optimized faces

Shaders/shader.vert

@@ -1,17 +1,12 @@
 #version 430 core
 
-    struct FaceData {
-        uint x;
-        uint y;
-        uint z;
-        uint facing; // 0=+X,1=-X,2=+Y,3=-Y,4=+Z,5=-Z
-        uint texture;
-        uint lightLevel;
-    };
+struct FaceData {
+    uint pack; // All data in 4 bytes
+};
 
-    layout(std430, binding = 0) buffer FaceBuffer {
-        uint faces[];
-    };
+layout(std430, binding = 0) buffer FaceBuffer {
+    uint faces[];
+};
 
 uniform mat4 view;
 uniform mat4 projection;
@@ -77,23 +72,35 @@ const vec3 offsets[6][6] = vec3[6][6](
 
 const vec2 uvs[6] = vec2[6](vec2(0,0), vec2(1,1), vec2(1,0), vec2(1,1), vec2(0,0), vec2(0,1));
 
+// Function to unpack the 4-byte face data
+// Bit layout from C# (little-endian, but we read as uint):
+// Bits 31-24: Y (8 bits) 0-255
+// Bits 23-20: Z (4 bits) 0-15  
+// Bits 19-16: X (4 bits) 0-15
+// Bits 15-10: Texture (6 bits) 0-63
+// Bits 9-7:   Facing (3 bits) 0-7
+// Bits 6-3:   Light (4 bits) 0-15
+// Bits 2-0:   unused (3 bits)
+void unpackFace(uint pack, out uint x, out uint y, out uint z, 
+                out uint facing, out uint texture, out uint lightLevel)
+{
+    y = (pack >> 24) & 0xFFu;        // Y: bits 24-31 (8 bits)
+    z = (pack >> 20) & 0x0Fu;        // Z: bits 20-23 (4 bits)
+    x = (pack >> 16) & 0x0Fu;        // X: bits 16-19 (4 bits)
+    texture = (pack >> 10) & 0x3Fu;  // Texture: bits 10-15 (6 bits)
+    facing = (pack >> 7) & 0x07u;    // Facing: bits 7-9 (3 bits)
+    lightLevel = (pack >> 3) & 0x0Fu;// Light: bits 3-6 (4 bits)
+}
+
 void main()
 {
     uint faceIndex = gl_VertexID / 6u;
     uint vertIndex = gl_VertexID % 6u;
 
-    uint start = faceIndex * 2u; // 2 uint per face
-     
-    uint u0 = faces[start]; // data in uint 0
-    uint u1 = faces[start + 1]; // data in uint 1
+    uint pack = faces[faceIndex];
 
-    // extract values from bits
-    uint x = u0 & 0xFFu;
-    uint y = (u0 >> 8) & 0xFFu;
-    uint z = (u0 >> 16) & 0xFFu;
-    uint facing = (u0 >> 24) & 0xFFu;
-    uint texture = u1 & 0xFFu;
-    uint lightLevel = (u1 >> 8) & 0xFFu;
+    uint x, y, z, facing, texture, lightLevel;
+    unpackFace(pack, x, y, z, facing, texture, lightLevel);
 
     vec3 basePos = vec3(x, y, z) + vec3(chunkX, 0, chunkY) * 16.0;