}
private void initProgram(){
Shader spriteVS = loadShader("res/shader/sprite_vs.glsl" , GL4.GL_VERTEX_SHADER);
Shader spriteFS = loadShader("res/shader/sprite_hue_fs.glsl", GL4.GL_FRAGMENT_SHADER);
this.defaultProgram = new ShaderProgram(spriteVS, spriteFS);
this.defaultProgram.linkProgram(this.gl);
}