Raw FBO, openFrameworks

openframeworks_fbo_test.cpp

#include "testApp.h"
#include "Error.h"
//--------------------------------------------------------------
void testApp::setup(){
	ofEnableNormalizedTexCoords();
	ofDisableArbTex();
	
	int w = ofGetWidth();
	int h = ofGetHeight();
	
	// CREATE TEXTURE FOR FBO
	// ----------------------
	glEnable(GL_TEXTURE_2D); eglGetError();
	glGenTextures(1, &tex);  eglGetError();
	glActiveTexture(GL_TEXTURE0); eglGetError();
	glBindTexture(GL_TEXTURE_2D, tex);  eglGetError();
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); eglGetError();
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); eglGetError();
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); eglGetError();
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); eglGetError();
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, w, h, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);  eglGetError();
	
	
	// CREATE FBO
	// -----------
	glGenFramebuffers(1, &fbo); eglGetError();
	glBindFramebuffer(GL_FRAMEBUFFER, fbo); eglGetError();
	
	// .. fbo with depth attachment.
	glGenRenderbuffers(1, &rbo_depth); eglGetError();
	glBindRenderbuffer(GL_RENDERBUFFER, rbo_depth); eglGetError();
	glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, w, h); eglGetError();
	glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, rbo_depth); eglGetError();
	
	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, tex, 0); eglGetError();
		
	if(glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
		printf("Incomplete fbo.\n");
		::exit(0);
	}
	
	eglCheckFramebufferStatus();
	glBindFramebuffer(GL_FRAMEBUFFER, 0); eglGetError();
	glBindRenderbuffer(GL_RENDERBUFFER, 0); eglGetError();
	glBindTexture(GL_TEXTURE_2D, 0);
}

//--------------------------------------------------------------
void testApp::update(){
		
}

// Just draws a quad which we "capture" in a texture
void testApp::drawScene() {
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	gluPerspective(45.0f, float(ofGetWidth())/ofGetHeight(), 0.1, 100);

	glMatrixMode(GL_TEXTURE);
	glLoadIdentity();
	
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	glTranslatef(0,0,-10);
	
	float s = 4;			
	glColor3f(1,0,1); eglGetError();
	glBegin(GL_QUADS); 
		glVertex2f(-s,s);
		glVertex2f(s,s); 
		glVertex2f(s,-s);
		glVertex2f(-s,-s); 
	glEnd(); 
	
	glPointSize(10.0f);
	glColor3f(0,1,0);
	glBegin(GL_POINTS);
		glVertex3f(0.5,0,-1);
	glEnd();
	glColor3f(1,1,1);
	eglGetError();
}

//--------------------------------------------------------------
void testApp::draw(){
	// DRAW INTO FBO
	int w = ofGetWidth();
	int h = ofGetHeight();


	// DRAW INTO TEXTURE USING FBO
	// ---------------------------
	glEnable(GL_TEXTURE_2D);
	glDisable(GL_BLEND);
	glBindTexture(GL_TEXTURE_2D, 0);
	glEnable(GL_DEPTH_TEST);
	
	glBindFramebuffer(GL_FRAMEBUFFER, fbo); eglGetError();
	glClearColor(1,1,1,1);
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	drawScene();
	
	
	// DRAW TEXTURE WITH CONTENTS OF SCENE (RENDER TO TEXTURE)
	// -------------------------------------------------------
	float s = 256;
	
	glBindFramebuffer(GL_FRAMEBUFFER, 0); eglGetError();
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	
	glMatrixMode(GL_TEXTURE);
	glLoadIdentity();
	
	glMatrixMode(GL_COLOR);
	glLoadIdentity();
	
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	
	glClearColor(1,1,1,1);
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	
	glDisable(GL_DEPTH_TEST);
	glDisable(GL_CULL_FACE);	
	
	glEnable(GL_TEXTURE_2D);
	glActiveTexture(GL_TEXTURE0);
	glBindTexture(GL_TEXTURE_2D, tex); eglGetError();
	glDisable(GL_LIGHTING);
	
	float ww, hh;
	ww = hh = 1.0;
	glBegin(GL_QUADS);
		glTexCoord2f(0,0); glVertex3f(-ww,-hh, -1.0f);
		glTexCoord2f(1,0); glVertex3f(ww,-hh, -1.0f);
		glTexCoord2f(1,1); glVertex3f(ww,hh, -1.0f);
		glTexCoord2f(0,1); glVertex3f(-ww,hh, -1.0f);
	glEnd(); 
	glGetError();

}

//--------------------------------------------------------------
void testApp::keyPressed(int key){

}

//--------------------------------------------------------------
void testApp::keyReleased(int key){

}

//--------------------------------------------------------------
void testApp::mouseMoved(int x, int y){

}

//--------------------------------------------------------------
void testApp::mouseDragged(int x, int y, int button){

}

//--------------------------------------------------------------
void testApp::mousePressed(int x, int y, int button){

}

//--------------------------------------------------------------
void testApp::mouseReleased(int x, int y, int button){

}

//--------------------------------------------------------------
void testApp::windowResized(int w, int h){

}

//--------------------------------------------------------------
void testApp::gotMessage(ofMessage msg){

}

//--------------------------------------------------------------
void testApp::dragEvent(ofDragInfo dragInfo){ 

}