nuclear@0: #include <stdio.h>
nuclear@0: #include <stdlib.h>
nuclear@0: #include <SDL2/SDL.h>
nuclear@0: #include <GL/glew.h>
nuclear@0: 
nuclear@0: #include <OVR_CAPI.h>
nuclear@0: #include <OVR_CAPI_GL.h>
nuclear@0: 
nuclear@0: int init();
nuclear@0: void cleanup();
nuclear@0: void display();
nuclear@0: void update_rtarg(int width, int height);
nuclear@0: int handle_event(SDL_Event *ev);
nuclear@0: int key_event(int key, int state);
nuclear@0: void reshape(int x, int y);
nuclear@0: unsigned int next_pow2(unsigned int x);
nuclear@0: 
nuclear@0: OVR_EXPORT void ovrhmd_EnableHSWDisplaySDKRender(ovrHmd hmd, ovrBool enable);
nuclear@0: 
nuclear@0: static SDL_Window *win;
nuclear@0: static SDL_GLContext ctx;
nuclear@0: 
nuclear@0: static unsigned int fbo, fb_tex, fb_depth;
nuclear@0: static int fb_width, fb_height;
nuclear@0: static int fb_tex_width, fb_tex_height;
nuclear@0: 
nuclear@0: static ovrHmd hmd;
nuclear@0: static ovrSizei eyeres[2];
nuclear@0: 
nuclear@0: 
nuclear@0: int main(void)
nuclear@0: {
nuclear@0: 	if(init() == -1) {
nuclear@0: 		return 1;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	for(;;) {
nuclear@0: 		SDL_Event ev;
nuclear@0: 
nuclear@0: 		while(SDL_PollEvent(&ev)) {
nuclear@0: 			if(handle_event(&ev) == -1) {
nuclear@0: 				goto done;
nuclear@0: 			}
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		display();
nuclear@0: 	}
nuclear@0: 
nuclear@0: done:
nuclear@0: 	cleanup();
nuclear@0: 	return 0;
nuclear@0: }
nuclear@0: 
nuclear@0: 
nuclear@0: int init()
nuclear@0: {
nuclear@0: 	int x, y;
nuclear@0: 	unsigned int flags, dcaps;
nuclear@0: 	union ovrGLConfig glcfg;
nuclear@0: 	ovrEyeRenderDesc eye_rdesc[2];
nuclear@0: 
nuclear@0: 	// this must be called before any OpenGL init according to the docs
nuclear@0: 	ovr_Initialize();
nuclear@0: 
nuclear@0: 	SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER);
nuclear@0: 
nuclear@0: 	x = y = SDL_WINDOWPOS_UNDEFINED;
nuclear@0: 	flags = SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE;
nuclear@0: 	if(!(win = SDL_CreateWindow("simple oculus example", x, y, 1280, 800, flags))) {
nuclear@0: 		fprintf(stderr, "failed to create window\n");
nuclear@0: 		return -1;
nuclear@0: 	}
nuclear@0: 	if(!(ctx = SDL_GL_CreateContext(win))) {
nuclear@0: 		fprintf(stderr, "failed to create OpenGL context\n");
nuclear@0: 		return -1;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	glewInit();
nuclear@0: 
nuclear@0: 	if(!(hmd = ovrHmd_Create(0))) {
nuclear@0: 		fprintf(stderr, "failed to open Oculus HMD, falling back to virtual debug HMD\n");
nuclear@0: 		if(!(hmd = ovrHmd_CreateDebug())) {
nuclear@0: 			fprintf(stderr, "failed to create virtual debug HMD\n");
nuclear@0: 			return -1;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 	printf("initialized HMD: %s - %s\n", hmd->Manufacturer, hmd->ProductName);
nuclear@0: 
nuclear@0: 	SDL_SetWindowSize(hmd->Resolution.w, hmd->Resolution.h);
nuclear@0: 
nuclear@0: 	ovrHmd_ConfigureTracking(hmd, 0xffffffff, 0);
nuclear@0: 	eyeres[0] = ovrHmd_GetFovTextureSize(hmd, ovrEye_Left, hmd->DefaultEyeFov[0], 1.0);
nuclear@0: 	eyeres[1] = ovrHmd_GetFovTextureSize(hmd, ovrEye_Right, hmd->DefaultEyeFov[1], 1.0);
nuclear@0: 
nuclear@0: 	fb_width = eyeres[0].w + eyres[1].w;
nuclear@0: 	fb_height = eyeres[0].h > eyeres[1].h ? eyeres[0].h : eyeres[1].h;
nuclear@0: 	update_rtarg(fb_width, fb_height);
nuclear@0: 
nuclear@0: 	memset(&glcfg, 0, sizeof glcfg);
nuclear@0: 	glcfg.OGL.Header.API = ovrRenderAPI_OpenGL;
nuclear@0: 	glcfg.OGL.Header.RTSize = hmd->Resolution;
nuclear@0: 	glcfg.OGL.Header.Multisample = 1;
nuclear@0: 
nuclear@0: 	if(hmd->HmdCaps & ovrHmdCap_ExtendDesktop) {
nuclear@0: 		printf("running in \"extended desktop\" mode\n");
nuclear@0: 	} else {
nuclear@0: 		printf("running in \"direct-hmd\" mode\n");
nuclear@0: #ifdef WIN32
nuclear@0: 		ovrHmd_AttachToWindow(hmd, GetActiveWindow(), 0, 0);
nuclear@0: #endif
nuclear@0: 	}
nuclear@0: 	ovrHmd_SetEnabledCaps(hmd, ovrHmdCap_LowPersistence | ovrHmdCaps_DynamicPrediction);
nuclear@0: 
nuclear@0: 	dcaps = ovrDistortionCap_Chromatic | ovrDistortionCap_Vignette | ovrDistortionCap_TimeWrap;
nuclear@0: 	if(!ovrHmd_ConfigureRendering(hmd, &glcfg.Config, dcaps, hmd->DefaultEyeFov, eye_rdesc)) {
nuclear@0: 		fprintf(stderr, "failed to configure distortion renderer\n");
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	ovrhmd_EnableHSWDisplaySDKRender(hmd, 0);
nuclear@0: 
nuclear@0: 
nuclear@0: 	glEnable(GL_DEPTH_TEST);
nuclear@0: 	glEnable(GL_CULL_FACE);
nuclear@0: 	glEnable(GL_LIGHTING);
nuclear@0: 	glEnable(GL_LIGHT0);
nuclear@0: 
nuclear@0: 	glClearColor(0.05, 0.05, 0.05, 1);
nuclear@0: 
nuclear@0: 	return 0;
nuclear@0: }
nuclear@0: 
nuclear@0: void cleanup()
nuclear@0: {
nuclear@0: 	if(hmd) {
nuclear@0: 		ovrHmd_Destroy(hmd);
nuclear@0: 	}
nuclear@0: 	ovr_Shutdown();
nuclear@0: 
nuclear@0: 	SDL_Quit();
nuclear@0: }
nuclear@0: 
nuclear@0: void display()
nuclear@0: {
nuclear@0: 	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
nuclear@0: 
nuclear@0: 	SDL_GL_SwapWindow(win);
nuclear@0: }
nuclear@0: 
nuclear@0: void update_rtarg(int width, int height)
nuclear@0: {
nuclear@0: 	if(!fbo) {
nuclear@0: 		glGenFramebuffers(1, &fbo);
nuclear@0: 		glGenTextures(1, &fb_tex);
nuclear@0: 		glGenRenderbuffers(1, &fb_depth);
nuclear@0: 
nuclear@0: 		glBindTexture(GL_TEXTURE_2D, fb_tex);
nuclear@0: 		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
nuclear@0: 		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	glBindFramebuffer(GL_FRAMEBUFFER, fbo);
nuclear@0: 
nuclear@0: 	fb_tex_width = next_pow2(width);
nuclear@0: 	fb_tex_height = next_pow2(height);
nuclear@0: 
nuclear@0: 	glBindTexture(GL_TEXTURE_2D, fb_tex);
nuclear@0: 	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, fb_tex_width, fb_tex_height, 0,
nuclear@0: 			GL_RGBA, GL_UNSIGNED_BYTE, 0);
nuclear@0: 	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, fb_tex, 0);
nuclear@0: 
nuclear@0: 	glBindRenderbuffer(GL_RENDERBUFFER, fb_depth);
nuclear@0: 	glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, fb_tex_width, fb_tex_height);
nuclear@0: 	glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, fb_depth);
nuclear@0: 
nuclear@0: 	if(glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
nuclear@0: 		fprintf(stderr, "incomplete framebuffer!\n");
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	glBindFramebuffer(GL_FRAMEBUFFER, 0);
nuclear@0: 	printf("created render target: %dx%d (texture size: %dx%d)\n", width, height, fb_tex_width, fb_tex_height);
nuclear@0: }
nuclear@0: 
nuclear@0: int handle_event(SDL_Event *ev)
nuclear@0: {
nuclear@0: 	switch(ev->type) {
nuclear@0: 	case SDL_KEYDOWN:
nuclear@0: 	case SDL_KEYUP:
nuclear@0: 		if(key_event(ev->key.keysym.sym, ev->key.state == SDL_PRESSED) == -1) {
nuclear@0: 			return -1;
nuclear@0: 		}
nuclear@0: 		break;
nuclear@0: 
nuclear@0: 	default:
nuclear@0: 		break;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	return 0;
nuclear@0: }
nuclear@0: 
nuclear@0: int key_event(int key, int state)
nuclear@0: {
nuclear@0: 	if(state) {
nuclear@0: 		switch(key) {
nuclear@0: 		case 27:
nuclear@0: 			return -1;
nuclear@0: 
nuclear@0: 		default:
nuclear@0: 			break;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 	return 0;
nuclear@0: }