fixed depth buffering for images

resources/examples/vulkan_example.rs

@@ -200,6 +200,8 @@ void main() {
         .viewports_dynamic_scissors_irrelevant(1)
         // See `vertex_shader`.
         .fragment_shader(fs.main_entry_point(), ())
+
+        .depth_stencil_simple_depth()
         // We have to indicate which subpass of which render pass this pipeline is going to be used
         // in. The pipeline will only be usable from this particular subpass.
         .render_pass(Subpass::from(render_pass.clone(), 0).unwrap())

resources/shaders/simple_image.fragment

@@ -2,7 +2,7 @@
 // SIMPLE TEXTURE : FRAGMENT SHADER
 
 // These come in from the previous shader (vertex)
-layout(location = 0) in vec2 position;
+layout(location = 0) in vec2 image_position;
 
 // This goes out to the bound image in window_size_dependent setup
 layout(location = 0) out vec4 f_color;
@@ -15,7 +15,7 @@ void main() {
 
     ivec2 pos = ivec2(gl_FragCoord.x, gl_FragCoord.y);
 
-    f_color = imageLoad(img, ivec2(position)) / (255.0);
+    f_color = imageLoad(img, ivec2(image_position)) / (255.0);
 
     float gamma = 0.5;
     f_color.rgb = pow(f_color.rgb, vec3(1.0/gamma));