render: create a node for sub render graphs, create a graph init node

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

@@ -123,6 +123,7 @@ pub struct RenderGraph {
     queue: Rc<wgpu::Queue>,
     slots: FxHashMap<RenderGraphLabelValue, ResourcedSlot>,
     nodes: FxHashMap<RenderGraphLabelValue, PassEntry>,
+    sub_graphs: FxHashMap<RenderGraphLabelValue, RenderGraph>,
     bind_groups: FxHashMap<RenderGraphLabelValue, BindGroupEntry>,
     /// A directed graph used to determine dependencies of nodes.
     node_graph: petgraph::matrix_graph::DiMatrix<RenderGraphLabelValue, (), Option<()>, usize>,
@@ -135,6 +136,7 @@ impl RenderGraph {
             queue,
             slots: Default::default(),
             nodes: Default::default(),
+            sub_graphs: Default::default(),
             bind_groups: Default::default(),
             node_graph: Default::default(),
         }
@@ -261,16 +263,27 @@ impl RenderGraph {
 
     #[instrument(skip(self, world))]
     pub fn prepare(&mut self, world: &mut World) {
-        // prepare all passes
         let mut buffer_writes = VecDeque::<GraphBufferWrite>::new();
         // reserve some buffer writes. not all nodes write so half the amount of them is probably
         // fine.
         buffer_writes.reserve(self.nodes.len() / 2);
 
-        for (label, pass) in &mut self.nodes {
-            let mut context = RenderGraphContext::new(&self.device, &self.queue, None, label.clone());
-            let mut inner = pass.inner.borrow_mut();
-            inner.prepare(world, &mut context);
+        let mut sorted: VecDeque<RenderGraphLabelValue> = petgraph::algo::toposort(&self.node_graph, None)
+            .expect("RenderGraph had cycled!")
+            .iter()
+            .map(|i| self.node_graph[i.clone()].clone())
+            .collect();
+
+        while let Some(pass_label) = sorted.pop_front() {
+            let pass = self.nodes.get(&pass_label).unwrap();
+            let device = self.device.clone();
+            let queue = self.queue.clone();
+
+            let inner = pass.inner.clone();
+            let mut inner = inner.borrow_mut();
+
+            let mut context = RenderGraphContext::new(&device, &queue, None, pass_label.clone());
+            inner.prepare(self, world, &mut context);
             buffer_writes.append(&mut context.buffer_writes);
         }
 
@@ -465,24 +478,33 @@ impl RenderGraph {
             pass.set_bind_group(*index, bg, &[]);
         }
     }
+
+    pub fn sub_graph_mut<L: Into<RenderGraphLabelValue>>(&mut self, label: L) -> Option<&mut RenderGraph> {
+        self.sub_graphs.get_mut(&label.into())
+    }
 }
 
-impl Node for RenderGraph {
+pub struct SubGraphNode(RenderGraphLabelValue);
+
+impl Node for SubGraphNode {
     fn desc<'a, 'b>(&'a mut self, _: &'b mut RenderGraph) -> NodeDesc {
-        // TODO: how would bind groups be shared between sub-graphs?
         NodeDesc::new(NodeType::Graph, None, vec![])
     }
 
-    fn prepare(&mut self, world: &mut World, _: &mut RenderGraphContext) {
-        self.prepare(world);
+    fn prepare(&mut self, graph: &mut RenderGraph, world: &mut World, _: &mut RenderGraphContext) {
+        let sg = graph.sub_graph_mut(self.0.clone())
+            .unwrap_or_else(|| panic!("failed to find sub graph for SubGraphNode: {:?}", self.0));
+        sg.prepare(world);
     }
 
     fn execute(
         &mut self,
-        _: &mut RenderGraph,
+        graph: &mut RenderGraph,
         _: &NodeDesc,
         _: &mut RenderGraphContext,
     ) {
-        self.render();
+        let sg = graph.sub_graph_mut(self.0.clone())
+            .unwrap_or_else(|| panic!("failed to find sub graph for SubGraphNode: {:?}", self.0));
+        sg.render();
     }
-}
+}

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

@@ -351,7 +351,7 @@ pub trait Node: 'static {
     /// 
     /// This phase runs before `execute` and is meant to be used to collect data from the World
     /// and write to GPU buffers.
-    fn prepare(&mut self, world: &mut World, context: &mut RenderGraphContext);
+    fn prepare(&mut self, graph: &mut RenderGraph, world: &mut World, context: &mut RenderGraphContext);
     
     /// Execute the node.
     /// 

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

@@ -9,8 +9,7 @@ use crate::{
     render::{
         camera::{CameraUniform, RenderCamera},
         graph::{
-            RenderGraphContext, Node, NodeDesc, NodeSlot,
-            NodeType, RenderTarget, SlotAttribute, SlotType, SlotValue,
+            Node, NodeDesc, NodeSlot, NodeType, RenderGraph, RenderGraphContext, RenderTarget, SlotAttribute, SlotType, SlotValue
         },
         render_buffer::BufferWrapper, texture::RenderTexture,
     },
@@ -147,7 +146,7 @@ impl Node for BasePass {
         desc
     }
 
-    fn prepare(&mut self, world: &mut lyra_ecs::World, context: &mut RenderGraphContext) {
+    fn prepare(&mut self, _graph: &mut RenderGraph, world: &mut lyra_ecs::World, context: &mut RenderGraphContext) {
         if let Some(camera) = world.view_iter::<&mut CameraComponent>().next() {
             let mut render_cam =
                 RenderCamera::new(PhysicalSize::new(self.screen_size.x, self.screen_size.y));

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

@@ -0,0 +1,33 @@
+use lyra_game_derive::RenderGraphLabel;
+
+use crate::render::graph::{Node, NodeDesc, NodeSlot, NodeType};
+
+#[derive(Debug, Default, Clone, Copy, Hash, RenderGraphLabel)]
+pub struct InitNodeLabel;
+
+pub struct InitNode {
+    slots: Vec<NodeSlot>,
+}
+
+impl Node for InitNode {
+    fn desc<'a, 'b>(&'a mut self, _: &'b mut crate::render::graph::RenderGraph) -> crate::render::graph::NodeDesc {
+        let mut desc = NodeDesc::new(NodeType::Node, None, vec![]);
+        // the slots can just be cloned since the slot attribute doesn't really matter much.
+        desc.slots = self.slots.clone();
+
+        desc
+    }
+
+    fn prepare(&mut self, _: &mut crate::render::graph::RenderGraph, _: &mut lyra_ecs::World, _: &mut crate::render::graph::RenderGraphContext) {
+        
+    }
+
+    fn execute(
+        &mut self,
+        _: &mut crate::render::graph::RenderGraph,
+        _: &crate::render::graph::NodeDesc,
+        _: &mut crate::render::graph::RenderGraphContext,
+    ) {
+        
+    }
+}

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

@@ -2,8 +2,7 @@ use lyra_game_derive::RenderGraphLabel;
 
 use crate::render::{
     graph::{
-        RenderGraphContext, Node, NodeDesc, NodeType, SlotAttribute,
-        SlotValue,
+        Node, NodeDesc, NodeType, RenderGraph, RenderGraphContext, SlotAttribute, SlotValue
     },
     light::LightUniformBuffers,
 };
@@ -58,7 +57,7 @@ impl Node for LightBasePass {
         desc
     }
 
-    fn prepare(&mut self, world: &mut lyra_ecs::World, context: &mut RenderGraphContext) {
+    fn prepare(&mut self, _graph: &mut RenderGraph, world: &mut lyra_ecs::World, context: &mut RenderGraphContext) {
         let tick = world.current_tick();
         let lights = self.light_buffers.as_mut().unwrap();
         lights.update_lights(context.queue, tick, world);

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

@@ -7,7 +7,7 @@ use wgpu::util::DeviceExt;
 
 use crate::render::{
     graph::{
-        Node, NodeDesc, NodeType, RenderGraphContext, SlotAttribute, SlotValue
+        Node, NodeDesc, NodeType, RenderGraph, RenderGraphContext, SlotAttribute, SlotValue
     }, renderer::ScreenSize, resource::{ComputePipelineDescriptor, PipelineDescriptor, Shader}
 };
 
@@ -215,7 +215,7 @@ impl Node for LightCullComputePass {
         desc
     }
 
-    fn prepare(&mut self, world: &mut World, context: &mut RenderGraphContext) {
+    fn prepare(&mut self, _graph: &mut RenderGraph, world: &mut World, context: &mut RenderGraphContext) {
         context.queue_buffer_write_with(LightCullComputePassSlots::IndexCounterBuffer, 0, 0);
 
         let screen_size  = world.get_resource::<ScreenSize>();

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

@@ -15,8 +15,7 @@ use wgpu::util::DeviceExt;
 use crate::{
     render::{
         desc_buf_lay::DescVertexBufferLayout, graph::{
-            RenderGraphContext, Node, NodeDesc,
-            NodeType,
+            Node, NodeDesc, NodeType, RenderGraph, RenderGraphContext
         }, material::{Material, MaterialUniform}, render_buffer::{BufferStorage, BufferWrapper}, render_job::RenderJob, resource::{FragmentState, PipelineDescriptor, RenderPipelineDescriptor, Shader, VertexState}, texture::RenderTexture, transform_buffer_storage::{TransformBuffers, TransformGroup}, vertex::Vertex
     },
     DeltaTime,
@@ -297,8 +296,8 @@ impl Node for MeshPass {
         desc
     }
 
-    #[instrument(skip(self, world, context))]
-    fn prepare(&mut self, world: &mut lyra_ecs::World, context: &mut RenderGraphContext) {
+    #[instrument(skip(self, _graph, world, context))]
+    fn prepare(&mut self, _graph: &mut RenderGraph, world: &mut lyra_ecs::World, context: &mut RenderGraphContext) {
         let device = context.device;
         let queue = context.queue;
         let render_limits = device.limits();

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

@@ -11,4 +11,7 @@ mod light_base;
 pub use light_base::*;
 
 mod present_pass;
-pub use present_pass::*;
+pub use present_pass::*;
+
+mod init;
+pub use init::*;

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

@@ -2,7 +2,7 @@ use std::hash::Hash;
 
 use lyra_game_derive::RenderGraphLabel;
 
-use crate::render::graph::{RenderGraphContext, RenderGraphLabel, RenderGraphLabelValue, Node, NodeDesc, NodeSlot, NodeType, SlotAttribute, SlotType};
+use crate::render::graph::{Node, NodeDesc, NodeSlot, NodeType, RenderGraph, RenderGraphContext, RenderGraphLabel, RenderGraphLabelValue, SlotAttribute, SlotType};
 
 #[derive(Debug, Clone, Hash, PartialEq, RenderGraphLabel)]
 pub struct PresentPassLabel(RenderGraphLabelValue);
@@ -50,7 +50,7 @@ impl Node for PresentPass {
         desc
     }
 
-    fn prepare(&mut self, _world: &mut lyra_ecs::World, _context: &mut RenderGraphContext) {
+    fn prepare(&mut self, _graph: &mut RenderGraph, _world: &mut lyra_ecs::World, _context: &mut RenderGraphContext) {
         
     }