package codechicken.lib.lighting;
import codechicken.lib.render.CCRenderState;
import codechicken.lib.vec.Rotation;
import codechicken.lib.vec.Vector3;
public class LightModel implements CCRenderState.IVertexOperation
{
public static final int operationIndex = CCRenderState.registerOperation();
public static class Light
{
public Vector3 ambient = new Vector3();
public Vector3 diffuse = new Vector3();
public Vector3 position;
public Light(Vector3 pos) {
position = pos.copy().normalize();
}
public Light setDiffuse(Vector3 vec) {
diffuse.set(vec);
return this;
}
public Light setAmbient(Vector3 vec) {
ambient.set(vec);
return this;
}
}
public static LightModel standardLightModel;
static {
standardLightModel = new LightModel()
.setAmbient(new Vector3(0.4, 0.4, 0.4))
.addLight(new Light(new Vector3(0.2, 1, -0.7))
.setDiffuse(new Vector3(0.6, 0.6, 0.6)))
.addLight(new Light(new Vector3(-0.2, 1, 0.7))
.setDiffuse(new Vector3(0.6, 0.6, 0.6)));
}
private Vector3 ambient = new Vector3();
private Light[] lights = new Light[8];
private int lightCount;
public LightModel addLight(Light light) {
lights[lightCount++] = light;
return this;
}
public LightModel setAmbient(Vector3 vec) {
ambient.set(vec);
return this;
}
/**
* @param colour The pre-lighting vertex colour. RGBA format
* @param normal The normal at the vertex
* @return The lighting applied colour
*/
public int apply(int colour, Vector3 normal) {
Vector3 n_colour = ambient.copy();
for (int l = 0; l < lightCount; l++) {
Light light = lights[l];
double n_l = light.position.dotProduct(normal);
double f = n_l > 0 ? 1 : 0;
n_colour.x += light.ambient.x + f * light.diffuse.x * n_l;
n_colour.y += light.ambient.y + f * light.diffuse.y * n_l;
n_colour.z += light.ambient.z + f * light.diffuse.z * n_l;
}
if (n_colour.x > 1)
n_colour.x = 1;
if (n_colour.y > 1)
n_colour.y = 1;
if (n_colour.z > 1)
n_colour.z = 1;
n_colour.multiply((colour >>> 24) / 255D, (colour >> 16 & 0xFF) / 255D, (colour >> 8 & 0xFF) / 255D);
return (int) (n_colour.x * 255) << 24 | (int) (n_colour.y * 255) << 16 | (int) (n_colour.z * 255) << 8 | colour & 0xFF;
}
@Override
public boolean load() {
if(!CCRenderState.computeLighting)
return false;
CCRenderState.pipeline.addDependency(CCRenderState.normalAttrib);
CCRenderState.pipeline.addDependency(CCRenderState.colourAttrib);
return true;
}
@Override
public void operate() {
CCRenderState.setColour(apply(CCRenderState.colour, CCRenderState.normal));
}
@Override
public int operationID() {
return operationIndex;
}
public PlanarLightModel reducePlanar() {
int[] colours = new int[6];
for (int i = 0; i < 6; i++)
colours[i] = apply(-1, Rotation.axes[i]);
return new PlanarLightModel(colours);
}
}