vger 0.4.0

2D GPU renderer for dynamic UIs
Documentation 
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
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131

use crate::*;

pub const MAX_LAYERS: usize = 4;

type Mat4x4 = [f32; 16];

pub(crate) struct Scene {
    pub prims: [GPUVec<Prim>; MAX_LAYERS],
    pub cvs: GPUVec<LocalPoint>,
    pub xforms: GPUVec<Mat4x4>,
    pub paints: GPUVec<Paint>,
    pub scissors: GPUVec<Scissor>,
    pub bind_groups: [wgpu::BindGroup; MAX_LAYERS],
}

pub const MAX_PRIMS: usize = 65536;

// Initial prim capacity.
pub const INIT_PRIMS: usize = 1024;

impl Scene {
    pub fn new(device: &wgpu::Device) -> Self {
        let prims = [
            GPUVec::new(device, INIT_PRIMS, "Prim Buffer 0"),
            GPUVec::new(device, INIT_PRIMS, "Prim Buffer 1"),
            GPUVec::new(device, INIT_PRIMS, "Prim Buffer 2"),
            GPUVec::new(device, INIT_PRIMS, "Prim Buffer 3"),
        ];

        let cvs = GPUVec::new(device, INIT_PRIMS, "cv Buffer");
        let xforms = GPUVec::new(device, INIT_PRIMS, "Xform Buffer");
        let paints = GPUVec::new(device, INIT_PRIMS, "Paint Buffer");
        let scissors = GPUVec::new(device, INIT_PRIMS, "scissor Buffer");

        let bind_group_layout = Self::bind_group_layout(device);

        let bind_groups = [0, 1, 2, 3].map(|i| {
            Scene::bind_group(
                device,
                &bind_group_layout,
                &prims[i],
                &cvs,
                &xforms,
                &paints,
                &scissors,
            )
        });

        Self {
            prims,
            cvs,
            xforms,
            paints,
            scissors,
            bind_groups,
        }
    }

    pub fn bind_group_layout(device: &wgpu::Device) -> wgpu::BindGroupLayout {
        device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
            entries: &[
                GPUVec::<Prim>::bind_group_layout_entry(0),
                GPUVec::<LocalPoint>::bind_group_layout_entry(1),
                GPUVec::<Mat4x4>::bind_group_layout_entry(2),
                GPUVec::<Paint>::bind_group_layout_entry(3),
                GPUVec::<Scissor>::bind_group_layout_entry(4),
            ],
            label: Some("BindGroupLayout for Scene"),
        })
    }

    fn bind_group(
        device: &wgpu::Device,
        bind_group_layout: &wgpu::BindGroupLayout,
        prims: &GPUVec<Prim>,
        cvs: &GPUVec<LocalPoint>,
        xforms: &GPUVec<Mat4x4>,
        paints: &GPUVec<Paint>,
        scissors: &GPUVec<Scissor>,
    ) -> wgpu::BindGroup {
        device.create_bind_group(&wgpu::BindGroupDescriptor {
            layout: bind_group_layout,
            entries: &[
                prims.bind_group_entry(0),
                cvs.bind_group_entry(1),
                xforms.bind_group_entry(2),
                paints.bind_group_entry(3),
                scissors.bind_group_entry(4),
            ],
            label: Some("vger bind group"),
        })
    }

    pub fn update(&mut self, device: &wgpu::Device, queue: &wgpu::Queue) {
        let mut update_bind_groups = false;

        for i in 0..4 {
            update_bind_groups |= self.prims[i].update(device, queue);
        }
        update_bind_groups |= self.cvs.update(device, queue);
        update_bind_groups |= self.xforms.update(device, queue);
        update_bind_groups |= self.paints.update(device, queue);
        update_bind_groups |= self.scissors.update(device, queue);

        // If anything changed, regenerate all the bind groups.
        if update_bind_groups {
            let bind_group_layout = Scene::bind_group_layout(device);
            for layer in 0..MAX_LAYERS {
                self.bind_groups[layer] = Scene::bind_group(
                    device,
                    &bind_group_layout,
                    &self.prims[layer],
                    &self.cvs,
                    &self.xforms,
                    &self.paints,
                    &self.scissors,
                );
            }
        }
    }

    pub fn clear(&mut self) {
        for i in 0..4 {
            self.prims[i].clear();
        }
        self.cvs.clear();
        self.xforms.clear();
        self.paints.clear();
        self.scissors.clear();
    }
}