shadows

src/shaders/raycasting.cginc

@@ -5,7 +5,7 @@
 *   incAxis: Last axis that was used to increment position
 *   addr: Number given by node, brick offset in brick array
 */
-vec4 castBricks(vec3 origin, vec3 start, vec3 dir, vec3 incAxis, uint addr)
+HitResult castBricks(vec3 origin, vec3 start, vec3 dir, vec3 incAxis, uint addr)
 {
     vec3 o = origin;
 
@@ -34,7 +34,7 @@ vec4 castBricks(vec3 origin, vec3 start, vec3 dir, vec3 incAxis, uint addr)
 
             // Normal vector (negate previous increment axis and mult by sign)
             vec3 normal = -incAxis * raySign;
-            return vec4(solve(hitPoint, dir, normal, brick-1), 1.0);
+            return HitResult(brick-1, hitPoint, normal);
         }
 
         // Get new closest axis to increment
@@ -47,14 +47,14 @@ vec4 castBricks(vec3 origin, vec3 start, vec3 dir, vec3 incAxis, uint addr)
         if(pos.x > 31 || pos.y > 31 || pos.z > 31) { break; }
     }
 
-    return vec4(1.0,0.0,0.5,0.0);
+    return HitResult(0, vec3(0,0,0), vec3(0,0,0));
 }
 
 /*
 *   origin: Camera position
 *   dir: Ray coming from camera position going through currently drawn pixel
 */
-vec3 castNodes(vec3 origin, vec3 dir)
+HitResult castNodes(vec3 origin, vec3 dir)
 {
     // Round input pos to nearest voxel
     vec3 pos = floor(origin);
@@ -81,8 +81,8 @@ vec3 castNodes(vec3 origin, vec3 dir)
             vec3 hitPoint = origin + dir * len;
             
             // Cast brick
-            vec4 result = castBricks(pos, hitPoint, dir, incAxis, node);
-            if(result.a > 0.0) return result.rgb;
+            HitResult result = castBricks(pos, hitPoint, dir, incAxis, node);
+            if(result.data > 0) return result;
         }
 
         // Get new closest axis to increment
@@ -96,5 +96,5 @@ vec3 castNodes(vec3 origin, vec3 dir)
     }
 
     // Not found
-    return vec3(0.0, 0.0, 0.0);
+    return HitResult(0, vec3(0,0,0), vec3(0,0,0));
 }

src/shaders/shader.frag

@@ -13,6 +13,7 @@ layout(set=0,binding=0) uniform Uniforms {
     mat4 _ViewMatrix;
     mat4 _ProjMatrixInv;
     vec3 _CamPos;
+    vec3 _SunDir;
     float _Time;
 };
 layout(set=1,binding=0) uniform usampler3D _NodesTexture;
@@ -27,16 +28,27 @@ layout(set=3, binding=0) uniform Materials {
 // #define NEAR 0.01
 
 // Include
+#include "structs.cginc"
 #include "shading.cginc"
 #include "raycasting.cginc"
 
 
 void main() 
 {
+    // Black by default
+    out_color = vec4(0,0,0,1);
+
     // Calculate ray direction
     vec3 view_dir = (_ProjMatrixInv * vec4(vert_uv, 0, 1)).xyz;
     vec3 ray_dir = normalize(_ViewMatrix * vec4(view_dir,0)).xyz;
 
     // Raycast
-    out_color = vec4(castNodes(_CamPos, ray_dir), 1.0);
+    HitResult primary = castNodes(_CamPos, ray_dir);
+    if(primary.data > 0)
+    {
+        out_color = vec4(applyLighting(primary.pos, ray_dir, primary.normal, primary.data), 1.0);
+
+        HitResult shadow = castNodes(primary.pos-ray_dir*0.000001, _SunDir);
+        if(shadow.data > 0) out_color *= 0.1;
+    }
 }

src/shaders/shading.cginc

@@ -3,15 +3,14 @@
     view: View vector (camera ray)
     normal: Normal vector
 */
-vec3 solve(vec3 hitPoint, vec3 view, vec3 normal, uint brick)
+vec3 applyLighting(vec3 hitPoint, vec3 view, vec3 normal, uint brick)
 {
     // Lighting
     vec3 light_color = vec3(1.0, 1.0, 1.0);
-    vec3 light_dir = normalize(hitPoint-vec3(0.0, 1.5, 4.0));
 
     vec3 ambient = light_color * 0.1;
-    vec3 diffuse = light_color * max(1.0-dot(normal, light_dir), 0.0);
-    vec3 specular = light_color * pow(max(dot(view, reflect(-light_dir, normal)), 0.0), 32);
+    vec3 diffuse = light_color * max(1.0-dot(normal, _SunDir), 0.0);
+    vec3 specular = light_color * pow(max(dot(view, reflect(-_SunDir, normal)), 0.0), 32);
 
     // Combine colors
     vec3 object_color = _Materials[brick].albedo.rgb;//vec3(0.0, 0.1, 0.5);

src/shaders/structs.cginc

@@ -0,0 +1,6 @@
+
+struct HitResult {
+    uint data; // Voxel data
+    vec3 pos; // Position in world
+    vec3 normal; // Normal vector
+};