rt: respect viewport extents when rendering

librashader-common/src/lib.rs

@@ -40,6 +40,7 @@ pub use viewport::Viewport;
 
 use num_traits::{AsPrimitive, Num};
 use std::convert::Infallible;
+use std::ops::{Add, Sub};
 use std::str::FromStr;
 
 #[repr(u32)]
@@ -200,6 +201,51 @@ impl<T> Size<T> {
     }
 }
 
+impl<T: Sub<Output=T>> Sub for Size<T> {
+    type Output = Size<T>;
+
+    fn sub(self, rhs: Self) -> Self::Output {
+        Self {
+            width: self.width - rhs.width,
+            height: self.height - rhs.height
+        }
+    }
+}
+
+impl<T: Sub<T, Output=T> + Copy> Sub<T> for Size<T> {
+    type Output = Size<T>;
+
+    fn sub(self, rhs: T) -> Self::Output {
+        Self {
+            width: self.width - rhs,
+            height: self.height - rhs
+        }
+    }
+}
+
+
+impl<T: Add<Output=T>> Add for Size<T> {
+    type Output = Size<T>;
+
+    fn add(self, rhs: Self) -> Self::Output {
+        Self {
+            width: self.width + rhs.width,
+            height: self.height + rhs.height
+        }
+    }
+}
+
+impl<T: Add<T, Output=T> + Copy> Add<T> for Size<T> {
+    type Output = Size<T>;
+
+    fn add(self, rhs: T) -> Self::Output {
+        Self {
+            width: self.width + rhs,
+            height: self.height + rhs
+        }
+    }
+}
+
 impl<T> From<Size<T>> for [f32; 4]
 where
     T: Copy + AsPrimitive<f32>,

librashader-common/src/viewport.rs

@@ -1,8 +1,16 @@
 use crate::Size;
 
 /// The rendering output of a filter chain.
+///
+/// Viewport coordinates are relative to the coordinate system of the
+/// target runtime. For correct results, `x` and `y`  should almost always be
+/// 0, and `size` should be the same as the size of the output texture.
+///
+/// Size uniforms will always be passed the full size of the output texture,
+/// regardless of the user-specified viewport size.
 pub struct Viewport<'a, T> {
-    /// The x offset to start rendering from.
+    /// The x offset to start rendering from. For correct results, this should almost
+    /// always be 0 to indicate the origin.
     pub x: f32,
     /// The y offset to begin rendering from.
     pub y: f32,

librashader-runtime-d3d11/src/filter_pass.rs

@@ -1,3 +1,4 @@
+use windows::Win32::Foundation::RECT;
 use crate::filter_chain::FilterCommon;
 use crate::options::FrameOptionsD3D11;
 use crate::texture::InputTexture;
@@ -253,18 +254,24 @@ impl FilterPass {
             ctx.RSSetViewports(Some(&[D3D11_VIEWPORT {
                 TopLeftX: output.x,
                 TopLeftY: output.y,
-                Width: output_size.width as f32,
+                Width: output.size.width as f32,
-                Height: output_size.height as f32,
+                Height: output.size.height as f32,
                 MinDepth: 0.0,
                 MaxDepth: 1.0,
-            }]))
+            }]));
+            ctx.RSSetScissorRects(Some(&[RECT {
+                left: output.x as i32,
+                top: output.y as i32,
+                right: output.size.width as i32,
+                bottom: output.size.height as i32,
+            }]));
         }
 
         parent.draw_quad.draw_quad(ctx, vbo_type);
 
         unsafe {
             // unbind resources.
-            ctx.PSSetShaderResources(0, Some(std::mem::transmute(NULL_TEXTURES.as_ref())));
+            ctx.PSSetShaderResources(0, Some(NULL_TEXTURES));
             ctx.OMSetRenderTargets(None, None);
         }
         Ok(())

librashader-runtime-d3d11/tests/hello_triangle/mod.rs

@@ -570,17 +570,20 @@ pub mod d3d11_hello_triangle {
 
                 // eprintln!("w: {} h: {}", backbuffer_desc.Width, backbuffer_desc.Height);
                 let output = resources.backbuffer_rtv.as_ref().unwrap().clone();
-                let size = output.size().unwrap();
+                let size: Size<u32> = output.size().unwrap();
                 self.filter
                     .frame(
                         None,
                         &srv,
                         &Viewport {
-                            x: 0f32,
+                            x: 100f32,
-                            y: 0f32,
+                            y: 100f32,
                             output,
                             mvp: None,
-                            size,
+                            size: Size {
+                                width: size.width - 200,
+                                height: size.height - 200,
+                            },
                         },
                         resources.frame_count,
                         None,

librashader-runtime-d3d12/src/filter_pass.rs

@@ -206,17 +206,17 @@ impl FilterPass {
             cmd.RSSetViewports(&[D3D12_VIEWPORT {
                 TopLeftX: output.x,
                 TopLeftY: output.y,
-                Width: output.output.size.width as f32,
+                Width: output.size.width as f32,
-                Height: output.output.size.height as f32,
+                Height: output.size.height as f32,
                 MinDepth: 0.0,
                 MaxDepth: 1.0,
             }]);
 
             cmd.RSSetScissorRects(&[RECT {
-                left: 0,
+                left: output.x as i32,
-                top: 0,
+                top: output.y as i32,
-                right: output.output.size.width as i32,
+                right: output.size.width as i32,
-                bottom: output.output.size.height as i32,
+                bottom: output.size.height as i32,
             }]);
 
             parent.draw_quad.draw_quad(&cmd, vbo_type)

librashader-runtime-d3d9/src/filter_pass.rs

@@ -193,8 +193,8 @@ impl FilterPass {
             device.SetViewport(&D3DVIEWPORT9 {
                 X: output.x as u32,
                 Y: output.y as u32,
-                Width: output_size.width,
+                Width: output.size.width,
-                Height: output_size.height,
+                Height: output.size.height,
                 MinZ: 0.0,
                 MaxZ: 1.0,
             })?;

librashader-runtime-gl/src/filter_pass.rs

@@ -133,12 +133,11 @@ impl<T: GLInterface> FilterPass<T> {
 
         unsafe {
             framebuffer.clear::<T::FramebufferInterface, false>();
-            let framebuffer_size = framebuffer.size;
             parent.context.viewport(
                 output.x,
                 output.y,
-                framebuffer_size.width as i32,
+                output.size.width as i32,
-                framebuffer_size.height as i32,
+                output.size.height as i32,
             );
 
             if framebuffer.format == glow::SRGB8_ALPHA8 {

librashader-runtime-mtl/src/graphics_pipeline.rs

@@ -207,15 +207,15 @@ impl MetalGraphicsPipeline {
             rpass.setScissorRect(MTLScissorRect {
                 x: output.x as usize,
                 y: output.y as usize,
-                width: output.output.width(),
+                width: output.size.width as usize,
-                height: output.output.height(),
+                height: output.size.height as usize
             });
 
             rpass.setViewport(MTLViewport {
                 originX: output.x as f64,
                 originY: output.y as f64,
-                width: output.output.width() as f64,
+                width: output.size.width as f64,
-                height: output.output.height() as f64,
+                height: output.size.height as f64,
                 znear: 0.0,
                 zfar: 1.0,
             });

librashader-runtime-vk/src/filter_pass.rs

@@ -183,13 +183,13 @@ impl FilterPass {
                         x: output.x as i32,
                         y: output.y as i32,
                     },
-                    extent: output.output.size.into(),
+                    extent: output.size.into(),
                 }],
             );
 
             parent
                 .device
-                .cmd_set_viewport(cmd, 0, &[output.output.size.into()]);
+                .cmd_set_viewport(cmd, 0, &[output.size.into()]);
             parent.draw_quad.draw_quad(&parent.device, cmd, vbo_type);
             self.graphics_pipeline.end_rendering(cmd);
         }

librashader-runtime-vk/tests/hello_triangle/mod.rs

@@ -23,7 +23,7 @@ use swapchain::VulkanSwapchain;
 use syncobjects::SyncObjects;
 use vulkan_base::VulkanBase;
 
-use librashader_common::Viewport;
+use librashader_common::{Size, Viewport};
 
 use librashader_runtime_vk::options::FrameOptionsVulkan;
 use winit::event::{Event, WindowEvent};

librashader-runtime-wgpu/src/graphics_pipeline.rs

@@ -310,15 +310,15 @@ impl WgpuGraphicsPipeline {
         render_pass.set_scissor_rect(
             output.x as u32,
             output.y as u32,
-            output.output.size.width,
+            output.size.width,
-            output.output.size.height,
+            output.size.height,
         );
 
         render_pass.set_viewport(
             output.x,
             output.y,
-            output.output.size.width as f32,
+            output.size.width as f32,
-            output.output.size.height as f32,
+            output.size.height as f32,
             0.0,
             1.0,
         );

librashader-runtime-wgpu/tests/hello_triangle.rs

@@ -4,7 +4,7 @@ use winit::{
     window::{Window, WindowBuilder},
 };
 
-use librashader_common::Viewport;
+use librashader_common::{Size, Viewport};
 use librashader_presets::ShaderPreset;
 use librashader_runtime_wgpu::FilterChainWgpu;
 use wgpu::util::DeviceExt;
@@ -290,15 +290,15 @@ impl<'a> State<'a> {
             .frame(
                 Arc::clone(&render_output),
                 &Viewport {
-                    x: 0.0,
+                    x: 100.0,
-                    y: 0.0,
+                    y: 100.0,
                     mvp: None,
                     output: librashader_runtime_wgpu::WgpuOutputView::new_from_raw(
                         &filter_view,
                         filter_output.size().into(),
                         filter_output.format(),
                     ),
-                    size: filter_output.size().into(),
+                    size: (Size::from(filter_output.size())) - 200,
                 },
                 &mut encoder,
                 self.frame_count,