171 * timewrap, which shifts the image before drawing to counter any lattency between the call
172 * to ovrHmd_GetEyePose and ovrHmd_EndFrame.
173 */
174 dcaps = ovrDistortionCap_Chromatic | ovrDistortionCap_Vignette | ovrDistortionCap_TimeWarp;
175 if(!ovrHmd_ConfigureRendering(hmd, &glcfg.Config, dcaps, hmd->DefaultEyeFov, eye_rdesc)) {
176 fprintf(stderr, "failed to configure distortion renderer\n");
177 }
179 /* disable the retarded "health and safety warning" */
180 ovrhmd_EnableHSWDisplaySDKRender(hmd, 0);
182 glEnable(GL_DEPTH_TEST);
183 glEnable(GL_CULL_FACE);
184 glEnable(GL_LIGHTING);
185 glEnable(GL_LIGHT0);
186 glEnable(GL_LIGHT1);
187 glEnable(GL_NORMALIZE);
189 glClearColor(0.1, 0.1, 0.1, 1);
191 chess_tex = gen_chess_tex(1.0, 0.7, 0.4, 0.4, 0.7, 1.0);
192 return 0;
193 }
195 void cleanup(void)
196 {
197 if(hmd) {
198 ovrHmd_Destroy(hmd);
199 }
200 ovr_Shutdown();
202 SDL_Quit();
203 }
205 void toggle_hmd_fullscreen(void)
206 {
207 static int fullscr, prev_x, prev_y;
208 fullscr = !fullscr;
210 if(fullscr) {
211 /* going fullscreen on the rift. save current window position, and move it
212 * to the rift's part of the desktop before going fullscreen
213 */
214 SDL_GetWindowPosition(win, &prev_x, &prev_y);
215 SDL_SetWindowPosition(win, hmd->WindowsPos.x, hmd->WindowsPos.y);
216 SDL_SetWindowFullscreen(win, SDL_WINDOW_FULLSCREEN_DESKTOP);
217 } else {
218 /* return to windowed mode and move the window back to its original position */
219 SDL_SetWindowFullscreen(win, 0);
220 SDL_SetWindowPosition(win, prev_x, prev_y);
221 }
222 }
224 void display(void)
225 {
226 int i;
227 ovrMatrix4f proj;
228 ovrPosef pose[2];
229 float rot_mat[16];
231 /* the drawing starts with a call to ovrHmd_BeginFrame */
232 ovrHmd_BeginFrame(hmd, 0);
234 /* start drawing onto our texture render target */
235 glBindFramebuffer(GL_FRAMEBUFFER, fbo);
236 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
238 /* for each eye ... */
239 for(i=0; i<2; i++) {
240 int eye = hmd->EyeRenderOrder[i];
242 /* -- viewport transformation --
243 * setup the viewport to draw in the left half of the framebuffer when we're
244 * rendering the left eye's view (0, 0, width/2, height), and in the right half
245 * of the framebuffer for the right eye's view (width/2, 0, width/2, height)
246 */
247 glViewport(eye == 0 ? 0 : fb_width / 2, 0, fb_width / 2, fb_height);
249 /* -- projection transformation --
250 * we'll just have to use the projection matrix supplied by the oculus SDK for this eye
251 * note that libovr matrices are the transpose of what OpenGL expects, so we have to
252 * use glLoadTransposeMatrixf instead of glLoadMatrixf to load it.
253 */
254 proj = ovrMatrix4f_Projection(hmd->DefaultEyeFov[eye], 0.5, 500.0, 1);
255 glMatrixMode(GL_PROJECTION);
256 glLoadTransposeMatrixf(proj.M[0]);
258 /* -- view/camera transformation --
259 * we need to construct a view matrix by combining all the information provided by the oculus
260 * SDK, about the position and orientation of the user's head in the world.
261 */
262 pose[eye] = ovrHmd_GetEyePose(hmd, eye);
263 glMatrixMode(GL_MODELVIEW);
264 glLoadIdentity();
265 glTranslatef(eye_rdesc[eye].ViewAdjust.x, eye_rdesc[eye].ViewAdjust.y, eye_rdesc[eye].ViewAdjust.z);
266 /* retrieve the orientation quaternion and convert it to a rotation matrix */
267 quat_to_matrix(&pose[eye].Orientation.x, rot_mat);
268 glMultMatrixf(rot_mat);
269 /* translate the view matrix with the positional tracking */
270 glTranslatef(-pose[eye].Position.x, -pose[eye].Position.y, -pose[eye].Position.z);
271 /* move the camera to the eye level of the user */
272 glTranslatef(0, -ovrHmd_GetFloat(hmd, OVR_KEY_EYE_HEIGHT, 1.65), 0);
274 /* finally draw the scene for this eye */
275 draw_scene();
276 }
278 /* after drawing both eyes into the texture render target, revert to drawing directly to the
279 * display, and we call ovrHmd_EndFrame, to let the Oculus SDK draw both images properly
280 * compensated for lens distortion and chromatic abberation onto the HMD screen.
281 */
282 glBindFramebuffer(GL_FRAMEBUFFER, 0);
283 glViewport(0, 0, win_width, win_height);
285 ovrHmd_EndFrame(hmd, pose, &fb_ovr_tex[0].Texture);
287 assert(glGetError() == GL_NO_ERROR);
288 }
290 void draw_scene(void)
291 {
292 int i;
293 float grey[] = {0.8, 0.8, 0.8, 1};
294 float col[] = {0, 0, 0, 1};
295 float lpos[][4] = {
296 {-8, 2, 10, 1},
297 {0, 15, 0, 1}
298 };
299 float lcol[][4] = {
300 {0.8, 0.8, 0.8, 1},
301 {0.4, 0.3, 0.3, 1}
302 };
304 for(i=0; i<2; i++) {
305 glLightfv(GL_LIGHT0 + i, GL_POSITION, lpos[i]);
306 glLightfv(GL_LIGHT0 + i, GL_DIFFUSE, lcol[i]);
307 }
309 glMatrixMode(GL_MODELVIEW);
311 glPushMatrix();
312 glTranslatef(0, 10, 0);
313 glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, grey);
314 glBindTexture(GL_TEXTURE_2D, chess_tex);
315 glEnable(GL_TEXTURE_2D);
316 draw_box(30, 20, 30, -1.0);
317 glDisable(GL_TEXTURE_2D);
318 glPopMatrix();
320 for(i=0; i<4; i++) {
321 glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, grey);
322 glPushMatrix();
323 glTranslatef(i & 1 ? 5 : -5, 1, i & 2 ? -5 : 5);
324 draw_box(0.5, 2, 0.5, 1.0);
325 glPopMatrix();
327 col[0] = i & 1 ? 1.0 : 0.3;
328 col[1] = i == 0 ? 1.0 : 0.3;
329 col[2] = i & 2 ? 1.0 : 0.3;
330 glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, col);
332 glPushMatrix();
333 if(i & 1) {
334 glTranslatef(0, 0.25, i & 2 ? 2 : -2);
335 } else {
336 glTranslatef(i & 2 ? 2 : -2, 0.25, 0);
337 }
338 draw_box(0.5, 0.5, 0.5, 1.0);
339 glPopMatrix();
340 }
341 }
343 void draw_box(float xsz, float ysz, float zsz, float norm_sign)
344 {
345 glMatrixMode(GL_MODELVIEW);
346 glScalef(xsz * 0.5, ysz * 0.5, zsz * 0.5);
348 if(norm_sign < 0.0) {
349 glFrontFace(GL_CW);
350 }
352 glBegin(GL_QUADS);
353 glNormal3f(0, 0, 1 * norm_sign);
354 glTexCoord2f(0, 0); glVertex3f(-1, -1, 1);
355 glTexCoord2f(1, 0); glVertex3f(1, -1, 1);
356 glTexCoord2f(1, 1); glVertex3f(1, 1, 1);
357 glTexCoord2f(0, 1); glVertex3f(-1, 1, 1);
358 glNormal3f(1 * norm_sign, 0, 0);
359 glTexCoord2f(0, 0); glVertex3f(1, -1, 1);
360 glTexCoord2f(1, 0); glVertex3f(1, -1, -1);
361 glTexCoord2f(1, 1); glVertex3f(1, 1, -1);
362 glTexCoord2f(0, 1); glVertex3f(1, 1, 1);
363 glNormal3f(0, 0, -1 * norm_sign);
364 glTexCoord2f(0, 0); glVertex3f(1, -1, -1);
365 glTexCoord2f(1, 0); glVertex3f(-1, -1, -1);
366 glTexCoord2f(1, 1); glVertex3f(-1, 1, -1);
367 glTexCoord2f(0, 1); glVertex3f(1, 1, -1);
368 glNormal3f(-1 * norm_sign, 0, 0);
369 glTexCoord2f(0, 0); glVertex3f(-1, -1, -1);
370 glTexCoord2f(1, 0); glVertex3f(-1, -1, 1);
371 glTexCoord2f(1, 1); glVertex3f(-1, 1, 1);
372 glTexCoord2f(0, 1); glVertex3f(-1, 1, -1);
373 glEnd();
374 glBegin(GL_TRIANGLE_FAN);
375 glNormal3f(0, 1 * norm_sign, 0);
376 glTexCoord2f(0.5, 0.5); glVertex3f(0, 1, 0);
377 glTexCoord2f(0, 0); glVertex3f(-1, 1, 1);
378 glTexCoord2f(1, 0); glVertex3f(1, 1, 1);
379 glTexCoord2f(1, 1); glVertex3f(1, 1, -1);
380 glTexCoord2f(0, 1); glVertex3f(-1, 1, -1);
381 glTexCoord2f(0, 0); glVertex3f(-1, 1, 1);
382 glEnd();
383 glBegin(GL_TRIANGLE_FAN);
384 glNormal3f(0, -1 * norm_sign, 0);
385 glTexCoord2f(0.5, 0.5); glVertex3f(0, -1, 0);
386 glTexCoord2f(0, 0); glVertex3f(-1, -1, -1);
387 glTexCoord2f(1, 0); glVertex3f(1, -1, -1);
388 glTexCoord2f(1, 1); glVertex3f(1, -1, 1);
389 glTexCoord2f(0, 1); glVertex3f(-1, -1, 1);
390 glTexCoord2f(0, 0); glVertex3f(-1, -1, -1);
391 glEnd();
393 glFrontFace(GL_CCW);
394 }
396 /* update_rtarg creates (and/or resizes) the render target used to draw the two stero views */
397 void update_rtarg(int width, int height)
398 {
399 if(!fbo) {
400 /* if fbo does not exist, then nothing does... create every opengl object */
401 glGenFramebuffers(1, &fbo);
402 glGenTextures(1, &fb_tex);
403 glGenRenderbuffers(1, &fb_depth);
405 glBindTexture(GL_TEXTURE_2D, fb_tex);
406 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
407 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
408 }
410 glBindFramebuffer(GL_FRAMEBUFFER, fbo);
412 /* calculate the next power of two in both dimensions and use that as a texture size */
413 fb_tex_width = next_pow2(width);
414 fb_tex_height = next_pow2(height);
416 /* create and attach the texture that will be used as a color buffer */
417 glBindTexture(GL_TEXTURE_2D, fb_tex);
418 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, fb_tex_width, fb_tex_height, 0,
419 GL_RGBA, GL_UNSIGNED_BYTE, 0);
420 glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, fb_tex, 0);
422 /* create and attach the renderbuffer that will serve as our z-buffer */
423 glBindRenderbuffer(GL_RENDERBUFFER, fb_depth);
424 glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, fb_tex_width, fb_tex_height);
425 glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, fb_depth);
427 if(glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
428 fprintf(stderr, "incomplete framebuffer!\n");
429 }
431 glBindFramebuffer(GL_FRAMEBUFFER, 0);
432 printf("created render target: %dx%d (texture size: %dx%d)\n", width, height, fb_tex_width, fb_tex_height);
433 }
435 int handle_event(SDL_Event *ev)
436 {
437 switch(ev->type) {
438 case SDL_QUIT:
439 return -1;
441 case SDL_KEYDOWN:
442 case SDL_KEYUP:
443 if(key_event(ev->key.keysym.sym, ev->key.state == SDL_PRESSED) == -1) {
444 return -1;
445 }
446 break;
448 default:
449 break;
450 }
452 return 0;
453 }
455 int key_event(int key, int state)
456 {
457 if(state) {
458 /*
459 ovrHSWDisplayState hsw;
460 ovrHmd_GetHSWDisplayState(hmd, &hsw);
461 if(hsw.Displayed) {
462 ovrHmd_DismissHSWDisplay(hmd);
463 }
464 */
466 switch(key) {
467 case 27:
468 return -1;
470 case ' ':
471 /* allow the user to recenter by pressing space */
472 ovrHmd_RecenterPose(hmd);
473 break;
475 case 'f':
476 /* press f to move the window to the HMD */
477 toggle_hmd_fullscreen();
478 break;
480 default:
481 break;
482 }
483 }
484 return 0;
485 }
487 unsigned int next_pow2(unsigned int x)
488 {
489 x -= 1;
490 x |= x >> 1;
491 x |= x >> 2;
492 x |= x >> 4;
493 x |= x >> 8;
494 x |= x >> 16;
495 return x + 1;
496 }
498 /* convert a quaternion to a rotation matrix */
499 void quat_to_matrix(const float *quat, float *mat)
500 {
501 mat[0] = 1.0 - 2.0 * quat[1] * quat[1] - 2.0 * quat[2] * quat[2];
502 mat[4] = 2.0 * quat[0] * quat[1] + 2.0 * quat[3] * quat[2];
503 mat[8] = 2.0 * quat[2] * quat[0] - 2.0 * quat[3] * quat[1];
504 mat[12] = 0.0f;
506 mat[1] = 2.0 * quat[0] * quat[1] - 2.0 * quat[3] * quat[2];
507 mat[5] = 1.0 - 2.0 * quat[0]*quat[0] - 2.0 * quat[2]*quat[2];
508 mat[9] = 2.0 * quat[1] * quat[2] + 2.0 * quat[3] * quat[0];
509 mat[13] = 0.0f;
511 mat[2] = 2.0 * quat[2] * quat[0] + 2.0 * quat[3] * quat[1];
512 mat[6] = 2.0 * quat[1] * quat[2] - 2.0 * quat[3] * quat[0];
513 mat[10] = 1.0 - 2.0 * quat[0]*quat[0] - 2.0 * quat[1]*quat[1];
514 mat[14] = 0.0f;
516 mat[3] = mat[7] = mat[11] = 0.0f;
517 mat[15] = 1.0f;
518 }
520 /* generate a chessboard texture with tiles colored (r0, g0, b0) and (r1, g1, b1) */
521 unsigned int gen_chess_tex(float r0, float g0, float b0, float r1, float g1, float b1)
522 {
523 int i, j;
524 unsigned int tex;
525 unsigned char img[8 * 8 * 3];
526 unsigned char *pix = img;
528 for(i=0; i<8; i++) {
529 for(j=0; j<8; j++) {
530 int black = (i & 1) == (j & 1);
531 pix[0] = (black ? r0 : r1) * 255;
532 pix[1] = (black ? g0 : g1) * 255;
533 pix[2] = (black ? b0 : b1) * 255;
534 pix += 3;
535 }
536 }
538 glGenTextures(1, &tex);
539 glBindTexture(GL_TEXTURE_2D, tex);
540 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
541 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
542 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 8, 8, 0, GL_RGB, GL_UNSIGNED_BYTE, img);
544 return tex;
545 }