rez_demo/sources/GL_STUFF/EFFECTS/ReelManager.cpp

/*
#include <GL/glew.h>
*/
#include <GLES2/gl2.h>
#include "ReelManager.h"
#include <vector>

/* equals stdlib.h from C */
#include <cstdlib>

ReelManager::ReelManager(unsigned int textureNumber, unsigned int width, unsigned int height) {
	TEXTURE_NUM = textureNumber;
	textures = (GLuint*) malloc(TEXTURE_NUM * sizeof(GLuint));
	glGenFramebuffers(1, &FBO);
	glGenTextures(TEXTURE_NUM, textures);
	for (int i = 0; i < TEXTURE_NUM; i++) {
		glActiveTexture(GL_TEXTURE0);
		glBindTexture(GL_TEXTURE_2D, textures[i]);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, 0);
	}
	glBindTexture(GL_TEXTURE_2D, 0);
}

void ReelManager::nextTexture() {
	currentIndex = ++currentIndex % TEXTURE_NUM;
	glBindFramebuffer(GL_FRAMEBUFFER, FBO);
	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, textures[currentIndex], 0);
	glBindFramebuffer(GL_FRAMEBUFFER, 0);
}

void ReelManager::clearTexture() {
	glBindFramebuffer(GL_FRAMEBUFFER, FBO);
	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, textures[currentIndex], 0);
	glClearColor(0.0, 0.0, 0.0, 0.0);
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	glBindFramebuffer(GL_FRAMEBUFFER, 0);
}

GLuint ReelManager::getFBO() {
	return FBO;
}

std::vector<GLuint> ReelManager::getTextures() {
	std::vector<GLuint> vec = std::vector<GLuint>();
	for (int i = currentIndex + 1 ; i < TEXTURE_NUM; i++) {
		vec.push_back(textures[i]);
	}
	for (int i = 0; i <= currentIndex; i++) {
		vec.push_back(textures[i]);
	}
	return vec;
}