1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84

use {
    crate::shader,
    wgpu::{BindGroup, BindGroupLayout, Device, TextureView},
};

/// Describes a frame render filter mode.
#[derive(Clone, Copy)]
pub enum FrameFilter {
    Nearest,
    Linear,
}

pub(crate) struct RenderFrame {
    view: TextureView,
    bind_group: BindGroup,
}

impl RenderFrame {
    pub fn new(
        (width, height): (u32, u32),
        filter: FrameFilter,
        device: &Device,
        layout: &BindGroupLayout,
    ) -> Self {
        use wgpu::*;

        let texture = device.create_texture(&TextureDescriptor {
            size: Extent3d {
                width,
                height,
                depth_or_array_layers: 1,
            },
            mip_level_count: 1,
            sample_count: 1,
            dimension: TextureDimension::D2,
            format: TextureFormat::Bgra8UnormSrgb,
            usage: TextureUsages::RENDER_ATTACHMENT
                | TextureUsages::COPY_DST
                | TextureUsages::TEXTURE_BINDING,
            label: Some("texture"),
            view_formats: &[],
        });

        let view = texture.create_view(&TextureViewDescriptor::default());

        let filter_mode = match filter {
            FrameFilter::Nearest => FilterMode::Nearest,
            FrameFilter::Linear => FilterMode::Linear,
        };

        let sampler = device.create_sampler(&SamplerDescriptor {
            address_mode_u: AddressMode::ClampToEdge,
            address_mode_v: AddressMode::ClampToEdge,
            mag_filter: filter_mode,
            min_filter: filter_mode,
            ..Default::default()
        });

        let bind_group = device.create_bind_group(&BindGroupDescriptor {
            layout,
            entries: &[
                BindGroupEntry {
                    binding: shader::POST_TDIFF_BINDING,
                    resource: BindingResource::TextureView(&view),
                },
                BindGroupEntry {
                    binding: shader::POST_SDIFF_BINDING,
                    resource: BindingResource::Sampler(&sampler),
                },
            ],
            label: Some("texture bind group"),
        });

        Self { view, bind_group }
    }

    pub fn view(&self) -> &TextureView {
        &self.view
    }

    pub fn bind_group(&self) -> &BindGroup {
        &self.bind_group
    }
}