diff --git a/include/rasteriser/rasteriser.h b/include/rasteriser/rasteriser.h
index 1d9a20f..94ec488 100644
--- a/include/rasteriser/rasteriser.h
+++ b/include/rasteriser/rasteriser.h
@@ -21,14 +21,12 @@ typedef struct {
   f32 h0;
   f32 h1;
   f32 h2;
+  colour_t colour;
 } triangle_t;
 
-void draw_wireframe_triangle(window_t *wnd, Arena *arena, triangle_t triangle,
-                             colour_t colour);
-void draw_filled_triangle(window_t *wnd, Arena *arena, triangle_t triangle,
-                          colour_t colour);
-void draw_shaded_triangle(window_t *wnd, Arena *arena, triangle_t triangle,
-                          colour_t colour);
+void draw_wireframe_triangle(window_t *wnd, Arena *arena, triangle_t triangle);
+void draw_filled_triangle(window_t *wnd, Arena *arena, triangle_t triangle);
+void draw_shaded_triangle(window_t *wnd, Arena *arena, triangle_t triangle);
 void draw_line(window_t *wnd, Arena *arena, line_t line, colour_t colour);
 
 #endif // !RASTERISER_H
diff --git a/src/rasteriser/rasteriser.c b/src/rasteriser/rasteriser.c
index cb404ed..e1c07b4 100644
--- a/src/rasteriser/rasteriser.c
+++ b/src/rasteriser/rasteriser.c
@@ -16,17 +16,15 @@ internal list_float_t *interpolate(Arena *arena, i32 i0, f32 d0, i32 i1,
 
 internal inline void order_triangle_points(triangle_t *triangle);
 
-void draw_wireframe_triangle(window_t *wnd, Arena *arena, triangle_t triangle,
-                             colour_t colour) {
+void draw_wireframe_triangle(window_t *wnd, Arena *arena, triangle_t triangle) {
   order_triangle_points(&triangle);
 
-  draw_line(wnd, arena, (line_t){triangle.p0, triangle.p1}, colour);
-  draw_line(wnd, arena, (line_t){triangle.p1, triangle.p2}, colour);
-  draw_line(wnd, arena, (line_t){triangle.p2, triangle.p0}, colour);
+  draw_line(wnd, arena, (line_t){triangle.p0, triangle.p1}, triangle.colour);
+  draw_line(wnd, arena, (line_t){triangle.p1, triangle.p2}, triangle.colour);
+  draw_line(wnd, arena, (line_t){triangle.p2, triangle.p0}, triangle.colour);
 }
 
-void draw_filled_triangle(window_t *wnd, Arena *arena, triangle_t triangle,
-                          colour_t colour) {
+void draw_filled_triangle(window_t *wnd, Arena *arena, triangle_t triangle) {
   order_triangle_points(&triangle);
 
   i32 x0 = triangle.p0.x;
@@ -59,13 +57,12 @@ void draw_filled_triangle(window_t *wnd, Arena *arena, triangle_t triangle,
     i32 index = y - y0;
     for (i64 x = (i64)list_get(x_left, index); x < list_get(x_right, index);
          ++x) {
-      set_pixel(wnd, x, y, colour);
+      set_pixel(wnd, x, y, triangle.colour);
     }
   }
 }
 
-void draw_shaded_triangle(window_t *wnd, Arena *arena, triangle_t triangle,
-                          colour_t colour) {
+void draw_shaded_triangle(window_t *wnd, Arena *arena, triangle_t triangle) {
   order_triangle_points(&triangle);
 
   i32 x0 = triangle.p0.x;
@@ -124,7 +121,7 @@ void draw_shaded_triangle(window_t *wnd, Arena *arena, triangle_t triangle,
     for (i64 x = xl; x < xr; ++x) {
       h_segment = interpolate(arena, xl, list_get(h_left, index), xr,
                               list_get(h_right, index));
-      shaded_colour = colour_mul(colour, list_get(h_segment, x - xl));
+      shaded_colour = colour_mul(triangle.colour, list_get(h_segment, x - xl));
       set_pixel(wnd, x, y, shaded_colour);
     }
   }