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 ovrEyeRenderDesc eyeRenderDesc[2];
  99 static ovrPosef hmdToEyeViewPose[2];
 100 static ovrLayerEyeFov layer;
 101 static long long frameIndex = 0;
 102
 103 int init_ovr(void)
 104 {
 105         int sample_count = 1; // FIXME: make MSAA
 106         ovrResult result;
 107         int eye;
 108
 109         glewExperimental = GL_TRUE;
 110         if (glewInit() != GLEW_OK) {
 111                 print_error("Failed to init GLEW\n");
 112                 goto error;
 113         }
 114
 115         result = ovr_Initialize(NULL);
 116         if (OVR_FAILURE(result)) {
 117                 print_error("Failed to init OVR (is Oculus Rift service running?)\n");
 118                 goto error;
 119         }
 120         ovr_initialized = 1;
 121
 122         result = ovr_Create(&session, &luid);
 123         if (OVR_FAILURE(result)) {
 124                 print_error("Failed to create OVR session (is the HMD connected?)\n");
 125                 goto error;
 126         }
 127
 128 #if 0
 129         if (Compare(luid, GetDefaultAdapterLuid())) { // If luid that the Rift is on is not the default adapter LUID...
 130                 print_error("OpenGL supports only the default graphics adapter.\n");
 131                 goto error;
 132         }
 133 #endif
 134
 135         hmdDesc = ovr_GetHmdDesc(session);
 136
 137         memset(&layer, 0, sizeof(layer));
 138         layer.Header.Type      = ovrLayerType_EyeFov;
 139         layer.Header.Flags     = 0;
 140
 141         /* create render buffers */
 142         for (eye = 0; eye < 2; eye++) {
 143                 TextureSize[eye] = ovr_GetFovTextureSize(session, (eye == 0) ? ovrEye_Left : ovrEye_Right, hmdDesc.DefaultEyeFov[eye], 1.0);
 144 #warning hacking resolution
 145 //TextureSize[eye].w *= 2;
 146 //TextureSize[eye].h *= 2;
 147                 ovrTextureSwapChainDesc desc;
 148                 int length, i;
 149                 GLuint chainTexId;
 150
 151                 memset(&desc, 0, sizeof(desc));
 152                 desc.Type = ovrTexture_2D;
 153                 desc.ArraySize = 1;
 154                 desc.Format = OVR_FORMAT_R8G8B8A8_UNORM_SRGB;
 155                 desc.Width = TextureSize[eye].w;
 156                 desc.Height = TextureSize[eye].h;
 157                 desc.MipLevels = 1;
 158                 desc.SampleCount = sample_count;
 159                 desc.StaticImage = ovrFalse;
 160
 161                 result = ovr_CreateTextureSwapChainGL(session, &desc, &textureSwapChain[eye]);
 162                 if (OVR_FAILURE(result)) {
 163                         print_error("ovr_CreateTextureSwapChainGL() failed!\n");
 164                         goto error;
 165                 }
 166
 167                 ovr_GetTextureSwapChainLength(session, textureSwapChain[eye], &length);
 168                 for (i = 0; i < length; i++) {
 169                         ovr_GetTextureSwapChainBufferGL(session, textureSwapChain[eye], i, &chainTexId);
 170                         glBindTexture(GL_TEXTURE_2D, chainTexId);
 171                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 172                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 173                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 174                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 175                 }
 176
 177                 glGenFramebuffers(1, &(fboId[eye]));
 178
 179                 eyeRenderDesc[eye] = ovr_GetRenderDesc(session, (eye == 0) ? ovrEye_Left : ovrEye_Right, hmdDesc.DefaultEyeFov[eye]);
 180                 hmdToEyeViewPose[eye] = eyeRenderDesc[eye].HmdToEyePose;
 181
 182                 layer.ColorTexture[eye]  = textureSwapChain[eye];
 183                 layer.Fov[eye]           = eyeRenderDesc[eye].Fov;
 184                 layer.Viewport[eye].Pos.x = 0;
 185                 layer.Viewport[eye].Pos.y = 0;
 186                 layer.Viewport[eye].Size.w = TextureSize[eye].w;
 187                 layer.Viewport[eye].Size.h = TextureSize[eye].h;
 188         }
 189
 190
 191         return 0;
 192
 193 error:
 194         exit_ovr();
 195         return -EINVAL;
 196 }
 197
 198 void begin_render_ovr(void)
 199 {
 200         ovrResult result;
 201
 202         /* Get both eye poses simultaneously, with IPD offset already included. */
 203         double displayMidpointSeconds = ovr_GetPredictedDisplayTime(session, 0);
 204         ovrTrackingState hmdState = ovr_GetTrackingState(session, displayMidpointSeconds, ovrTrue);
 205         ovr_CalcEyePoses(hmdState.HeadPose.ThePose, hmdToEyeViewPose, layer.RenderPose);
 206
 207         result = ovr_WaitToBeginFrame(session, frameIndex);
 208         if (!OVR_SUCCESS(result))
 209                 print_info("Failed to wait to begin frame (error %d)\n", result);
 210         result = ovr_BeginFrame(session, frameIndex);
 211         if (!OVR_SUCCESS(result))
 212                 print_info("Failed to begin frame (error %d)\n", result);
 213 }
 214
 215 void begin_render_ovr_eye(int eye)
 216 {
 217         int curIndex;
 218         GLuint chainTexId;
 219         float yaw, pitch, roll;
 220         double x, y, z;
 221
 222         /* set render surface */
 223         ovr_GetTextureSwapChainCurrentIndex(session, textureSwapChain[eye], &curIndex);
 224         ovr_GetTextureSwapChainBufferGL(session, textureSwapChain[eye], curIndex, &chainTexId);
 225         glBindFramebuffer(GL_FRAMEBUFFER, fboId[eye]);
 226         glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, chainTexId, 0);
 227
 228         glViewport(0, 0, TextureSize[eye].w, TextureSize[eye].h);
 229         glMatrixMode(GL_PROJECTION);
 230         glLoadIdentity();
 231         glFrustum(
 232                 -layer.Fov[eye].LeftTan,
 233                 layer.Fov[eye].RightTan,
 234                 layer.Fov[eye].UpTan,
 235                 -layer.Fov[eye].DownTan,
 236                 1.0, 5000000000.0);
 237
 238         ovrOrientation2yawpitchroll(layer.RenderPose[eye].Orientation, &yaw, &pitch, &roll);
 239         x = layer.RenderPose[eye].Position.x;
 240         y = layer.RenderPose[eye].Position.y;
 241         z = layer.RenderPose[eye].Position.z;
 242
 243         glRotatef(-roll / M_PI * 180.0,0,0,1);
 244         glRotatef(-pitch / M_PI * 180.0,1,0,0);
 245         glRotatef(-yaw / M_PI * 180.0,0,1,0);
 246
 247         glTranslated(-x / 0.0254, -y / 0.0254, -z / 0.0254); /* convert to inch */
 248
 249         glMatrixMode(GL_MODELVIEW);
 250
 251         /* DO NOT ENABLE, since our mercenary-textures are not SRGB */
 252         //glEnable(GL_FRAMEBUFFER_SRGB);
 253
 254 }
 255
 256 void end_render_ovr_eye(int eye)
 257 {
 258         // unset render surface
 259         glBindFramebuffer(GL_FRAMEBUFFER, fboId[eye]);
 260         glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
 261         glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, 0, 0);
 262         glBindFramebuffer(GL_FRAMEBUFFER, 0);
 263
 264         // Commit the changes to the texture swap chain
 265         ovr_CommitTextureSwapChain(session, textureSwapChain[eye]);
 266 }
 267
 268 void end_render_ovr(void)
 269 {
 270         ovrResult result;
 271
 272         const ovrLayerHeader *layers[] = { &layer.Header };
 273         result = ovr_EndFrame(session, frameIndex, NULL, layers, 1);
 274         if (!OVR_SUCCESS(result))
 275                 print_info("Failed to submit frame (error %d)\n", result);
 276         frameIndex++;
 277 }
 278
 279 void render_mirror_ovr(int view_width, int view_height)
 280 {
 281         int eye = 0; /* left eye */
 282         int curIndex;
 283         GLuint chainTexId;
 284
 285         /* clear screen */
 286         glClearColor(1.0, 0.0, 0.0, 1.0);
 287         glClear(GL_COLOR_BUFFER_BIT);
 288
 289         /* orthogonal viewport */
 290         glViewport((GLsizei)0, (GLsizei)0, (GLsizei)view_width, (GLsizei)view_height);
 291         glMatrixMode(GL_PROJECTION);
 292         glLoadIdentity();
 293         glOrtho(-1.0, 1.0, -1.0, 1.0, -1.0, 1.0);
 294         glMatrixMode(GL_MODELVIEW);
 295
 296         /* get texture from OVR */
 297         ovr_GetTextureSwapChainCurrentIndex(session, textureSwapChain[eye], &curIndex);
 298         ovr_GetTextureSwapChainBufferGL(session, textureSwapChain[eye], curIndex, &chainTexId);
 299
 300         /* render mirror from texture */
 301         glEnable(GL_TEXTURE_2D);
 302         glBindTexture(GL_TEXTURE_2D, chainTexId);
 303         glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);  /* no modulation with color */
 304         glBegin(GL_QUADS);
 305         glTexCoord2f(0, 1);
 306         glVertex3f(-1.0, -1.0, 0.0);
 307         glTexCoord2f(1, 1);
 308         glVertex3f(1.0, -1.0, 0.0);
 309         glTexCoord2f(1, 0);
 310         glVertex3f(1.0, 1.0, 0.0);
 311         glTexCoord2f(0, 0);
 312         glVertex3f(-1.0, 1.0, 0.0);
 313         glEnd();
 314         glDisable(GL_TEXTURE_2D);
 315 }
 316
 317 void exit_ovr(void)
 318 {
 319         int eye;
 320
 321         /* destroy render buffers */
 322         for (eye = 0; eye < 2; eye++) {
 323                 if (textureSwapChain[eye]) {
 324                         ovr_DestroyTextureSwapChain(session, textureSwapChain[eye]);
 325                         textureSwapChain[eye] = NULL;
 326                 }
 327                 if (fboId[eye]) {
 328                         glDeleteFramebuffers(1, &fboId[eye]);
 329                         fboId[eye] = 0;
 330                 }
 331         }
 332
 333         if (session) {
 334                 ovr_Destroy(session);
 335                 session = NULL;
 336         }
 337         if (ovr_initialized) {
 338                 ovr_Shutdown();
 339                 ovr_initialized = 0;
 340         }
 341 }
 342