--wip-- [skip ci]

src/fullscreen.vert.glsl

@@ -11,7 +11,7 @@ const vec2 full_screen_triangle[3] = {
     };
 
 void main() {
-    vec2 tri = (full_screen_triangle[gl_VertexIndex] * 2.0) - 1.0;
+    vec2 tri = (full_screen_triangle[gl_VertexIndex - gl_BaseVertex] * 2.0) - 1.0;
     v_pos = tri;
-    gl_Position = vec4(v_pos, 0.5, 1.0);
+    gl_Position = vec4(v_pos, gl_BaseVertex / 65536.0 , 1.0);
 }

src/include.glsl

@@ -6,6 +6,7 @@ layout(push_constant) uniform PushConstantData {
     vec3 dimensions;
     vec3 lowest_corner;
     uint enable[16];
+    float material;
 } pc;
 
 layout(set = 0, binding = 0) uniform Lights {

src/main.rs

@@ -47,7 +47,10 @@ use vulkano::{
         QueueCreateInfo, QueueFlags, physical::PhysicalDeviceType,
     },
     format::Format,
-    image::{Image, ImageCreateInfo, ImageType, ImageUsage, SampleCount, view::ImageView},
+    image::{
+        Image, ImageCreateInfo, ImageType, ImageUsage, SampleCount,
+        view::{ImageView, ImageViewCreateInfo},
+    },
     instance::{Instance, InstanceCreateInfo, InstanceExtensions},
     memory::allocator::{
         AllocationCreateInfo, MemoryAllocatePreference, MemoryTypeFilter, StandardMemoryAllocator,
@@ -59,7 +62,7 @@ use vulkano::{
         graphics::{
             GraphicsPipelineCreateInfo,
             color_blend::{ColorBlendAttachmentState, ColorBlendState},
-            depth_stencil::{DepthState, DepthStencilState},
+            depth_stencil::{CompareOp, DepthState, DepthStencilState},
             input_assembly::InputAssemblyState,
             multisample::MultisampleState,
             rasterization::{CullMode, FrontFace, PolygonMode, RasterizationState},
@@ -211,6 +214,8 @@ struct RenderContext {
     render_pass: Arc<RenderPass>,
     framebuffers: Vec<Arc<Framebuffer>>,
     color_buffer: Arc<ImageView>,
+    material_colour_buffer: Arc<ImageView>,
+    material_depth_buffer: Arc<ImageView>,
     normal_buffer: Arc<ImageView>,
     depth_buffer: Arc<ImageView>,
     shader_modules: ShaderModules,
@@ -512,6 +517,7 @@ impl App {
                     geometry_shader: true,
                     maintenance4: true,
                     fill_mode_non_solid: true,
+                    shader_draw_parameters: true,
                     ..DeviceFeatures::empty()
                 },
                 ..Default::default()
@@ -781,6 +787,18 @@ impl ApplicationHandler for App {
                     load_op: Clear,
                     store_op: Store,
                 },
+                material_as_colour: {
+                    format: Format::R16_UNORM,
+                    samples: 1,
+                    load_op: Clear,
+                    store_op: DontCare,
+                },
+                material_as_depth: {
+                    format: Format::D,
+                    samples: 1,
+                    load_op: Load,
+                    store_op: DontCare,
+                },
                 color: {
                     format: Format::A2B10G10R10_UNORM_PACK32,
                     samples: 1,
@@ -801,13 +819,13 @@ impl ApplicationHandler for App {
                 },
             },
             passes: [{
-                color: [],
+                color: [material_as_colour],
                 depth_stencil: {depth},
                 input: [],
             },
             {
                 color: [color, normals],
-                depth_stencil: {},
+                depth_stencil: {material_as_depth},
                 input: [depth],
             },
             {
@@ -829,8 +847,14 @@ impl ApplicationHandler for App {
             depth_range: 0.0..=1.0,
         };
 
-        let (framebuffers, color_buffer, normal_buffer, depth_buffer) =
+        let (
-            framebuffer_generation(&images, &render_pass, &self.memory_allocator);
+            framebuffers,
+            color_buffer,
+            material_colour_buffer,
+            material_depth_buffer,
+            normal_buffer,
+            depth_buffer,
+        ) = framebuffer_generation(&images, &render_pass, &self.memory_allocator);
 
         let lighting_pipeline = pipeline_recompile(
             &render_pass,
@@ -862,6 +886,8 @@ impl ApplicationHandler for App {
             render_pass,
             framebuffers,
             color_buffer,
+            material_colour_buffer,
+            material_depth_buffer,
             normal_buffer,
             depth_buffer,
             shader_modules,
@@ -1031,6 +1057,8 @@ impl App {
             (
                 rcx.framebuffers,
                 rcx.color_buffer,
+                rcx.material_colour_buffer,
+                rcx.material_depth_buffer,
                 rcx.normal_buffer,
                 rcx.depth_buffer,
             ) = framebuffer_generation(&new_images, &rcx.render_pass, &self.memory_allocator);
@@ -1174,6 +1202,7 @@ impl App {
                 dimensions:    Vec3::ONE.to_array().into(),
                 lowest_corner: Vec3::ZERO.into(),
                 enable:        [0; 16],
+                material:      0.,
             };
 
             let uniform_data = implicit_vs::Camera {
@@ -1504,6 +1533,8 @@ fn framebuffer_generation(
     Arc<ImageView>,
     Arc<ImageView>,
     Arc<ImageView>,
+    Arc<ImageView>,
+    Arc<ImageView>,
 ) {
     let depth_buffer = ImageView::new_default(
         Image::new(
@@ -1541,6 +1572,41 @@ fn framebuffer_generation(
     )
     .unwrap();
 
+    let material_image = Image::new(
+        allocator.clone(),
+        ImageCreateInfo {
+            image_type: ImageType::Dim2d,
+            format: Format::D16_UNORM,
+            extent: images[0].extent(),
+            usage: ImageUsage::COLOR_ATTACHMENT
+                | ImageUsage::DEPTH_STENCIL_ATTACHMENT
+                | ImageUsage::TRANSIENT_ATTACHMENT,
+            ..Default::default()
+        },
+        AllocationCreateInfo::default(),
+    )
+    .unwrap();
+
+    let material_colour_buffer = ImageView::new(
+        material_image.clone(),
+        ImageViewCreateInfo {
+            format: Format::R16_UNORM,
+            usage: ImageUsage::COLOR_ATTACHMENT | ImageUsage::TRANSIENT_ATTACHMENT,
+            ..ImageViewCreateInfo::from_image(&material_image)
+        },
+    )
+    .unwrap();
+
+    let material_depth_buffer = ImageView::new(
+        material_image.clone(),
+        ImageViewCreateInfo {
+            format: Format::D16_UNORM,
+            usage: ImageUsage::DEPTH_STENCIL_ATTACHMENT | ImageUsage::TRANSIENT_ATTACHMENT,
+            ..ImageViewCreateInfo::from_image(&material_image)
+        },
+    )
+    .unwrap();
+
     let normal_buffer = ImageView::new_default(
         Image::new(
             allocator.clone(),
@@ -1568,6 +1634,8 @@ fn framebuffer_generation(
                 FramebufferCreateInfo {
                     attachments: vec![
                         view,
+                        material_colour_buffer.clone(),
+                        material_depth_buffer.clone(),
                         color_buffer.clone(),
                         normal_buffer.clone(),
                         depth_buffer.clone(),
@@ -1579,7 +1647,14 @@ fn framebuffer_generation(
         })
         .collect::<Vec<_>>();
 
-    (framebuffers, color_buffer, normal_buffer, depth_buffer)
+    (
+        framebuffers,
+        color_buffer,
+        material_colour_buffer,
+        material_depth_buffer,
+        normal_buffer,
+        depth_buffer,
+    )
 }
 
 fn get_spec_constants(debug: &PreviousDebug) -> HashMap<u32, SpecializationConstant> {
@@ -1714,7 +1789,10 @@ fn deferred_pipelines_recompile(
                         ..Default::default()
                     }),
                     multisample_state: Some(MultisampleState::default()),
-                    color_blend_state: None,
+                    color_blend_state: Some(ColorBlendState::with_attachment_states(
+                        deferred_subpass.num_color_attachments(),
+                        ColorBlendAttachmentState::default(),
+                    )),
                     subpass: Some(deferred_subpass.into()),
                     ..GraphicsPipelineCreateInfo::layout(layout.clone())
                 },
@@ -1778,7 +1856,13 @@ fn deferred_pipelines_recompile(
                         polygon_mode: PolygonMode::Fill,
                         ..RasterizationState::default()
                     }),
-                    depth_stencil_state: None,
+                    depth_stencil_state: Some(DepthStencilState {
+                        depth: Some(DepthState {
+                            write_enable: false,
+                            compare_op:   CompareOp::Equal,
+                        }),
+                        ..Default::default()
+                    }),
                     multisample_state: Some(MultisampleState::default()),
                     color_blend_state: Some(ColorBlendState::with_attachment_states(
                         normals_subpass.num_color_attachments(),

src/trace.frag.glsl

@@ -8,6 +8,8 @@ layout(location = 0) in vec4 pos;
 
 layout(depth_greater) out float gl_FragDepth;
 
+layout(location = 0) out float material;
+
 float scene(vec3 p) {
     return length(p) - 1.0;
 }
@@ -44,6 +46,7 @@ void main() {
     {
         vec4 tpoint = camera_uniforms.proj * camera_uniforms.view * pc.world * vec4(p, 1);
         gl_FragDepth = (tpoint.z / tpoint.w);
+        material = pc.material;
     }
     else
     {