Merge branch '2-show-triangle-geometry' into 'dev'

Resolve "Show triangle geometry"

See merge request Steins7/iv!2

Cargo.lock

@@ -122,6 +122,15 @@ dependencies = [
  "bitflags",
 ]
 
+[[package]]
+name = "cmake"
+version = "0.1.45"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "eb6210b637171dfba4cda12e579ac6dc73f5165ad56133e5d72ef3131f320855"
+dependencies = [
+ "cc",
+]
+
 [[package]]
 name = "cocoa"
 version = "0.20.2"
@@ -362,6 +371,7 @@ dependencies = [
  "log",
  "num-traits",
  "raw-window-handle",
+ "shaderc",
  "winit",
 ]
 
@@ -755,6 +765,26 @@ version = "1.0.115"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e54c9a88f2da7238af84b5101443f0c0d0a3bbdc455e34a5c9497b1903ed55d5"
 
+[[package]]
+name = "shaderc"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "03f0cb8d1f8667fc9c50d5054be830a117af5f9a15f87c66b72bbca0c2fca484"
+dependencies = [
+ "libc",
+ "shaderc-sys",
+]
+
+[[package]]
+name = "shaderc-sys"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c89175f80244b82f882033a81bd188f87307c4c39b2fe8d0f194314f270bdea9"
+dependencies = [
+ "cmake",
+ "libc",
+]
+
 [[package]]
 name = "slab"
 version = "0.4.2"

Cargo.toml

@@ -14,6 +14,7 @@ gfx-hal = "^0.6.0"
 winit = "^0.22.0"
 raw-window-handle = "^0.3.3"
 num-traits = "^0.2.12"
+shaderc = "^0.7"
 
 [dependencies.gfx-backend-vulkan]
 version = "^0.6.1"

src/controller.rs

@@ -14,7 +14,7 @@ where
     O: Output<W>,
 {
     pipelines: Vec<SubenginePipeline<'a, I, W, O>>,
-    color: [f32; 4],
+    mouse_pos: [f32; 2],
 }
 
 impl<I, W, O> Controller<'_, I, W, O> 
@@ -38,7 +38,7 @@ where
 
         Controller {
             pipelines: pipelines_vec,
-            color: [0.0, 1.0, 1.0, 0.0],
+            mouse_pos: [0.5, 0.5],
         }
     }
 
@@ -48,6 +48,7 @@ where
         use crate::{
             subengine::subengine_controller::SubengineCommand,
             io::Key,
+            utils::Triangle,
         };
 
         let mut input_keys: Vec<Key> = Vec::new(); 
@@ -61,11 +62,10 @@ where
             }
             for input_key in &input_keys {
                 match input_key {
-                    Key::MouseMove{x,y} => self.color = [
+                    Key::MouseMove{x,y} => self.mouse_pos = [
-                        (x/1280.0) as f32,
+                        (x/1280.0 * 2.0 - 1.0) as f32,
-                        (y/720.0) as f32,
+                        (y/720.0 * 2.0 - 1.0) as f32,
-                        ((x/1280.0 + y/720.0)/2.0) as f32,
+                    ],
-                        1.0],
                     Key::Close => return,
                     _ => (),
                 };
@@ -78,13 +78,24 @@ where
                     subengine.wait_for_exec(Duration::from_millis(1)).unwrap();
                 }
             }
+            
+            let triangle = Triangle {
+                points: [self.mouse_pos, [-0.5, 0.5], [-0.5, -0.5]],
+            };
+
+            debug!("Triangle : {:#?}", triangle);
+
             for (renderer, output) in &mut pipeline.renderers {
-                match renderer.draw_clear_frame(output, self.color) {
+            //    match renderer.draw_clear_frame(output, self.color) {
+            //        Err(err) => warn!("{}", err),
+            //        _ => (),
+            //    }
+                match renderer.draw_triangle_frame(output, triangle) {
                     Err(err) => warn!("{}", err),
                     _ => (),
-                }
+                };
-            }
+            };
-        }
+        };
     }
 }
 //These tests are disabled because of some stange issue with cargo not waiting for the drop 

src/renderer.rs

@@ -9,13 +9,18 @@ use std::{
 
 use crate::{
     io::Output,
+    utils::Triangle,
+    
 };
 
 mod gpu;
-use gpu::Gpu;
+use self::gpu::Gpu;
 
 mod swap_system;
-use swap_system::SwapSystem;
+use self::swap_system::SwapSystem;
+
+mod pipeline;
+use self::pipeline::Pipeline;
 
 //--Renderer implementation-------------------------------------------------------------------------
 #[derive(Debug)]
@@ -23,6 +28,7 @@ pub struct Renderer<B: gfx_hal::Backend> {
     instance: ManuallyDrop<B::Instance>,
     gpu: ManuallyDrop<Gpu<B>>,
     swap_systems: Vec<SwapSystem<B>>,
+    pipelines: Vec<Pipeline<B>>,
 }
 
 impl<B> Drop for Renderer<B>
@@ -35,16 +41,17 @@ where
             device::Device,
         };
 
+        debug!("Dropping Pipelines...");
+        for pipeline in self.pipelines.drain(..) {
+            pipeline.drop(&mut self.gpu);
+        }
+
         debug!("Waiting for device to idle...");
         let _ = self.gpu
             .device()
             .wait_idle();
 
         info!("Dropping Renderer..."); 
-        
-//        for mut pipeline in self.pipelines.drain(..) {
-//        }
-//
         unsafe {
             for mut swap_system in self.swap_systems.drain(..) {
                 self.instance.destroy_surface(swap_system.drop(&mut self.gpu));
@@ -79,12 +86,15 @@ where
                 .map(|surface| SwapSystem::new(&mut gpu, surface))
                 .collect::<Result<Vec<_>,  &str>>()?
         };
+        let pipelines = vec!(Pipeline::new(&mut gpu, &swap_systems[0]) //TODO improve that
+            .map_err(|err| err)?);
 
         debug!("Renderer created !");
         Ok( Renderer {
             instance: ManuallyDrop::new(instance),
             gpu: ManuallyDrop::new(gpu),
             swap_systems,
+            pipelines,
         })
     }
 
@@ -171,5 +181,103 @@ where
 
         Ok(())
     }
+
+    pub fn draw_triangle_frame<W, O>(&mut self, output: &RefCell<O>, triangle: Triangle)
+        -> Result<(), &'static str> 
+    where
+        W: raw_window_handle::HasRawWindowHandle,
+        O: Output<W>,
+    {
+        use gfx_hal::{
+            window::AcquireError,
+            device::Device,
+            queue::Submission,
+        };
+
+        let swap_system = &mut self.swap_systems[output.borrow_mut().get_id()];
+
+        let mut frame = match swap_system.acquire_frame(&self.gpu) {
+            Ok(frame) => frame,
+            Err(err) => match err {
+                AcquireError::NotReady => {
+                    return Err("Frame acquisition failed because all Frames are in use");
+                },
+                AcquireError::OutOfDate => {
+                    swap_system.recreate(&mut self.gpu)?;
+                    debug!("SwapSystem : {:#?}", swap_system);
+                    return Ok(());
+                },
+                _ => Err("Could not acquire Frame from SwapSystem")?,
+        }};
+
+        trace!("Waiting for Frame...");
+        unsafe {
+            let _ = self.gpu.device()
+                .wait_for_fence(&frame.fences[0], !0)
+                .map_err(|_| "Failed to wait for Fence")?;
+            let _ = self.gpu.device()
+                .reset_fence(&frame.fences[0])
+                .map_err(|_| "Failed to reset fence")?;
+        }
+
+        trace!("Uploading triangle data...");
+        let points = triangle.points_flat();
+        self.pipelines[0].write_vertex_buffer(&self.gpu, 0, (&points).to_vec())?; //TODO meh
+
+        trace!("Recording CommandBuffer...");
+        unsafe {
+            use gfx_hal::command::{
+                CommandBufferFlags, 
+                SubpassContents, 
+                ClearValue, 
+                ClearColor,
+                CommandBuffer,
+            };
+
+            frame.command_buffer.begin_primary(CommandBufferFlags::ONE_TIME_SUBMIT);
+
+            const TRIANGLE_CLEAR: ClearValue = 
+                ClearValue {color : ClearColor{float32 : [0.1, 0.2, 0.3, 1.0]}};
+
+            frame.command_buffer.begin_render_pass(
+                &swap_system.render_pass,
+                &frame.framebuffer.as_ref().unwrap(),
+                swap_system.render_area,
+                iter::once(TRIANGLE_CLEAR),
+                SubpassContents::Inline,
+            );
+            frame.command_buffer.bind_graphics_pipeline(self.pipelines[0].raw_pipeline());
+
+            // storing const data via the CommandBuffer
+            //let buffer_ref: &B::Buffer = &self.buffer;
+            //let buffers: Vec<[_; 1]> = vec![(buffer_ref, 0)].into();
+            frame.command_buffer.bind_vertex_buffers(0, self.pipelines[0].raw_vertex_buffers());
+
+            frame.command_buffer.draw(0..3, 0..1);
+            frame.command_buffer.end_render_pass();
+            frame.command_buffer.finish();
+        }
+
+        trace!("Submiting to queue...");
+        let submission = Submission {
+            command_buffers: iter::once(&*frame.command_buffer),
+            wait_semaphores: None,
+            signal_semaphores: iter::once(&frame.signal_semaphores[0]),
+        };
+
+        unsafe {
+            use gfx_hal::queue::CommandQueue;
+
+            self.gpu.queue_mut().submit(submission, Some(&frame.fences[0]));
+        }
+
+        let result = swap_system.present_frame(frame, &mut self.gpu);
+        if result.is_err() {
+            swap_system.recreate(&mut self.gpu).unwrap();
+        }
+
+        Ok(())
+
+    }
 }
  

src/renderer/pipeline.rs

@@ -1,20 +1,309 @@
 #[allow(unused_imports)]
 use log::{debug, error, info, trace, warn};
 
-use std::{
+use std::mem::{ManuallyDrop, size_of};
-    mem::ManuallyDrop,
+
+use gfx_hal::{
+    buffer::SubRange,
 };
 
+use super::{
+    gpu::Gpu,
+    swap_system::SwapSystem,
+};
+
+mod attachement;
+use self::attachement::Attachement;
+
+const VERTEX_SOURCE: &str = 
+"#version 440 core
+
+layout (location = 0) in vec2 position;
+
+out gl_PerVertex {
+    vec4 gl_Position;
+};
+
+void main()
+{
+    gl_Position = vec4(position, 0.0, 1.0);
+}";
+
+const FRAGMENT_SOURCE: &str = 
+"#version 440 core
+
+layout (location = 0) out vec4 frag_color;
+
+void main()
+{
+    frag_color = vec4(0.5, 0.5, 0.5, 0.5);
+}";
+
 //--Pipeline implementation-------------------------------------------------------------------------
 #[derive(Debug)]
 pub struct Pipeline<B: gfx_hal::Backend> {
-    render_pass: ManuallyDrop<B::RenderPass>,
+    set_layout: Vec<B::DescriptorSetLayout>,
+    layout: ManuallyDrop<B::PipelineLayout>, 
+    gfx_pipeline: ManuallyDrop<B::GraphicsPipeline>,
+    vertex_buffers: Vec<Attachement<B>>,
 }
 
 impl<B> Pipeline<B>
 where
     B: gfx_hal::Backend,
 {
+    pub fn drop(mut self, gpu: &mut Gpu<B>) {
+        use std::ptr::read;
+
+        use gfx_hal::device::Device;
+
+        debug!("Dropping Pipeline...");
+        for buffer in self.vertex_buffers.drain(..) {
+            buffer.drop(gpu);
+        }
+        unsafe {
+            gpu.device()
+                .destroy_graphics_pipeline(
+                    ManuallyDrop::into_inner(read(&mut self.gfx_pipeline)));
+            gpu.device()
+                .destroy_pipeline_layout(
+                    ManuallyDrop::into_inner(read(&mut self.layout)));
+            for layout in self.set_layout.drain(..) {
+                gpu.device().destroy_descriptor_set_layout(layout);
+        }}
+    }
+
+    pub fn new(gpu: &mut Gpu<B>, swap_system: &SwapSystem<B>) -> Result<Pipeline<B>, &'static str> {
+        use gfx_hal::{
+            device::Device,
+            pso::{EntryPoint, Specialization, VertexBufferDesc, VertexInputRate, AttributeDesc,
+                Element, InputAssemblerDesc, Primitive, PrimitiveAssemblerDesc, Rasterizer, 
+                PolygonMode, Face, FrontFace, State, DepthStencilDesc, BakedStates, Viewport,
+                DescriptorSetLayoutBinding, ShaderStageFlags
+            },
+            format::Format,
+        };
+
+        use std::borrow::Cow;
+
+        debug!("Compiling shaders...");
+        let mut compiler = shaderc::Compiler::new().ok_or("shaderc not found")?;
+        let vertex_compile_artifact = compiler
+            .compile_into_spirv(VERTEX_SOURCE, shaderc::ShaderKind::Vertex, "vertex.vert", 
+                                "main", 
+                                None)
+            .map_err(|err| {error!("{}", err); 
+                "Could not compile vertex shader"})?;
+        let fragment_compile_artifact = compiler
+            .compile_into_spirv(FRAGMENT_SOURCE, shaderc::ShaderKind::Fragment, "fragement.frag",
+                                "main",
+                                None)
+            .map_err(|err| {error!("{}", err); 
+                "Could not compile fragment shader"})?;
+
+        trace!("Creating ShaderModules...");
+        let vertex_shader_module = unsafe {
+            gpu.device()
+                .create_shader_module(vertex_compile_artifact.as_binary())
+                .map_err(|err| {error!("{}", err);
+                    "Could not create vertex shader module"})?
+        };
+        let fragment_shader_module = unsafe {
+            gpu.device()
+                .create_shader_module(fragment_compile_artifact.as_binary())
+                .map_err(|err| {error!("{}", err);
+                    "Could not create fragment shader module"})?
+            };
+
+        trace!("Creating shader set...");
+        let (vs_entry, fs_entry) = (
+            EntryPoint {
+                entry: "main",
+                module: &vertex_shader_module,
+                specialization: Specialization {
+                    constants: Cow::Borrowed{0: &[]},
+                    data: Cow::Borrowed{0: &[]},
+                },
+            },
+            EntryPoint {
+                entry: "main",
+                module: &fragment_shader_module,
+                specialization: Specialization {
+                    constants: Cow::Borrowed{0: &[]},
+                    data: Cow::Borrowed{0: &[]},
+                },
+            },
+        );
+        
+        trace!("Creating PrimitiveAssembler...");
+        let buffers: Vec<VertexBufferDesc> = 
+            vec![VertexBufferDesc {
+                binding: 0,
+                stride: (size_of::<f32>()*2) as u32,
+                rate: VertexInputRate::Vertex,
+            }];
+        let attributes: Vec<AttributeDesc> =
+            vec![AttributeDesc {
+                location: 0,
+                binding: 0,
+                element: Element {
+                    format: Format::Rgb32Sfloat,
+                    offset: 0,
+                },
+            }];
+        let input_assembler = InputAssemblerDesc {
+            primitive: Primitive::TriangleList,     //TODO switch to strips
+            with_adjacency: false,
+            restart_index: None,
+        };
+
+        let primitive_assembler = PrimitiveAssemblerDesc::Vertex {
+            buffers: &buffers,
+            attributes: &attributes,
+            input_assembler,
+            vertex: vs_entry,
+            tessellation: None,
+            geometry: None,
+        };
+        
+        trace!("Creating Rasterizer...");
+        let rasterizer = Rasterizer {
+            polygon_mode: PolygonMode::Fill,
+            cull_face: Face::NONE,              //TODO adjut that
+            front_face: FrontFace::CounterClockwise,
+            depth_clamping: false,
+            depth_bias: None,
+            conservative: false,
+            line_width: State::Static{0: 1.0}, //TODO may need to be changed
+        };
+
+        trace!("Configuring color blending...");
+        let blender = {
+            use gfx_hal::pso::{BlendState, BlendOp, Factor, BlendDesc, LogicOp, ColorBlendDesc, 
+                ColorMask};
+
+            let blend_state = BlendState {
+                color: BlendOp::Add {
+                    src: Factor::One,
+                    dst: Factor::Zero,
+                },
+                alpha: BlendOp::Add {
+                    src: Factor::One,
+                    dst: Factor::Zero,
+            }};
+            BlendDesc {
+                logic_op: Some(LogicOp::Copy),
+                targets: vec![
+                    ColorBlendDesc { 
+                        mask: ColorMask::ALL,
+                        blend: Some(blend_state),
+            }]}
+        };
+
+        trace!("Configuring depth options...");
+        let depth_stencil = DepthStencilDesc {
+            depth: None,
+            depth_bounds: false,
+            stencil: None,
+        };
+
+        trace!("Configuring baked-in pipeline states...");
+        let baked_states = BakedStates {
+            viewport: Some(Viewport {
+                rect: swap_system.render_area.clone(),
+                depth: (0.0..1.0),
+            }),
+            scissor: Some(swap_system.render_area.clone()),
+            blend_color: None,
+            depth_bounds: None,
+        };
+
+        trace!("Creating PipelineLayout...");
+        let set_layout = {
+            let bindings = Vec::<DescriptorSetLayoutBinding>::new();
+            let immutable_samplers = Vec::<B::Sampler>::new();
+            unsafe {
+                vec![gpu.device()
+                    .create_descriptor_set_layout(bindings, immutable_samplers)
+                    .map_err(|_| "Could not create DescriptorSetLayout")?
+        ]}};
+        let layout = {
+            let push_constants = Vec::<(ShaderStageFlags, std::ops::Range<u32>)>::new();
+            unsafe {
+                gpu.device()
+                    .create_pipeline_layout(&set_layout, push_constants)
+                    .map_err(|_| "Could not create PipelineLayout")?
+        }};
+
+        debug!("Creating GraphicsPipeline...");
+        let gfx_pipeline = {
+            use gfx_hal::{
+                pso::{GraphicsPipelineDesc, PipelineCreationFlags, BasePipeline},
+                pass::Subpass,
+            };
+
+            //manual deref for ManuallyDrop to not cause troubles
+            let render_pass_ref: &B::RenderPass = &swap_system.render_pass;
+
+            let pipeline_desc = GraphicsPipelineDesc {
+                primitive_assembler,
+                rasterizer,
+                fragment: Some(fs_entry),
+                blender,
+                depth_stencil,
+                multisampling: None,
+                baked_states,
+                layout: &layout,
+                subpass: Subpass {
+                    index: 0,
+                    main_pass: render_pass_ref,
+                },
+                flags: PipelineCreationFlags::empty(),
+                parent: BasePipeline::None,
+            };
+
+            unsafe {
+                gpu.device()
+                    .create_graphics_pipeline(&pipeline_desc, None)
+                    .map_err(|_| "Could not create GraphicsPipeline")?
+        }};
+
+        trace!("Destroying no-longer-needed shader modules...");
+        unsafe {
+            gpu.device()
+                .destroy_shader_module(vertex_shader_module);
+            gpu.device()
+                .destroy_shader_module(fragment_shader_module);
+        };
+
+        let vertex_buffers = vec![Attachement::new(gpu)?];
+
+        Ok( Pipeline {
+            set_layout,
+            layout: ManuallyDrop::new(layout),
+            gfx_pipeline: ManuallyDrop::new(gfx_pipeline),
+            vertex_buffers,
+        })
+    }
+
+    pub fn raw_pipeline(&self) -> &B::GraphicsPipeline {
+        &self.gfx_pipeline
+    }
+
+    pub fn raw_vertex_buffers(&self) -> Vec<(&B::Buffer, SubRange)> {
+
+        self.vertex_buffers
+            .iter()
+            //TODO move SubRange to Attachement ?
+            .map(|buffer| (buffer.get_buffer(), SubRange {offset: 0, size: None}))
+            .collect()
+    }
+
+    pub fn write_vertex_buffer(&mut self, gpu: &Gpu<B>, index: usize, data: Vec<f32>) 
+        -> Result<(), &'static str>
+    {
+        self.vertex_buffers[index].write_buffer(gpu, data)
+    }
 
 }
 

src/renderer/pipeline/attachement.rs

@@ -0,0 +1,135 @@
+#[allow(unused_imports)]
+use log::{debug, error, info, trace, warn};
+
+use std::mem::ManuallyDrop;
+
+use crate::renderer::gpu::Gpu;
+
+//--Attachement implementation----------------------------------------------------------------------
+#[derive(Debug)]
+pub struct Attachement<B: gfx_hal::Backend> {
+    buffer: ManuallyDrop<B::Buffer>,
+    memory: ManuallyDrop<B::Memory>,
+    size: u64,
+}
+
+impl<B> Attachement<B>
+where
+    B: gfx_hal::Backend,
+{
+    pub fn drop(mut self, gpu: &mut Gpu<B>) {
+        use std::ptr::read;
+
+        use gfx_hal::device::Device;
+
+        debug!("Dropping Attachement...");
+        unsafe {
+            gpu.device()
+                .free_memory(ManuallyDrop::into_inner(read(&mut self.memory)));
+            gpu.device()
+                .destroy_buffer(ManuallyDrop::into_inner(read(&mut self.buffer)));
+        }
+    }
+
+    pub fn new(gpu: &mut Gpu<B>) -> Result<Attachement<B>, &'static str> {
+        use std::mem::size_of;
+        
+        use gfx_hal::{
+            device::Device,
+            adapter::PhysicalDevice,
+            buffer::Usage,
+        };
+
+        debug!("Creating attachement...");
+        let mut buffer = unsafe {
+            gpu.device()
+                .create_buffer((size_of::<f32>()*2*3) as u64, Usage::VERTEX)
+                .map_err(|_| "Could not create buffer")?
+        };
+
+        trace!("Creating underlying attachement memory...");
+        let (memory, size) = {
+            use gfx_hal::{
+                memory::Properties, 
+                MemoryTypeId,
+            };
+
+            let requirements = unsafe {
+                gpu.device().get_buffer_requirements(&buffer)
+            };
+            let memory_type = gpu.adapter()
+                .physical_device
+                .memory_properties()
+                .memory_types
+                .iter()
+                .enumerate()
+                .find(|&(id, memory_type)| {
+                    requirements.type_mask & (1 << id) != 0 &&
+                        memory_type.properties.contains(Properties::CPU_VISIBLE)})
+                .map(|(id, _)| MemoryTypeId(id))
+                .ok_or("Could not find a suitable memory type to allocate attachement memory")?;
+
+            (
+                unsafe {
+                    gpu.device()
+                        .allocate_memory(memory_type, requirements.size)
+                        .map_err(|_| "Could not allocate buffer memory...")?
+                },
+                requirements.size,
+        )};
+
+        trace!("Binding memory to buffer...");
+        unsafe {
+            gpu.device()
+                .bind_buffer_memory(&memory, 0, &mut buffer)
+                .map_err(|__| "Could not bind memory to buffer")?;
+        }
+
+
+        Ok( Attachement {
+            buffer: ManuallyDrop::new(buffer),
+            memory: ManuallyDrop::new(memory),
+            size,
+        })
+    }
+
+    pub fn get_buffer(&self) -> &B::Buffer {
+        //manual deref for ManuallyDrop to not cause troubles
+        &self.buffer
+    }
+
+    pub fn write_buffer(&self, gpu: &Gpu<B>, data: Vec<f32>) -> Result<(), &'static str> 
+    {
+        use gfx_hal::{
+            device::Device,
+            memory::Segment,
+        };
+
+        trace!("writing data to buffer...");
+        unsafe {
+            let mapped_memory = gpu.device()
+                .map_memory(&self.memory, Segment::ALL)
+                .map_err(|_| "Could not map buffer memory")?;
+
+            //debug!("before : {}", std::ptr::read(mapped_memory as *mut f32));
+
+            std::ptr::copy_nonoverlapping(data.as_ptr() as *const u8, 
+                                          mapped_memory, self.size as usize);
+
+            //debug!("after : {}", std::ptr::read(mapped_memory as *mut f32));
+
+            //manual deref for ManuallyDrop to not cause troubles
+            let memory_ref: &B::Memory = &self.memory;
+
+            gpu.device()
+                .flush_mapped_memory_ranges(std::iter::once((memory_ref, Segment::ALL)))
+                .map_err(|_| "Could not flush mapped buffer memory")?;
+            
+            gpu.device().unmap_memory(&self.memory);
+        }
+
+        Ok(())
+    }
+
+}
+

src/renderer/swap_system.rs

@@ -25,7 +25,7 @@ pub struct SwapSystem<B: gfx_hal::Backend> {
     format: Format,
     extent: Extent2D,
     pub render_area: GfxRect, //TODO may not be needed (duplicate of extent)
-    pub render_pass: ManuallyDrop<B::RenderPass>,
+    pub render_pass: ManuallyDrop<B::RenderPass>, //TODO move to Pipeline ?
     frames: VecDeque<Frame<B>>,
     frame_nb: usize,
 }
@@ -51,7 +51,7 @@ where
         }
     }
 
-        pub fn new(gpu: &mut Gpu<B>, mut surface: B::Surface) 
+    pub fn new(gpu: &mut Gpu<B>, mut surface: B::Surface) 
         -> Result<SwapSystem<B>, &'static str> 
     {
 

src/subengine/subengine_pipeline.rs

@@ -25,7 +25,7 @@ where
     pub inputs: Vec<&'a RefCell<I>>,
     pub subengines: Vec<Vec<SubengineController>>,
     pub renderers: Vec<(Renderer<vk_back::Backend>, &'a RefCell<O>)>,
-    pub phantom: PhantomData<W>, //needed because of compiler limitations
+    phantom: PhantomData<W>, //needed because of compiler limitations
 }
 
 impl<'a, I, W, O> SubenginePipeline<'a, I, W, O> 

src/utils.rs

@@ -9,3 +9,16 @@ pub struct Rect<I: Num> {
     pub h: I,
 }
 
+#[derive(Debug, Copy, Clone)]
+pub struct Triangle {
+    pub points: [[f32; 2]; 3],
+}
+
+impl Triangle {
+
+    pub fn points_flat(&self) -> [f32; 6] {
+        let [[a, b], [c, d], [e, f]] = self.points;
+        [a, b, c, d, e, f]
+    }
+}
+