src/libovr/ovr.c

   1 /* OVR handling
   2  *
   3  * (C) 2018 by Andreas Eversberg <jolly@eversberg.eu>
   4  * All Rights Reserved
   5  *
   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.
  10  *
  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.
  15  *
  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/>.
  18  *
  19  * Based on example code:
  20  * Filename    :   main.cpp
  21  * Content     :   Simple minimal VR demo
  22  * Created     :   December 1, 2014
  23  * Author      :   Tom Heath
  24  * Copyright   :   Copyright 2012 Oculus, Inc. All Rights reserved.
  25  *
  26  * Licensed under the Apache License, Version 2.0 (the "License");
  27  * you may not use this file except in compliance with the License.
  28  * You may obtain a copy of the License at
  29  *
  30  * http://www.apache.org/licenses/LICENSE-2.0
  31  *
  32  * Unless required by applicable law or agreed to in writing, software
  33  * distributed under the License is distributed on an "AS IS" BASIS,
  34  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  35  * See the License for the specific language governing permissions and
  36  * limitations under the License.
  37  */
  38
  39 #include <stdio.h>
  40 #include <stdint.h>
  41 #include <string.h>
  42 #include <math.h>
  43 #include <errno.h>
  44 #include "../libsdl/print.h"
  45 #include "ovr.h"
  46
  47 #include <OVR_CAPI.h>
  48 #include <OVR_CAPI_GL.h>
  49 #include "helper.h"
  50
  51 #define GL3_PROTOTYPES 1
  52 #include <GL/glew.h>
  53
  54 #if 0
  55 #if defined(_WIN32)
  56     #include <dxgi.h> // for GetDefaultAdapterLuid
  57     #pragma comment(lib, "dxgi.lib")
  58 #endif
  59
  60 static ovrGraphicsLuid GetDefaultAdapterLuid()
  61 {
  62         ovrGraphicsLuid luid = ovrGraphicsLuid();
  63
  64 #if defined(_WIN32)
  65         IDXGIFactory* factory = nullptr;
  66
  67         if (SUCCEEDED(CreateDXGIFactory(IID_PPV_ARGS(&factory)))) {
  68                 IDXGIAdapter* adapter = nullptr;
  69
  70                 if (SUCCEEDED(factory->EnumAdapters(0, &adapter))) {
  71                         DXGI_ADAPTER_DESC desc;
  72
  73                         adapter->GetDesc(&desc);
  74                         memcpy(&luid, &desc.AdapterLuid, sizeof(luid));
  75                         adapter->Release();
  76                 }
  77
  78                 factory->Release();
  79         }
  80 #endif
  81
  82         return luid;
  83 }
  84
  85 static int Compare(const ovrGraphicsLuid lhs, const ovrGraphicsLuid rhs)
  86 {
  87     return memcmp(&lhs, &rhs, sizeof(ovrGraphicsLuid));
  88 }
  89 #endif
  90
  91 static int ovr_initialized = 0;
  92 static ovrSession session = NULL;
  93 static ovrGraphicsLuid luid;
  94 static ovrHmdDesc hmdDesc;
  95 static ovrSizei TextureSize[2];
  96 static ovrTextureSwapChain textureSwapChain[2] = { NULL, NULL };
  97 static GLuint fboId[2] = { 0, 0 };
  98 static GLuint mirrorFBO = 0;
  99 static int mirror_width;
 100 static int mirror_height;
 101 static ovrEyeRenderDesc eyeRenderDesc[2];
 102 static ovrPosef hmdToEyeViewPose[2];
 103 static ovrLayerEyeFov layer;
 104 static int multisampling;
 105 static long long frameIndex = 0;
 106 static double observer_x = 0.0;
 107 static double observer_x_normalize = 0.0;
 108 static double observer_y = 0.0;
 109 static double observer_y_normalize = 0.0;
 110 static double observer_z = 0.0;
 111 static double observer_z_normalize = 0.0;
 112
 113 int init_ovr(int _multisampling)
 114 {
 115         ovrResult result;
 116         int eye;
 117
 118         multisampling = _multisampling;
 119
 120         glewExperimental = GL_TRUE;
 121         if (glewInit() != GLEW_OK) {
 122                 print_error("Failed to init GLEW\n");
 123                 goto error;
 124         }
 125
 126         result = ovr_Initialize(NULL);
 127         if (OVR_FAILURE(result)) {
 128                 print_error("Failed to init OVR (is Oculus Rift service running?)\n");
 129                 goto error;
 130         }
 131         ovr_initialized = 1;
 132
 133         result = ovr_Create(&session, &luid);
 134         if (OVR_FAILURE(result)) {
 135                 print_error("Failed to create OVR session (is the HMD connected?)\n");
 136                 goto error;
 137         }
 138
 139 #if 0
 140         if (Compare(luid, GetDefaultAdapterLuid())) { // If luid that the Rift is on is not the default adapter LUID...
 141                 print_error("OpenGL supports only the default graphics adapter.\n");
 142                 goto error;
 143         }
 144 #endif
 145
 146         hmdDesc = ovr_GetHmdDesc(session);
 147
 148         memset(&layer, 0, sizeof(layer));
 149         layer.Header.Type      = ovrLayerType_EyeFov;
 150         layer.Header.Flags     = 0;
 151
 152         /* do we need this??? seems to work without */
 153         if (multisampling > 1)
 154                 glEnable(GL_MULTISAMPLE);
 155
 156         /* create render buffers */
 157         for (eye = 0; eye < 2; eye++) {
 158                 TextureSize[eye] = ovr_GetFovTextureSize(session, (eye == 0) ? ovrEye_Left : ovrEye_Right, hmdDesc.DefaultEyeFov[eye], 1.0);
 159                 ovrTextureSwapChainDesc desc;
 160                 int length, i;
 161                 GLuint chainTexId;
 162
 163                 memset(&desc, 0, sizeof(desc));
 164                 desc.Type = ovrTexture_2D;
 165                 desc.ArraySize = 1;
 166                 desc.Format = OVR_FORMAT_R8G8B8A8_UNORM_SRGB;
 167                 desc.Width = TextureSize[eye].w;
 168                 desc.Height = TextureSize[eye].h;
 169                 desc.MipLevels = 1;
 170                 desc.SampleCount = (multisampling > 1) ? multisampling : 1;
 171                 desc.StaticImage = ovrFalse;
 172
 173                 result = ovr_CreateTextureSwapChainGL(session, &desc, &textureSwapChain[eye]);
 174                 if (OVR_FAILURE(result)) {
 175                         print_error("ovr_CreateTextureSwapChainGL() failed! (error %d)\n", result);
 176                         goto error;
 177                 }
 178
 179                 ovr_GetTextureSwapChainLength(session, textureSwapChain[eye], &length);
 180                 for (i = 0; i < length; i++) {
 181                         ovr_GetTextureSwapChainBufferGL(session, textureSwapChain[eye], i, &chainTexId);
 182                         glBindTexture((multisampling > 1) ? GL_TEXTURE_2D_MULTISAMPLE : GL_TEXTURE_2D, chainTexId);
 183                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 184                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 185                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 186                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 187                 }
 188
 189                 glGenFramebuffers(1, &(fboId[eye]));
 190
 191                 eyeRenderDesc[eye] = ovr_GetRenderDesc(session, (eye == 0) ? ovrEye_Left : ovrEye_Right, hmdDesc.DefaultEyeFov[eye]);
 192                 hmdToEyeViewPose[eye] = eyeRenderDesc[eye].HmdToEyePose;
 193
 194                 layer.ColorTexture[eye]  = textureSwapChain[eye];
 195                 layer.Fov[eye]           = eyeRenderDesc[eye].Fov;
 196                 layer.Viewport[eye].Pos.x = 0;
 197                 layer.Viewport[eye].Pos.y = 0;
 198                 layer.Viewport[eye].Size.w = TextureSize[eye].w;
 199                 layer.Viewport[eye].Size.h = TextureSize[eye].h;
 200         }
 201
 202         ovrMirrorTexture mirrorTexture = NULL;
 203         ovrMirrorTextureDesc desc;
 204         memset(&desc, 0, sizeof(desc));
 205         desc.Width = mirror_width = TextureSize[0].w;
 206         desc.Height = mirror_height = TextureSize[0].h / 2;
 207         desc.Format = OVR_FORMAT_R8G8B8A8_UNORM_SRGB;
 208         desc.MirrorOptions =
 209                 ovrMirrorOption_PostDistortion |
 210                 ovrMirrorOption_IncludeGuardian |
 211                 ovrMirrorOption_IncludeNotifications |
 212                 ovrMirrorOption_IncludeSystemGui;
 213
 214         /* Create mirror texture and an FBO used to copy mirror texture to back buffer */
 215         result = ovr_CreateMirrorTextureWithOptionsGL(session, &desc, &mirrorTexture);
 216         if (!OVR_SUCCESS(result)) {
 217                 print_error("ovr_CreateMirrorTextureWithOptionsGL() failed! (error %d)\n", result);
 218                 goto error;
 219         }
 220
 221         /* Configure the mirror read buffer */
 222         GLuint texId;
 223         ovr_GetMirrorTextureBufferGL(session, mirrorTexture, &texId);
 224
 225         glGenFramebuffers(1, &mirrorFBO);
 226         glBindFramebuffer(GL_READ_FRAMEBUFFER, mirrorFBO);
 227         glFramebufferTexture2D(GL_READ_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texId, 0);
 228         glFramebufferRenderbuffer(GL_READ_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, 0);
 229
 230         return 0;
 231
 232 error:
 233         exit_ovr();
 234         return -EINVAL;
 235 }
 236
 237 void begin_render_ovr(void)
 238 {
 239         ovrResult result;
 240
 241         /* Get both eye poses simultaneously, with IPD offset already included. */
 242         double displayMidpointSeconds = ovr_GetPredictedDisplayTime(session, 0);
 243         ovrTrackingState hmdState = ovr_GetTrackingState(session, displayMidpointSeconds, ovrTrue);
 244         ovr_CalcEyePoses(hmdState.HeadPose.ThePose, hmdToEyeViewPose, layer.RenderPose);
 245
 246         result = ovr_WaitToBeginFrame(session, frameIndex);
 247         if (!OVR_SUCCESS(result))
 248                 print_info("Failed to wait to begin frame (error %d)\n", result);
 249         result = ovr_BeginFrame(session, frameIndex);
 250         if (!OVR_SUCCESS(result))
 251                 print_info("Failed to begin frame (error %d)\n", result);
 252 }
 253
 254 void begin_render_ovr_eye(int eye)
 255 {
 256         int curIndex;
 257         GLuint chainTexId;
 258         float yaw, pitch, roll;
 259         double x, y, z;
 260
 261         /* set render surface */
 262         ovr_GetTextureSwapChainCurrentIndex(session, textureSwapChain[eye], &curIndex);
 263         ovr_GetTextureSwapChainBufferGL(session, textureSwapChain[eye], curIndex, &chainTexId);
 264         glBindFramebuffer(GL_FRAMEBUFFER, fboId[eye]);
 265         glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, (multisampling > 1) ? GL_TEXTURE_2D_MULTISAMPLE : GL_TEXTURE_2D, chainTexId, 0);
 266
 267         glViewport(0, 0, TextureSize[eye].w, TextureSize[eye].h);
 268         glMatrixMode(GL_PROJECTION);
 269         glLoadIdentity();
 270         glFrustum(
 271                 -layer.Fov[eye].LeftTan,
 272                 layer.Fov[eye].RightTan,
 273                 layer.Fov[eye].UpTan,
 274                 -layer.Fov[eye].DownTan,
 275                 1.0, 5000000000.0);
 276
 277         ovrOrientation2yawpitchroll(layer.RenderPose[eye].Orientation, &yaw, &pitch, &roll);
 278         x = layer.RenderPose[eye].Position.x;
 279         y = layer.RenderPose[eye].Position.y;
 280         z = layer.RenderPose[eye].Position.z;
 281
 282         /* normalize height to game's observer, if requrested by user */
 283         observer_x = x;
 284         x += observer_x_normalize;
 285         observer_y = y;
 286         y += observer_y_normalize;
 287         observer_z = z;
 288         z += observer_z_normalize;
 289
 290         glRotatef(-roll / M_PI * 180.0,0,0,1);
 291         glRotatef(-pitch / M_PI * 180.0,1,0,0);
 292         glRotatef(-yaw / M_PI * 180.0,0,1,0);
 293
 294         glTranslated(-x / 0.0254, -y / 0.0254, -z / 0.0254); /* convert to inch */
 295
 296         glMatrixMode(GL_MODELVIEW);
 297
 298         /* DO NOT ENABLE, since our mercenary-textures are not SRGB */
 299         //glEnable(GL_FRAMEBUFFER_SRGB);
 300
 301 }
 302
 303 void end_render_ovr_eye(int eye)
 304 {
 305         // unset render surface
 306         glBindFramebuffer(GL_FRAMEBUFFER, fboId[eye]);
 307         glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, (multisampling > 1) ? GL_TEXTURE_2D_MULTISAMPLE : GL_TEXTURE_2D, 0, 0);
 308         glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, (multisampling > 1) ? GL_TEXTURE_2D_MULTISAMPLE : GL_TEXTURE_2D, 0, 0);
 309         glBindFramebuffer(GL_FRAMEBUFFER, 0);
 310
 311         // Commit the changes to the texture swap chain
 312         ovr_CommitTextureSwapChain(session, textureSwapChain[eye]);
 313 }
 314
 315 void end_render_ovr(void)
 316 {
 317         ovrResult result;
 318
 319         const ovrLayerHeader *layers[] = { &layer.Header };
 320         result = ovr_EndFrame(session, frameIndex, NULL, layers, 1);
 321         if (!OVR_SUCCESS(result))
 322                 print_info("Failed to submit frame (error %d)\n", result);
 323         frameIndex++;
 324 }
 325
 326 void render_mirror_ovr(int view_width, int view_height)
 327 {
 328         int view_x = 0, view_y = 0;
 329         int new_width, new_height;
 330
 331         /* avoid division by zero, if one dimension is too small */
 332         if (view_width < 1 || view_height < 1)
 333                 return;
 334
 335         /* calculate a viewport that has apect of TextureSize */
 336         if (view_height * mirror_width > view_width * mirror_height) {
 337                 new_height = view_width * mirror_height / mirror_width;
 338                 view_y = view_y + view_height / 2 - new_height / 2;
 339                 view_height = new_height;
 340         } else if (view_height * mirror_width < view_width * mirror_height) {
 341                 new_width = view_height * mirror_width / mirror_height;
 342                 view_x = view_x + view_width / 2 - new_width / 2;
 343                 view_width = new_width;
 344         }
 345
 346         /* avoid views that are too small */
 347         if (view_width < 1 || view_height < 1)
 348                 return;
 349
 350         glBindFramebuffer(GL_FRAMEBUFFER, 0);
 351
 352         glClearColor(0.0, 0.0, 0.0, 1.0);
 353         glClear(GL_COLOR_BUFFER_BIT);
 354
 355         /* Blit mirror texture to back buffer */
 356         glBindFramebuffer(GL_READ_FRAMEBUFFER, mirrorFBO);
 357         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
 358         glBlitFramebuffer(0, mirror_height, mirror_width, 0,
 359                 view_x, view_y, view_x + view_width, view_y + view_height,
 360                 GL_COLOR_BUFFER_BIT, GL_NEAREST);
 361         glBindFramebuffer(GL_READ_FRAMEBUFFER, 0);
 362 }
 363
 364 void normalize_observer_ovr(void)
 365 {
 366         observer_x_normalize = -observer_x;
 367         observer_y_normalize = -observer_y;
 368         observer_z_normalize = -observer_z;
 369 }
 370
 371 void exit_ovr(void)
 372 {
 373         int eye;
 374
 375         /* destroy render buffers */
 376         for (eye = 0; eye < 2; eye++) {
 377                 if (textureSwapChain[eye]) {
 378                         ovr_DestroyTextureSwapChain(session, textureSwapChain[eye]);
 379                         textureSwapChain[eye] = NULL;
 380                 }
 381                 if (fboId[eye]) {
 382                         glDeleteFramebuffers(1, &fboId[eye]);
 383                         fboId[eye] = 0;
 384                 }
 385         }
 386         if (mirrorFBO) {
 387                 glDeleteFramebuffers(1, &mirrorFBO);
 388                 mirrorFBO = 0;
 389         }
 390
 391         if (session) {
 392                 ovr_Destroy(session);
 393                 session = NULL;
 394         }
 395         if (ovr_initialized) {
 396                 ovr_Shutdown();
 397                 ovr_initialized = 0;
 398         }
 399 }
 400