Implement proper sun intersection.

src/main/java/dev/thatredox/chunkynative/common/export/primitives/PackedSun.java

@@ -4,39 +4,48 @@
 import dev.thatredox.chunkynative.common.export.Packer;
 import it.unimi.dsi.fastutil.ints.IntArrayList;
 import se.llbit.chunky.renderer.scene.sky.Sun;
+import se.llbit.math.ColorUtil;
 
 public class PackedSun implements Packer {
     public final int flags;
     public final long texture;
     public final float intensity;
     public final float altitude;
     public final float azimuth;
+    public final float luminosity;
+    public final int sunColor;
 
     public PackedSun(Sun sun, AbstractTextureLoader texturePalette) {
         flags = sun.drawTexture() ? 1 : 0;
         texture = texturePalette.get(Sun.texture).get();
         intensity = (float) sun.getIntensity();
         altitude = (float) sun.getAltitude();
         azimuth = (float) sun.getAzimuth();
+        luminosity = (float) sun.getLuminosity();
+        sunColor = ColorUtil.getRGB(sun.getColor());
     }
 
     /**
-     * Pack the sun into 6 ints.
+     * Pack the sun into 8 ints.
      * 0: Flags. 1 if the sun should be drawn. 0 if not.
      * 1 & 2: Sun texture reference.
      * 3: float sun intensity
      * 4: float sun altitude
      * 5: float sun azimuth
+     * 6: float sun luminosity
+     * 7: Sun color in (A)RGB
      */
     @Override
     public IntArrayList pack() {
-        IntArrayList out = new IntArrayList(6);
+        IntArrayList out = new IntArrayList(8);
         out.add(flags);
         out.add((int) (texture >>> 32));
         out.add((int) texture);
         out.add(Float.floatToIntBits(intensity));
         out.add(Float.floatToIntBits(altitude));
         out.add(Float.floatToIntBits(azimuth));
+        out.add(Float.floatToIntBits(luminosity));
+        out.add(sunColor);
         return out;
     }
 }

src/main/opencl/kernel/include/sky.h

@@ -5,15 +5,18 @@
 #include "rt.h"
 #include "textureAtlas.h"
 #include "random.h"
+#include "material.h"
 
 typedef struct {
     int flags;
     int textureSize;
     int texture;
     float intensity;
+    float luminosity;
     float3 su;
     float3 sv;
     float3 sw;
+    float4 color;
 } Sun;
 
 Sun Sun_new(__global const int* data) {
@@ -22,6 +25,8 @@ Sun Sun_new(__global const int* data) {
     sun.textureSize = data[1];
     sun.texture = data[2];
     sun.intensity = as_float(data[3]);
+    sun.luminosity = as_float(data[6]);
+    sun.color = colorFromArgb(data[7]);
 
     float phi = as_float(data[4]);
     float theta = as_float(data[5]);
@@ -54,10 +59,16 @@ bool Sun_intersect(Sun self, image2d_array_t atlas, Ray ray, MaterialSample* sam
     if (a >= 0 && a < width2) {
         float b = M_PI_2_F - acos(dot(direction, self.sv)) + width;
         if (b >= 0 && b < width2) {
-            float4 color = Atlas_read_uv(a / width2, b / width2, 
-                                         self.texture, self.textureSize, atlas);
-            color *= self.intensity;
-            sample->color += color;
+            if (ray.flags & RAY_INDIRECT) {
+                float4 color = self.color;
+                color *= self.luminosity;
+                sample->color += color;
+            } else {
+                float4 color = Atlas_read_uv(a / width2, b / width2,
+                                             self.texture, self.textureSize, atlas);
+                color *= self.intensity;
+                sample->color += color;
+            }
             return true;
         }
     }