charcoal/OpenGLEngine/MyBatch.cpp

#include "MyBatch.h"

void MyBatch::setup_element_buffers()
{
	glBindBuffer(GL_ARRAY_BUFFER, m_element_buffers[0]);
	// TODO: Maybe make the next line use a typedef instead of MyShaderProgram::ColorType
	glBufferData(GL_ARRAY_BUFFER, m_elements.size() * sizeof(MyBatchTestShaderProgram::ColorType), NULL, GL_STREAM_DRAW);
}

void MyBatch::setup_vao()
{
	glBindBuffer(GL_ARRAY_BUFFER, m_vertex_vbo);
	glEnableVertexAttribArray(0);
	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, NULL);
	glBindBuffer(GL_ARRAY_BUFFER, m_element_buffers[0]);
	glEnableVertexAttribArray(1);
	glVertexAttribPointer(1, 4, GL_FLOAT, GL_FALSE, 0, NULL);

	glVertexAttribDivisor(0, 0); // Only need to send the mesh data once
	glVertexAttribDivisor(1, 1); // Send the color data for each instance drawn
}

void MyBatch::update_element_buffers()
{
	// TODO: There are probably better ways to do this. Should check with the old engine to see what I did there.
	glBindBuffer(GL_ARRAY_BUFFER, m_element_buffers[0]);
	glBufferData(GL_ARRAY_BUFFER, m_elements.size() * sizeof(MyBatchTestShaderProgram::ColorType), NULL, GL_STREAM_DRAW);
	glBufferSubData(GL_ARRAY_BUFFER, 0, m_elements.size() * sizeof(MyBatchTestShaderProgram::ColorType), m_elements.data());
}