render: implement view target chains for post processing steps

lyra-game/Cargo.toml

@@ -12,7 +12,7 @@ lyra-math = { path = "../lyra-math" }
 lyra-scene = { path = "../lyra-scene" }
 
 winit = "0.28.1"
-wgpu = "0.15.1"
+wgpu = { version = "0.15.1", features = [ "expose-ids"] }
 
 tracing = "0.1.37"
 tracing-subscriber = { version = "0.3.16", features = [ "tracing-log" ] }

lyra-game/src/render/graph/passes/base.rs

@@ -135,7 +135,7 @@ impl Node for BasePass {
     ) {
         let mut vt = graph.view_target_mut();
         vt.primary.create_frame();
-        vt.next_chain(context.encoder.as_mut().unwrap());
+        //vt.next_chain();
         vt.primary.create_frame_view();
         /* debug_assert!(
             !rt.current_texture.is_some(),

lyra-game/src/render/graph/passes/mod.rs

@@ -16,5 +16,5 @@ pub use present_pass::*;
 mod init;
 pub use init::*;
 
-/* mod tint;
+mod tint;
-pub use tint::*; */
+pub use tint::*;

lyra-game/src/render/graph/passes/present_pass.rs

@@ -32,7 +32,8 @@ impl Node for PresentPass {
         
     }
 
-    fn execute(&mut self, graph: &mut crate::render::graph::RenderGraph, _desc: &crate::render::graph::NodeDesc, context: &mut crate::render::graph::RenderGraphContext) {        let mut vt = graph.view_target_mut();
+    fn execute(&mut self, graph: &mut crate::render::graph::RenderGraph, _desc: &crate::render::graph::NodeDesc, context: &mut crate::render::graph::RenderGraphContext) {
+        let mut vt = graph.view_target_mut();
         vt.copy_to_primary(context.encoder.as_mut().unwrap());
         context.submit_encoder();
 

lyra-game/src/render/graph/passes/tint.rs

@@ -1,35 +1,34 @@
-use std::{cell::RefCell, rc::Rc};
+use std::{collections::HashMap, rc::Rc};
 
 use lyra_game_derive::RenderGraphLabel;
 
 use crate::render::{
-    graph::{Node, NodeDesc, NodeSlot, NodeType, RenderTarget, SlotAttribute, SlotType, SlotValue},
+    graph::{Node, NodeDesc, NodeType},
     resource::{FragmentState, PipelineDescriptor, RenderPipelineDescriptor, Shader, VertexState},
 };
 
-use super::BasePassSlots;
-
 #[derive(Debug, Clone, Copy, Hash, RenderGraphLabel)]
 pub enum TintPassSlots {
     InputRenderTarget,
     InputTextureView,
 
     TextureViewBindGroup,
-    Frame
+    Frame,
 }
 
 #[derive(Default, Debug, Clone, Copy, Hash, RenderGraphLabel)]
 pub struct TintPassLabel;
 
+#[derive(Debug, Default)]
 pub struct TintPass {
-    render_target: Option<RenderTarget>,
+    target_sampler: Option<wgpu::Sampler>,
+    bgl: Option<Rc<wgpu::BindGroupLayout>>,
+    bg_cache: HashMap<wgpu::Id, wgpu::BindGroup>,
 }
 
 impl TintPass {
-    pub fn new(render_target: RenderTarget) -> Self {
+    pub fn new() -> Self {
-        Self {
+        Self::default()
-            render_target: Some(render_target)
-        }
     }
 }
 
@@ -40,14 +39,6 @@ impl Node for TintPass {
     ) -> crate::render::graph::NodeDesc {
         let device = &graph.device;
 
-        // get surface config format
-        /* let main_rt = graph
-            .slot_value(BasePassSlots::MainRenderTarget)
-            .and_then(|s| s.as_render_target())
-            .expect("missing main render target");
-        let surface_config_format = main_rt.format();
-        drop(main_rt); */
-
         let bgl = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
             label: Some("tint_bgl"),
             entries: &[
@@ -70,27 +61,16 @@ impl Node for TintPass {
             ],
         });
         let bgl = Rc::new(bgl);
-
+        self.bgl = Some(bgl.clone());
-        let input_view = graph
+        self.target_sampler = Some(device.create_sampler(&wgpu::SamplerDescriptor::default()));
-            .slot_value(BasePassSlots::WindowTextureView)
-            .and_then(|s| s.as_texture_view())
-            .expect("missing input texture view");
-
-        let bg = device.create_bind_group(&wgpu::BindGroupDescriptor {
-            label: Some("tint_bg"),
-            layout: &*bgl,
-            entries: &[wgpu::BindGroupEntry {
-                binding: 0,
-                resource: wgpu::BindingResource::TextureView(input_view),
-            }],
-        });
 
         let shader = Rc::new(Shader {
             label: Some("tint_shader".into()),
             source: include_str!("../../shaders/tint.wgsl").to_string(),
         });
 
-        let mut desc = NodeDesc::new(
+        let vt = graph.view_target();
+        let desc = NodeDesc::new(
             NodeType::Render,
             Some(PipelineDescriptor::Render(RenderPipelineDescriptor {
                 label: Some("tint_pass".into()),
@@ -105,7 +85,7 @@ impl Node for TintPass {
                     module: shader,
                     entry_point: "fs_main".into(),
                     targets: vec![Some(wgpu::ColorTargetState {
-                        format: self.render_target.as_ref().unwrap().format(),
+                        format: vt.format(),
                         blend: Some(wgpu::BlendState::REPLACE),
                         write_mask: wgpu::ColorWrites::ALL,
                     })],
@@ -115,22 +95,9 @@ impl Node for TintPass {
                 multisample: wgpu::MultisampleState::default(),
                 multiview: None,
             })),
-            vec![(&TintPassSlots::TextureViewBindGroup, bg.into(), Some(bgl))],
+            vec![],
         );
 
-        // desc.add_buffer_slot(
-        //     FxaaPassSlots::Lights,
-        //     SlotAttribute::Output,
-        //     Some(SlotValue::Buffer(light_buffers.buffer.clone())),
-        // );
-
-        desc.add_slot(NodeSlot {
-            ty: SlotType::Frame,
-            attribute: SlotAttribute::Output,
-            label: TintPassSlots::Frame.into(),
-            value: Some(SlotValue::Lazy),
-        });
-
         desc
     }
 
@@ -149,31 +116,45 @@ impl Node for TintPass {
         _: &crate::render::graph::NodeDesc,
         context: &mut crate::render::graph::RenderGraphContext,
     ) {
-        let rt = self.render_target.as_ref().unwrap();
+        let pipeline = graph
-        let frame = rt.create_frame();
+            .pipeline(context.label.clone())
+            .expect("Failed to find pipeline for MeshPass");
 
-        let view = frame.texture()
+        let mut vt = graph.view_target_mut();
-            .create_view(&wgpu::TextureViewDescriptor::default());
+        let chain = vt.get_chain();
+        let source_view = chain.source.frame_view.as_ref().unwrap();
+        let dest_view = chain.dest.frame_view.as_ref().unwrap();
 
-        let frame_slot = graph
+        let bg = self
-            .slot_value_mut(TintPassSlots::Frame)
+            .bg_cache
-            .expect("somehow the frame slot is missing");
+            .entry(source_view.global_id())
-        *frame_slot = SlotValue::Frame(Rc::new(RefCell::new(Some(frame))));
+            .or_insert_with(|| {
-
+                graph
-        let bg = graph.bind_group(TintPassSlots::TextureViewBindGroup);
+                    .device()
-
+                    .create_bind_group(&wgpu::BindGroupDescriptor {
-        /* let view = graph
+                        label: Some("tint_bg"),
-            .slot_value(BasePassSlots::WindowTextureView)
+                        layout: self.bgl.as_ref().unwrap(),
-            .unwrap()
+                        entries: &[
-            .as_texture_view()
+                            wgpu::BindGroupEntry {
-            .expect("BasePassSlots::WindowTextureView was not a TextureView slot"); */
+                                binding: 0,
+                                resource: wgpu::BindingResource::TextureView(source_view),
+                            },
+                            wgpu::BindGroupEntry {
+                                binding: 1,
+                                resource: wgpu::BindingResource::Sampler(
+                                    self.target_sampler.as_ref().unwrap(),
+                                ),
+                            },
+                        ],
+                    })
+            });
 
         {
             let encoder = context.encoder.as_mut().unwrap();
             let mut pass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
                 label: Some("tint_pass"),
                 color_attachments: &[Some(wgpu::RenderPassColorAttachment {
-                    view: &view,
+                    view: &dest_view,
                     resolve_target: None,
                     ops: wgpu::Operations {
                         load: wgpu::LoadOp::Load,
@@ -182,9 +163,10 @@ impl Node for TintPass {
                 })],
                 depth_stencil_attachment: None,
             });
+            pass.set_pipeline(&pipeline.as_render());
 
             pass.set_bind_group(0, bg, &[]);
-            pass.draw(0..4, 0..1);
+            pass.draw(0..3, 0..1);
         }
     }
 }

lyra-game/src/render/graph/render_target.rs

@@ -1,5 +1,7 @@
 use std::sync::Arc;
 
+use tracing::debug;
+
 use crate::math;
 
 enum RenderTargetInner {
@@ -187,39 +189,29 @@ impl FrameTarget {
     }
 }
 
-pub struct TargetViewChain {
+//struct TargetViewChainPrimary
-    source: FrameTarget,
+
-    dest: FrameTarget,
+pub struct TargetViewChain<'a> {
+    pub source: &'a mut FrameTarget,
+    pub dest: &'a mut FrameTarget,
 }
 
-impl TargetViewChain {
+struct ViewChain {
-    pub fn next(&mut self, encoder: &mut wgpu::CommandEncoder) {
+    source: FrameTarget,
-        let size = self.source.size();
+    dest: FrameTarget,
-        let size = wgpu::Extent3d {
+    /// tracks the target that is currently being presented
-            width: size.x,
+    active: u8,
-            height: size.y,
+}
-            depth_or_array_layers: 1,
-        };
 
-        let source_tex = self.source.frame.as_ref().unwrap().texture();
+impl ViewChain {
-        let dest_tex = self.dest.frame.as_ref().unwrap().texture();
+    fn active(&self) -> &FrameTarget {
-
+        if self.active == 0 {
-        let source_ict = wgpu::ImageCopyTexture {
+            &self.source
-            texture: source_tex,
+        } else if self.active == 1 {
-            mip_level: 0,
+            &self.dest
-            origin: wgpu::Origin3d::ZERO,
+        } else {
-            aspect: wgpu::TextureAspect::All,
+            panic!("active chain index became invalid! ({})", self.active);
-        };
+        }
-
-        let dest_ict = wgpu::ImageCopyTexture {
-            texture: dest_tex,
-            mip_level: 0,
-            origin: wgpu::Origin3d::ZERO,
-            aspect: wgpu::TextureAspect::All,
-        };
-
-        encoder.copy_texture_to_texture(source_ict, dest_ict, size);
-        std::mem::swap(&mut self.source, &mut self.dest);
     }
 }
 
@@ -227,16 +219,19 @@ pub struct ViewTarget {
     device: Arc<wgpu::Device>,
     /// The primary RenderTarget, likely a Surface
     pub primary: FrameTarget,
-    pub chain: Option<TargetViewChain>,
+    chain: Option<ViewChain>,
 }
 
 impl ViewTarget {
     pub fn new(device: Arc<wgpu::Device>, primary: RenderTarget) -> Self {
-        Self {
+        let mut s = Self {
             device,
             primary: FrameTarget::new(primary),
-            chain: None
+            chain: None,
-        }
+        };
+
+        s.create_chain(s.primary.format(), s.primary.size());
+        s
     }
 
     pub fn size(&self) -> math::UVec2 {
@@ -248,15 +243,14 @@ impl ViewTarget {
     }
 
     pub fn resize(&mut self, device: &wgpu::Device, size: math::UVec2) {
+        if size != self.primary.size() {
             self.primary.render_target.resize(device, size);
+            self.create_chain(self.primary.format(), size);
+        }
     }
 
-    /// Cycle the target view chain, storing it in self, and returning a mutable borrow to it.
+    fn create_chain(&mut self, format: wgpu::TextureFormat, size: math::UVec2) {
-    pub fn next_chain(&mut self, encoder: &mut wgpu::CommandEncoder) -> &mut TargetViewChain {
+        debug!("Creating chain with {:?} format and {:?} size", format, size);
-        // TODO: check if chain has already been made. If it has, use next on it.
-        let _ = encoder;
-        let format = self.primary.format();
-        let size = self.primary.size();
         
         let mut source = FrameTarget::new(RenderTarget::new_texture(&self.device, format, size));
         source.create_frame();
@@ -266,36 +260,69 @@ impl ViewTarget {
         dest.create_frame();
         dest.create_frame_view();
 
-        self.chain = Some(TargetViewChain {
+        self.chain = Some(ViewChain {
             source,
             dest,
+            active: 0,
         });
-        //self.reset_chain(encoder);
+    }
-        self.chain.as_mut().unwrap()
+
+    /// Cycle the target view chain, storing it in self, and returning a mutable borrow to it.
+    pub fn get_chain(&mut self) -> TargetViewChain {
+        let format = self.primary.format();
+        let size = self.primary.size();
+
+        if let Some(chain) = &self.chain {
+            // check if the chain needs to be recreated
+            if chain.source.format() != format || chain.source.size() != size {
+                self.create_chain(format, size);
+            }
+        } else {
+            self.create_chain(format, size);
+        }
+
+        let chain = self.chain.as_mut().unwrap();
+
+        if chain.active == 0 {
+            chain.active = 1;
+            TargetViewChain {
+                source: &mut chain.source,
+                dest: &mut chain.dest,
+            }
+        } else if chain.active == 1 {
+            chain.active = 0;
+            TargetViewChain {
+                source: &mut chain.dest,
+                dest: &mut chain.source,
+            }
+        } else {
+            panic!("active chain index became invalid! ({})", chain.active);
+        }
     }
 
     /// Get the [`wgpu::TextureView`] to render to
     pub fn render_view(&self) -> &wgpu::TextureView {
         let chain = self.chain.as_ref().unwrap();
-        chain.source.frame_view.as_ref().unwrap()
+        chain.active().frame_view.as_ref().unwrap()
     }
 
     /// Copy the chain target to the primary target
     /// 
-    /// The primary target must have `wgpu::TextureUsages::COPY_DST`.
+    /// The primary target must have `wgpu::TextureUsages::COPY_DST`. This also resets the active
-    pub fn copy_to_primary(&self, encoder: &mut wgpu::CommandEncoder) {
+    /// chain texture.
-        let chain = self.chain.as_ref().unwrap();
+    pub fn copy_to_primary(&mut self, encoder: &mut wgpu::CommandEncoder) {
-        let chain_tex = chain.source.frame.as_ref().unwrap().texture();
+        let chain = self.chain.as_mut().unwrap();
+        let active_tex = chain.active().frame.as_ref().unwrap().texture();
 
-        let source_ict = wgpu::ImageCopyTexture {
+        let active_copy = wgpu::ImageCopyTexture {
-            texture: chain_tex,
+            texture: active_tex,
             mip_level: 0,
             origin: wgpu::Origin3d::ZERO,
             aspect: wgpu::TextureAspect::All,
         };
 
         let dest_tex = self.primary.frame.as_ref().unwrap().texture();
-        let dest_ict = wgpu::ImageCopyTexture {
+        let dest_copy = wgpu::ImageCopyTexture {
             texture: dest_tex,
             mip_level: 0,
             origin: wgpu::Origin3d::ZERO,
@@ -309,6 +336,11 @@ impl ViewTarget {
             depth_or_array_layers: 1,
         };
 
-        encoder.copy_texture_to_texture(source_ict, dest_ict, size);
+        encoder.copy_texture_to_texture(active_copy, dest_copy, size);
+        
+        // reset active texture after a render
+        // must get the chain again because of the borrow checker
+        let chain = self.chain.as_mut().unwrap();
+        chain.active = 0;
     }
 }

lyra-game/src/render/renderer.rs

@@ -9,7 +9,7 @@ use lyra_game_derive::RenderGraphLabel;
 use tracing::{debug, instrument, warn};
 use winit::window::Window;
 
-use crate::render::graph::{BasePass, BasePassLabel, BasePassSlots, LightBasePass, LightBasePassLabel, LightCullComputePass, LightCullComputePassLabel, MeshPass, MeshesPassLabel, PresentPass, PresentPassLabel, RenderGraphLabelValue, RenderTarget, SubGraphNode, ViewTarget};
+use crate::render::graph::{BasePass, BasePassLabel, BasePassSlots, LightBasePass, LightBasePassLabel, LightCullComputePass, LightCullComputePassLabel, MeshPass, MeshesPassLabel, PresentPass, PresentPassLabel, RenderGraphLabelValue, RenderTarget, SubGraphNode, TintPass, TintPassLabel, ViewTarget};
 
 use super::graph::RenderGraph;
 use super::{resource::RenderPipeline, render_job::RenderJob};
@@ -164,6 +164,9 @@ impl BasicRenderer {
             ));
         }
 
+        main_graph.add_node(TintPassLabel, TintPass::default());
+        main_graph.add_edge(TestSubGraphLabel, TintPassLabel);
+
         //let present_pass_label = PresentPassLabel::new(BasePassSlots::Frame);//TintPassSlots::Frame);
         let p = PresentPass::default();
         main_graph.add_node(PresentPassLabel, p);

lyra-game/src/render/shaders/tint.wgsl

@@ -4,28 +4,29 @@ var t_screen: texture_2d<f32>;
 var s_screen: sampler;
 
 struct VertexOutput {
-    @builtin(position) clip_position: vec4<f32>,
+    @builtin(position)
-    @location(0) tex_coords: vec2<f32>,
+    clip_position: vec4<f32>,
+    @location(0)
+    tex_coords: vec2<f32>,
 }
 
 @vertex
 fn vs_main(
     @builtin(vertex_index) vertex_index: u32,
 ) -> VertexOutput {
+    let tex_coords = vec2<f32>(f32(vertex_index >> 1u), f32(vertex_index & 1u)) * 2.0;
+    let clip_position = vec4<f32>(tex_coords * vec2<f32>(2.0, -2.0) + vec2<f32>(-1.0, 1.0), 0.0, 1.0);
 
-    const vertices = array<vec4<f32>, 4>(vec4<f32>(-1.0, -1.0, 0.0, 1.0), vec4<f32>(1.0, -1.0, 0.0, 1.0), vec4<f32>(-1.0, 1.0, 0.0, 1.0), vec4<f32>(1.0, 1.0, 0.0, 1.0));
+    return VertexOutput(clip_position, tex_coords);
-    const tex_coords = array<vec2<f32>, 4>(vec2<f32>(0.0, 0.0), vec2<f32>(1.0, 0.0), vec2<f32>(0.0, 1.0), vec2<f32>(1.0, 1.0));
-    
-    var out: VertexOutput;
-    out.clip_position = vertices[vertex_index];
-    out.tex_coords = tex_coords[vertex_index];
-
-    return out;
 }
 
 @fragment
 fn fs_main(in: VertexOutput) -> @location(0) vec4<f32> {
-    let rgb: vec3<f32> = textureSample(t_screen, s_screen, in.tex_coords).xyz;
+    let resolution = vec2<f32>(textureDimensions(t_screen));
-    rgb *= vec3<f32>(0.8);
+    let inverse_screen_size = 1.0 / resolution.xy;
+    let tex_coords = in.clip_position.xy * inverse_screen_size;
+
+    var rgb: vec3<f32> = textureSample(t_screen, s_screen, tex_coords).xyz;
+    rgb *= vec3<f32>(1.0, 0.2, 0.2);
     return vec4<f32>(rgb, 1.0);
 }