Update vulkan example

Example now renders in 3D using the tracked HMD position and
shows cubes at the location of each hand controller.

openxr/Cargo.toml

@@ -28,6 +28,13 @@ libloading = { version = "0.7", optional = true }
 [dev-dependencies]
 ash = "0.31"
 ctrlc = "3.1.5"
+cgmath = { version = "0.18", features = ["mint"] }
+# We can't have a dev dependency with the same name as a feature
+mint_dev = { package = "mint", version = "0.5" }
+
+[[example]]
+name = "vulkan"
+required-features = ["mint"]
 
 [target.'cfg(windows)'.dependencies]
 winapi = { version = "0.3", features = ["profileapi"] }

openxr/examples/debug_pattern.frag

@@ -1,9 +1,9 @@
 #version 450
 #extension GL_EXT_multiview : require
 
-layout(location = 0) in vec2 screen_coords;
+layout(location = 1) in vec3 vColor;
 layout(location = 0) out vec4 color;
 
 void main() {
-    color = vec4(screen_coords, gl_ViewIndex, 1);
+    color = vec4(vColor.r, (cos(vColor.gb * 4) + 1)/2.0, 1);
 }

openxr/examples/transform.vert

@@ -0,0 +1,26 @@
+#version 450
+#extension GL_EXT_multiview : require
+
+layout(location = 0) in vec3 vPosition;
+
+layout(location = 0) out vec2 screen_coords;
+layout(location = 1) out vec3 vColor;
+
+layout(push_constant) uniform ModelTransform {
+    mat4 model;
+};
+
+struct Transform {
+    mat4 view_project;
+};
+
+layout(binding = 0) uniform Transforms {
+    Transform transform[2];
+};
+
+void main()  {
+    vec4 world_pos = model * vec4(vPosition, 1.0);
+    vec4 pos = transform[gl_ViewIndex].view_project * world_pos;
+    gl_Position = pos;
+    vColor = vec3(gl_VertexIndex/10.0, world_pos.gb);
+}