import java.awt.Color;

/**
 * Simple shader that just copy the interpolated color to the screen,
 * taking the depth of the fragment into acount.
 * 
 * @author: cdehais
 */
public class TextureShader extends Shader {

    DepthBuffer depth;
    Texture texture;
    boolean combineWithBaseColor;

    public TextureShader(GraphicsWrapper screen) {
        super(screen);
        depth = new DepthBuffer(screen.getWidth(), screen.getHeight());
        texture = null;
    }

    public void setTexture(String path) {
        try {
            texture = new Texture(path);
        } catch (Exception e) {
            System.out.println("Could not load texture " + path);
            e.printStackTrace();
            texture = null;
        }
    }

    public void setCombineWithBaseColor(boolean combineWithBaseColor) {
        this.combineWithBaseColor = combineWithBaseColor;
    }

    public void shade(Fragment fragment) {
        if (depth.testFragment(fragment)) {
            /* The Fragment may not have texture coordinates */
            try {
                double u = fragment.getAttribute(7) % 1;
                double v = fragment.getAttribute(8) % 1;

                Color couleur = texture.sample(u, v);
                screen.setPixel(fragment.getX(), fragment.getY(), couleur);

            } catch (ArrayIndexOutOfBoundsException e) {
                screen.setPixel(fragment.getX(), fragment.getY(), fragment.getColor());
            }
            depth.writeFragment(fragment);
        }
    }

    public void reset() {
        depth.clear();
    }
}