RenderQuad.cpp

#include "RenderQuad.h"
#include <iostream>

RenderQuad::RenderQuad() {
	GLfloat data[] = {
		-1.0f, 1.0f, 0.0f, 1.0f,
		-1.0f, -1.0f, 0.0f, 0.0f,
		1.0f, -1.0f, 1.0f, 0.0f,
		1.0f, -1.0f, 1.0f, 0.0f,
		1.0f, 1.0f, 1.0f, 1.0f,
		-1.0f, 1.0f, 0.0f, 1.0f
	};

	glGenVertexArrays(1, &vao);
	glGenBuffers(1, &vbo);

	glBindVertexArray(vao);

	// Bind to the first VBO. We will use it to store the vertices.
	glBindBuffer(GL_ARRAY_BUFFER, vbo);
	glBufferData(GL_ARRAY_BUFFER, sizeof(GLfloat) * 6 * 4,
		data, GL_STATIC_DRAW);

	glEnableVertexAttribArray(0);
	glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(GLfloat), 0);

	glEnableVertexAttribArray(1);
	glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(GLfloat), (GLvoid*)(2 * sizeof(GLfloat)));

	// Unbind from the VBOs.
	glBindBuffer(GL_ARRAY_BUFFER, 0);
	// Unbind from the VAO.
	glBindVertexArray(0);
}

RenderQuad::~RenderQuad() {
	glDeleteBuffers(1, &vbo);
	glDeleteVertexArrays(1, &vao);
}

//draw the quad to the whole screen
void RenderQuad::draw() {
	glDisable(GL_DEPTH_TEST);
	glBindVertexArray(vao);
	glDrawArrays(GL_TRIANGLES, 0, 6);
	glBindVertexArray(0);
	glEnable(GL_DEPTH_TEST);
}