Rebuild from scratch with a new strategy using compute shaders and SDF.

src/shaders/display.wgsl

@@ -0,0 +1,27 @@
+struct Uniforms {
+    pan: vec2f,
+    zoom: f32,
+}
+struct TileParams {
+    lod: u32,
+    tile_size: f32,
+    world_min: vec2f,
+    world_max: vec2f,
+}
+
+@group(0) @binding(0) var<uniform> uniforms: Uniforms;
+@group(0) @binding(1) var<uniform> tile_params: TileParams;
+
+@vertex fn vs_main(@builtin(vertex_index) vertex_index : u32) -> @builtin(position) vec4f {
+  const pos = array(
+    vec2( 0.0,  0.5),
+    vec2(-0.5, -0.5),
+    vec2( 0.5, -0.5)
+  );
+
+  return vec4f(pos[vertex_index], 0, 1);
+}
+
+@fragment fn fs_main() -> @location(0) vec4f {
+  return vec4(1, 0, 0, 1);
+}