should be testing with '<=' so that we also draw edge pixels

'< 0' gives us pixels inside the triangle. '== 0' gives us pixels on
the edges of the triangle

ggdt/src/graphics/bitmap/triangles.rs

@@ -57,7 +57,7 @@ pub fn per_pixel_triangle_2d<PixelType: Pixel>(
 		for pixel in row_pixels.iter_mut() {
 			// note that for a counter-clockwise vertex winding order with the direction of Y+ going down instead
 			// of up, we need to test for *negative* area when checking if we're inside the triangle
-			if w0 < 0.0 && w1 < 0.0 && w2 < 0.0 {
+			if w0 <= 0.0 && w1 <= 0.0 && w2 <= 0.0 {
 				pixel_fn(pixel, w0, w1, w2);
 			}