stubbed out shaders

buffer.cpp

@@ -4,6 +4,7 @@
 
 #include "datatypes.cpp"
 #include "helpers.cpp"
+#include "shaders/shader.cpp"
 
 namespace UwU {
       // Buffer object - can be a wayland surface or a virtual buffer
@@ -42,5 +43,21 @@ namespace UwU {
             pixels[i + 3] = 0xff; // A
             return;
         }
+
+        void drawPixelShader(Coord2 coord, Shader shader) {
+            size_t i = (size_t)coord.y * stride + (size_t)coord.x * 4;
+            uint8_t b0 = pixels[i + 0];
+            uint8_t g0 = pixels[i + 1];
+            uint8_t r0 = pixels[i + 2];
+            Color newColor = shader.color();
+            uint8_t b = Helpers::lerp8(b0, newColor.b, newColor.a);
+            uint8_t g = Helpers::lerp8(g0, newColor.g, newColor.a);
+            uint8_t r = Helpers::lerp8(r0, newColor.r, newColor.a);
+            pixels[i + 0] = b;    // B
+            pixels[i + 1] = g;    // G
+            pixels[i + 2] = r;    // R
+            pixels[i + 3] = 0xff; // A
+            return;
+        }
   };
 }