public void draw(float[] matrix) {
heightmapProgram.useProgram();
heightmapProgram.setUniforms(matrix);
bindData();
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBuffer.getBufferId());
glDrawElements(GL_TRIANGLES, numElements, GL_UNSIGNED_SHORT, 0);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
}
public void bindData() {
vertexBuffer.setVertexAttribPointer(
0, heightmapProgram.getPositionAttributeLocation(), POSITION_COMPONENT_COUNT, 0);
}