Fetching WebGPU shaders. Created my first bona fide pipeline. The vertex shader compares the built-in vertex index and the numRows/numColumns uniforms to produce a grid of quads with no vertex or index buffer whatsoever!

shaders/rainPass.frag.wgsl

@@ -0,0 +1,3 @@
+[[stage(fragment)]] fn main([[location(0)]] UV : vec2<f32>) -> [[location(0)]] vec4<f32> {
+	return vec4<f32>(0.0, UV, 1.0);
+}

shaders/rainPass.vert.wgsl

@@ -0,0 +1,39 @@
+[[block]] struct Uniforms {
+	numColumns: i32;
+	numRows: i32;
+};
+[[binding(0), group(0)]] var<uniform> uniforms : Uniforms;
+
+struct VertexOutput {
+	[[builtin(position)]] Position : vec4<f32>;
+	[[location(0)]] UV : vec2<f32>;
+};
+
+[[stage(vertex)]] fn main([[builtin(vertex_index)]] VertexIndex : u32) -> VertexOutput {
+
+	var i = i32(VertexIndex);
+	var quadIndex = i / 6;
+
+	var cornerPosition = vec2<f32>(
+		f32(i % 2),
+		f32(((i + 1) % 6 / 3))
+	);
+
+	var x = uniforms.numColumns;
+
+	var position = cornerPosition;
+	position = position + vec2<f32>(
+		f32(quadIndex % uniforms.numColumns),
+		f32(quadIndex / uniforms.numColumns)
+	);
+	position = position / vec2<f32>(
+		f32(uniforms.numColumns),
+		f32(uniforms.numRows)
+	);
+	position = position * 2.0 - 1.0;
+
+	return VertexOutput(
+		vec4<f32>(position, 1.0, 1.0),
+		cornerPosition
+	);
+}