examples: created gkurve example

examples/gkurve/vert.wgsl

@@ -0,0 +1,22 @@
+struct VertexUniform {
+    matrix: mat4x4<f32>,
+}
+@binding(0) @group(0) var<uniform> ubos : array<VertexUniform, 3>;
+
+struct VertexOut {
+     @builtin(position) position_clip : vec4<f32>,
+     @location(0) frag_uv : vec2<f32>,
+     @interpolate(flat) @location(1) instance_index: u32,
+}
+
+@stage(vertex) fn main(
+    @builtin(instance_index) instanceIdx : u32,
+    @location(0) position: vec4<f32>,
+    @location(1) uv: vec2<f32>,
+) -> VertexOut {
+     var output : VertexOut;
+     output.position_clip = ubos[instanceIdx].matrix * position;
+     output.frag_uv = uv;
+     output.instance_index = instanceIdx;
+     return output;
+}