Metal

uv mapping in Metal

• SwiftUI + Metal – Create special effects by building your own shaders - YouTube at 26:07
• What is UV mapping?
  • Essentially UV Mapping is altering the position calculations from absolute pixel values to relative ratio values.

Case study

// Called in SwiftUI using .colorEffect()
[[ stitchable ]] float2 wave(
	float2 position, float time, float2 rect) {
		float2 uv = position / rect; // 👈🏼
		pos.y += sin(time * 5 + position.y / 20) * 5;
		return position;
	}
)

Width	X	UV
100	0	0
100	50	0.5
200	50	0.25