nuclear@15: #include <stdio.h>
nuclear@15: #include <stdlib.h>
nuclear@15: #include <string.h>
nuclear@15: #include <limits.h>
nuclear@18: #include <assert.h>
nuclear@15: #include "opengl.h"
nuclear@15: #include "renderer.h"
nuclear@15: #include "sdr.h"
nuclear@15: #include "datapath.h"
nuclear@15: 
nuclear@18: 
nuclear@17: static bool create_fbo(int xsz, int ysz);
nuclear@18: static unsigned int load_sdr(const char *vfname, const char *pfname);
nuclear@17: static int round_pow2(int x);
nuclear@15: 
nuclear@17: 
nuclear@18: #define MRT_COUNT	1
nuclear@17: static unsigned int mrt_tex[MRT_COUNT];
nuclear@17: 
nuclear@17: static unsigned int mrt_prog;
nuclear@18: static unsigned int deferred_omni, deferred_debug;
nuclear@17: 
nuclear@17: static unsigned int fbo, rbuf_depth;
nuclear@17: static const char *fbstname[] = {
nuclear@17: 	"GL_FRAMEBUFFER_COMPLETE",
nuclear@17: 	"GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT",
nuclear@17: 	"GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT",
nuclear@17: 	"no such fbo error",
nuclear@17: 	"GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS",
nuclear@17: 	"GL_FRAMEBUFFER_INCOMPLETE_FORMATS",
nuclear@17: 	"GL_FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER",
nuclear@17: 	"GL_FRAMEBUFFER_INCOMPLETE_READ_BUFFER",
nuclear@17: 	"GL_FRAMEBUFFER_UNSUPPORTED"
nuclear@15: };
nuclear@15: 
nuclear@17: static int fb_xsz, fb_ysz, tex_xsz, tex_ysz;
nuclear@15: 
nuclear@17: bool init_renderer(int xsz, int ysz)
nuclear@17: {
nuclear@17: 	if(!create_fbo(xsz, ysz)) {
nuclear@17: 		return false;
nuclear@17: 	}
nuclear@18: 
nuclear@18: 	if(!(mrt_prog = load_sdr("mrt.v.glsl", "mrt.p.glsl"))) {
nuclear@18: 		return false;
nuclear@18: 	}
nuclear@18: 	if(!(deferred_debug = load_sdr("deferred.v.glsl", "deferred.p.glsl"))) {
nuclear@17: 		return false;
nuclear@17: 	}
nuclear@17: 	return true;
nuclear@17: }
nuclear@17: 
nuclear@17: void destroy_renderer()
nuclear@17: {
nuclear@17: 	free_program(mrt_prog);
nuclear@17: 	free_program(deferred_omni);
nuclear@17: 
nuclear@17: 	glDeleteTextures(MRT_COUNT, mrt_tex);
nuclear@17: 	glDeleteFramebuffersEXT(1, &fbo);
nuclear@17: }
nuclear@17: 
nuclear@17: void render_deferred(void (*draw_func)())
nuclear@17: {
nuclear@18: 	int loc;
nuclear@18: 
nuclear@18: 	// render into the MRT buffers
nuclear@18: 	glBindFramebufferEXT(GL_FRAMEBUFFER, fbo);
nuclear@18: 	glUseProgram(mrt_prog);
nuclear@17: 	draw_func();
nuclear@18: 	glUseProgram(0);
nuclear@18: 	glBindFramebufferEXT(GL_FRAMEBUFFER, 0);
nuclear@18: 
nuclear@18: 
nuclear@18: 	// post-process lighting
nuclear@18: 	glPushAttrib(GL_ENABLE_BIT);
nuclear@18: 
nuclear@18: 	glDisable(GL_LIGHTING);
nuclear@18: 	glDisable(GL_DEPTH_TEST);
nuclear@18: 	glBindTexture(GL_TEXTURE_2D, mrt_tex[0]);
nuclear@18: 	glEnable(GL_TEXTURE_2D);
nuclear@18: 
nuclear@18: 	glUseProgram(deferred_debug);
nuclear@18: 	if((loc = glGetUniformLocation(deferred_debug, "tex0")) != -1) {
nuclear@18: 		glUniform1i(loc, 0);
nuclear@18: 	}
nuclear@18: 	if((loc = glGetUniformLocation(deferred_debug, "tex_scale")) != -1) {
nuclear@18: 		glUniform2f(loc, (float)fb_xsz / tex_xsz, (float)fb_ysz / tex_ysz);
nuclear@18: 	}
nuclear@18: 
nuclear@18: 	glBegin(GL_QUADS);
nuclear@18: 	glTexCoord2f(0, 0);
nuclear@18: 	glVertex2f(-1, -1);
nuclear@18: 	glTexCoord2f(1, 0);
nuclear@18: 	glVertex2f(1, -1);
nuclear@18: 	glTexCoord2f(1, 1);
nuclear@18: 	glVertex2f(1, 1);
nuclear@18: 	glTexCoord2f(0, 1);
nuclear@18: 	glVertex2f(-1, 1);
nuclear@18: 	glEnd();
nuclear@18: 
nuclear@18: 	glUseProgram(0);
nuclear@18: 	glPopAttrib();
nuclear@17: }
nuclear@17: 
nuclear@17: static bool create_fbo(int xsz, int ysz)
nuclear@17: {
nuclear@17: 	unsigned int clamp = GL_ARB_texture_border_clamp ? GL_CLAMP_TO_EDGE : GL_CLAMP;
nuclear@17: 
nuclear@17: 	tex_xsz = round_pow2(xsz);
nuclear@17: 	tex_ysz = round_pow2(ysz);
nuclear@17: 	fb_xsz = xsz;
nuclear@17: 	fb_ysz = ysz;
nuclear@17: 
nuclear@17: 	if(!glGenFramebuffersEXT) {
nuclear@17: 		fprintf(stderr, "FBO support missing\n");
nuclear@17: 		return false;
nuclear@17: 	}
nuclear@17: 	glGenFramebuffersEXT(1, &fbo);
nuclear@18: 	glBindFramebufferEXT(GL_FRAMEBUFFER, fbo);
nuclear@17: 
nuclear@17: 	glGenTextures(MRT_COUNT, mrt_tex);
nuclear@17: 	for(int i=0; i<MRT_COUNT; i++) {
nuclear@17: 		glBindTexture(GL_TEXTURE_2D, mrt_tex[i]);
nuclear@17: 		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, clamp);
nuclear@17: 		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, clamp);
nuclear@17: 		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
nuclear@17: 		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
nuclear@17: 		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, tex_xsz, tex_ysz, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);
nuclear@17: 
nuclear@17: 		// attach to fbo
nuclear@17: 		glFramebufferTexture2DEXT(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0 + i, GL_TEXTURE_2D,
nuclear@17: 				mrt_tex[i], 0);
nuclear@18: 		CHECKGLERR;
nuclear@17: 	}
nuclear@17: 
nuclear@18: 	glGenRenderbuffersEXT(1, &rbuf_depth);
nuclear@18: 	glBindRenderbufferEXT(GL_RENDERBUFFER, rbuf_depth);
nuclear@18: 	glRenderbufferStorageEXT(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, tex_xsz, tex_ysz);
nuclear@18: 	glFramebufferRenderbufferEXT(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, rbuf_depth);
nuclear@18: 
nuclear@17: 	int fbst = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER);
nuclear@17: 	if(fbst != GL_FRAMEBUFFER_COMPLETE) {
nuclear@17: 		fprintf(stderr, "incomplete fbo: %u (%s)\n", fbo, fbstname[fbst - GL_FRAMEBUFFER_COMPLETE]);
nuclear@17: 		return false;
nuclear@17: 	}
nuclear@18: 	CHECKGLERR;
nuclear@18: 
nuclear@18: 	glBindFramebufferEXT(GL_FRAMEBUFFER, 0);
nuclear@17: 	return true;
nuclear@17: }
nuclear@17: 
nuclear@18: static unsigned int load_sdr(const char *vfname, const char *pfname)
nuclear@15: {
nuclear@15: 	char vsfile[PATH_MAX], psfile[PATH_MAX];
nuclear@15: 	const char *fname;
nuclear@18: 	unsigned int prog;
nuclear@15: 
nuclear@18: 	if((fname = datafile_path(vfname))) {
nuclear@17: 		strcpy(vsfile, fname);
nuclear@17: 	} else {
nuclear@17: 		vsfile[0] = 0;
nuclear@17: 	}
nuclear@18: 	if((fname = datafile_path(pfname))) {
nuclear@17: 		strcpy(psfile, fname);
nuclear@17: 	} else {
nuclear@17: 		psfile[0] = 0;
nuclear@17: 	}
nuclear@18: 	if(!(prog = create_program_load(vsfile, psfile))) {
nuclear@18: 		fprintf(stderr, "failed to load shader program (%s, %s)\n", vsfile, psfile);
nuclear@18: 		return 0;
nuclear@15: 	}
nuclear@18: 	return prog;
nuclear@15: }
nuclear@15: 
nuclear@17: static int round_pow2(int x)
nuclear@15: {
nuclear@17: 	x--;
nuclear@17: 	x = (x >> 1) | x;
nuclear@17: 	x = (x >> 2) | x;
nuclear@17: 	x = (x >> 4) | x;
nuclear@17: 	x = (x >> 8) | x;
nuclear@17: 	x = (x >> 16) | x;
nuclear@17: 	return x + 1;
nuclear@15: }