Added support for custom shader widget for iced_wgpu backend.

4 files changed, 414 insertions, 0 deletions

diff --git a/examples/custom_shader/src/primitive/buffer.rs b/examples/custom_shader/src/primitive/buffer.rs
new file mode 100644
index 00000000..377ce1bb
--- /dev/null
+++ b/examples/custom_shader/src/primitive/buffer.rs
@@ -0,0 +1,39 @@
+// A custom buffer container for dynamic resizing.
+pub struct Buffer {
+    pub raw: wgpu::Buffer,
+    label: &'static str,
+    size: u64,
+    usage: wgpu::BufferUsages,
+}
+
+impl Buffer {
+    pub fn new(
+        device: &wgpu::Device,
+        label: &'static str,
+        size: u64,
+        usage: wgpu::BufferUsages,
+    ) -> Self {
+        Self {
+            raw: device.create_buffer(&wgpu::BufferDescriptor {
+                label: Some(label),
+                size,
+                usage,
+                mapped_at_creation: false,
+            }),
+            label,
+            size,
+            usage,
+        }
+    }
+
+    pub fn resize(&mut self, device: &wgpu::Device, new_size: u64) {
+        if new_size > self.size {
+            self.raw = device.create_buffer(&wgpu::BufferDescriptor {
+                label: Some(self.label),
+                size: new_size,
+                usage: self.usage,
+                mapped_at_creation: false,
+            });
+        }
+    }
+}
diff --git a/examples/custom_shader/src/primitive/cube.rs b/examples/custom_shader/src/primitive/cube.rs
new file mode 100644
index 00000000..c23f2132
--- /dev/null
+++ b/examples/custom_shader/src/primitive/cube.rs
@@ -0,0 +1,324 @@
+use crate::primitive::Vertex;
+use glam::{vec2, vec3, Vec3};
+use rand::{thread_rng, Rng};
+
+/// A single instance of a cube.
+#[derive(Debug, Clone)]
+pub struct Cube {
+    pub rotation: glam::Quat,
+    pub position: Vec3,
+    pub size: f32,
+    rotation_dir: f32,
+    rotation_axis: glam::Vec3,
+}
+
+impl Default for Cube {
+    fn default() -> Self {
+        Self {
+            rotation: glam::Quat::IDENTITY,
+            position: glam::Vec3::ZERO,
+            size: 0.1,
+            rotation_dir: 1.0,
+            rotation_axis: glam::Vec3::Y,
+        }
+    }
+}
+
+impl Cube {
+    pub fn new(size: f32, origin: Vec3) -> Self {
+        let rnd = thread_rng().gen_range(0.0..=1.0f32);
+
+        Self {
+            rotation: glam::Quat::IDENTITY,
+            position: origin + Vec3::new(0.1, 0.1, 0.1),
+            size,
+            rotation_dir: if rnd <= 0.5 { -1.0 } else { 1.0 },
+            rotation_axis: if rnd <= 0.33 {
+                glam::Vec3::Y
+            } else if rnd <= 0.66 {
+                glam::Vec3::X
+            } else {
+                glam::Vec3::Z
+            },
+        }
+    }
+
+    pub fn update(&mut self, size: f32, time: f32) {
+        self.rotation = glam::Quat::from_axis_angle(
+            self.rotation_axis,
+            time / 2.0 * self.rotation_dir,
+        );
+        self.size = size;
+    }
+}
+
+#[derive(Clone, Copy, bytemuck::Pod, bytemuck::Zeroable, Debug)]
+#[repr(C)]
+pub struct Raw {
+    transformation: glam::Mat4,
+    normal: glam::Mat3,
+    _padding: [f32; 3],
+}
+
+impl Raw {
+    const ATTRIBS: [wgpu::VertexAttribute; 7] = wgpu::vertex_attr_array![
+        //cube transformation matrix
+        4 => Float32x4,
+        5 => Float32x4,
+        6 => Float32x4,
+        7 => Float32x4,
+        //normal rotation matrix
+        8 => Float32x3,
+        9 => Float32x3,
+        10 => Float32x3,
+    ];
+
+    pub fn desc<'a>() -> wgpu::VertexBufferLayout<'a> {
+        wgpu::VertexBufferLayout {
+            array_stride: std::mem::size_of::<Self>() as wgpu::BufferAddress,
+            step_mode: wgpu::VertexStepMode::Instance,
+            attributes: &Self::ATTRIBS,
+        }
+    }
+}
+
+impl Raw {
+    pub fn from_cube(cube: &Cube) -> Raw {
+        Raw {
+            transformation: glam::Mat4::from_scale_rotation_translation(
+                glam::vec3(cube.size, cube.size, cube.size),
+                cube.rotation,
+                cube.position,
+            ),
+            normal: glam::Mat3::from_quat(cube.rotation),
+            _padding: [0.0; 3],
+        }
+    }
+
+    pub fn vertices() -> [Vertex; 36] {
+        [
+            //face 1
+            Vertex {
+                pos: vec3(-0.5, -0.5, -0.5),
+                normal: vec3(0.0, 0.0, -1.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(0.0, 1.0),
+            },
+            Vertex {
+                pos: vec3(0.5, -0.5, -0.5),
+                normal: vec3(0.0, 0.0, -1.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(1.0, 1.0),
+            },
+            Vertex {
+                pos: vec3(0.5, 0.5, -0.5),
+                normal: vec3(0.0, 0.0, -1.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(1.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(0.5, 0.5, -0.5),
+                normal: vec3(0.0, 0.0, -1.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(1.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(-0.5, 0.5, -0.5),
+                normal: vec3(0.0, 0.0, -1.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(0.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(-0.5, -0.5, -0.5),
+                normal: vec3(0.0, 0.0, -1.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(0.0, 1.0),
+            },
+            //face 2
+            Vertex {
+                pos: vec3(-0.5, -0.5, 0.5),
+                normal: vec3(0.0, 0.0, 1.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(0.0, 1.0),
+            },
+            Vertex {
+                pos: vec3(0.5, -0.5, 0.5),
+                normal: vec3(0.0, 0.0, 1.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(1.0, 1.0),
+            },
+            Vertex {
+                pos: vec3(0.5, 0.5, 0.5),
+                normal: vec3(0.0, 0.0, 1.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(1.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(0.5, 0.5, 0.5),
+                normal: vec3(0.0, 0.0, 1.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(1.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(-0.5, 0.5, 0.5),
+                normal: vec3(0.0, 0.0, 1.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(0.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(-0.5, -0.5, 0.5),
+                normal: vec3(0.0, 0.0, 1.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(0.0, 1.0),
+            },
+            //face 3
+            Vertex {
+                pos: vec3(-0.5, 0.5, 0.5),
+                normal: vec3(-1.0, 0.0, 0.0),
+                tangent: vec3(0.0, 0.0, -1.0),
+                uv: vec2(0.0, 1.0),
+            },
+            Vertex {
+                pos: vec3(-0.5, 0.5, -0.5),
+                normal: vec3(-1.0, 0.0, 0.0),
+                tangent: vec3(0.0, 0.0, -1.0),
+                uv: vec2(1.0, 1.0),
+            },
+            Vertex {
+                pos: vec3(-0.5, -0.5, -0.5),
+                normal: vec3(-1.0, 0.0, 0.0),
+                tangent: vec3(0.0, 0.0, -1.0),
+                uv: vec2(1.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(-0.5, -0.5, -0.5),
+                normal: vec3(-1.0, 0.0, 0.0),
+                tangent: vec3(0.0, 0.0, -1.0),
+                uv: vec2(1.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(-0.5, -0.5, 0.5),
+                normal: vec3(-1.0, 0.0, 0.0),
+                tangent: vec3(0.0, 0.0, -1.0),
+                uv: vec2(0.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(-0.5, 0.5, 0.5),
+                normal: vec3(-1.0, 0.0, 0.0),
+                tangent: vec3(0.0, 0.0, -1.0),
+                uv: vec2(0.0, 1.0),
+            },
+            //face 4
+            Vertex {
+                pos: vec3(0.5, 0.5, 0.5),
+                normal: vec3(1.0, 0.0, 0.0),
+                tangent: vec3(0.0, 0.0, -1.0),
+                uv: vec2(0.0, 1.0),
+            },
+            Vertex {
+                pos: vec3(0.5, 0.5, -0.5),
+                normal: vec3(1.0, 0.0, 0.0),
+                tangent: vec3(0.0, 0.0, -1.0),
+                uv: vec2(1.0, 1.0),
+            },
+            Vertex {
+                pos: vec3(0.5, -0.5, -0.5),
+                normal: vec3(1.0, 0.0, 0.0),
+                tangent: vec3(0.0, 0.0, -1.0),
+                uv: vec2(1.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(0.5, -0.5, -0.5),
+                normal: vec3(1.0, 0.0, 0.0),
+                tangent: vec3(0.0, 0.0, -1.0),
+                uv: vec2(1.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(0.5, -0.5, 0.5),
+                normal: vec3(1.0, 0.0, 0.0),
+                tangent: vec3(0.0, 0.0, -1.0),
+                uv: vec2(0.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(0.5, 0.5, 0.5),
+                normal: vec3(1.0, 0.0, 0.0),
+                tangent: vec3(0.0, 0.0, -1.0),
+                uv: vec2(0.0, 1.0),
+            },
+            //face 5
+            Vertex {
+                pos: vec3(-0.5, -0.5, -0.5),
+                normal: vec3(0.0, -1.0, 0.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(0.0, 1.0),
+            },
+            Vertex {
+                pos: vec3(0.5, -0.5, -0.5),
+                normal: vec3(0.0, -1.0, 0.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(1.0, 1.0),
+            },
+            Vertex {
+                pos: vec3(0.5, -0.5, 0.5),
+                normal: vec3(0.0, -1.0, 0.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(1.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(0.5, -0.5, 0.5),
+                normal: vec3(0.0, -1.0, 0.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(1.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(-0.5, -0.5, 0.5),
+                normal: vec3(0.0, -1.0, 0.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(0.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(-0.5, -0.5, -0.5),
+                normal: vec3(0.0, -1.0, 0.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(0.0, 1.0),
+            },
+            //face 6
+            Vertex {
+                pos: vec3(-0.5, 0.5, -0.5),
+                normal: vec3(0.0, 1.0, 0.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(0.0, 1.0),
+            },
+            Vertex {
+                pos: vec3(0.5, 0.5, -0.5),
+                normal: vec3(0.0, 1.0, 0.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(1.0, 1.0),
+            },
+            Vertex {
+                pos: vec3(0.5, 0.5, 0.5),
+                normal: vec3(0.0, 1.0, 0.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(1.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(0.5, 0.5, 0.5),
+                normal: vec3(0.0, 1.0, 0.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(1.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(-0.5, 0.5, 0.5),
+                normal: vec3(0.0, 1.0, 0.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(0.0, 0.0),
+            },
+            Vertex {
+                pos: vec3(-0.5, 0.5, -0.5),
+                normal: vec3(0.0, 1.0, 0.0),
+                tangent: vec3(1.0, 0.0, 0.0),
+                uv: vec2(0.0, 1.0),
+            },
+        ]
+    }
+}
diff --git a/examples/custom_shader/src/primitive/uniforms.rs b/examples/custom_shader/src/primitive/uniforms.rs
new file mode 100644
index 00000000..4fcb413b
--- /dev/null
+++ b/examples/custom_shader/src/primitive/uniforms.rs
@@ -0,0 +1,22 @@
+use crate::camera::Camera;
+use iced::{Color, Rectangle};
+
+#[derive(Copy, Clone, Debug, bytemuck::Pod, bytemuck::Zeroable)]
+#[repr(C)]
+pub struct Uniforms {
+    camera_proj: glam::Mat4,
+    camera_pos: glam::Vec4,
+    light_color: glam::Vec4,
+}
+
+impl Uniforms {
+    pub fn new(camera: &Camera, bounds: Rectangle, light_color: Color) -> Self {
+        let camera_proj = camera.build_view_proj_matrix(bounds);
+
+        Self {
+            camera_proj,
+            camera_pos: camera.position(),
+            light_color: glam::Vec4::from(light_color.into_linear()),
+        }
+    }
+}
diff --git a/examples/custom_shader/src/primitive/vertex.rs b/examples/custom_shader/src/primitive/vertex.rs
new file mode 100644
index 00000000..6d17aa0f
--- /dev/null
+++ b/examples/custom_shader/src/primitive/vertex.rs
@@ -0,0 +1,29 @@
+#[derive(Debug, Copy, Clone, bytemuck::Pod, bytemuck::Zeroable)]
+#[repr(C)]
+pub struct Vertex {
+    pub pos: glam::Vec3,
+    pub normal: glam::Vec3,
+    pub tangent: glam::Vec3,
+    pub uv: glam::Vec2,
+}
+
+impl Vertex {
+    const ATTRIBS: [wgpu::VertexAttribute; 4] = wgpu::vertex_attr_array![
+        //position
+        0 => Float32x3,
+        //normal
+        1 => Float32x3,
+        //tangent
+        2 => Float32x3,
+        //uv
+        3 => Float32x2,
+    ];
+
+    pub fn desc<'a>() -> wgpu::VertexBufferLayout<'a> {
+        wgpu::VertexBufferLayout {
+            array_stride: std::mem::size_of::<Self>() as wgpu::BufferAddress,
+            step_mode: wgpu::VertexStepMode::Vertex,
+            attributes: &Self::ATTRIBS,
+        }
+    }
+}