three_d/renderer/effect/
fog.rs

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
use crate::renderer::*;

///
/// An effect that simulates fog, ie. the area where it is applied gets hazy when objects are far away.
///
#[derive(Clone, Debug)]
pub struct FogEffect {
    /// The color of the fog.
    pub color: Srgba,
    /// The density of the fog.
    pub density: f32,
    /// Determines the variation on the density as a function of time.
    pub animation: f32,
    /// The time used for the animation.
    pub time: f32,
}

impl Default for FogEffect {
    fn default() -> Self {
        Self {
            color: Srgba::WHITE,
            density: 0.2,
            animation: 1.0,
            time: 0.0,
        }
    }
}

impl Effect for FogEffect {
    fn fragment_shader_source(
        &self,
        _lights: &[&dyn Light],
        color_texture: Option<ColorTexture>,
        depth_texture: Option<DepthTexture>,
    ) -> String {
        format!(
            "{}\n{}\n{}\n{}\n{}\n{}",
            include_str!("../../core/shared.frag"),
            color_texture
                .expect("Must supply a depth texture to apply a fog effect")
                .fragment_shader_source(),
            depth_texture
                .expect("Must supply a depth texture to apply a fog effect")
                .fragment_shader_source(),
            ToneMapping::fragment_shader_source(),
            ColorMapping::fragment_shader_source(),
            include_str!("shaders/fog_effect.frag")
        )
    }

    fn id(
        &self,
        color_texture: Option<ColorTexture>,
        depth_texture: Option<DepthTexture>,
    ) -> EffectMaterialId {
        EffectMaterialId::FogEffect(
            color_texture.expect("Must supply a color texture to apply a fog effect"),
            depth_texture.expect("Must supply a depth texture to apply a fog effect"),
        )
    }

    fn use_uniforms(
        &self,
        program: &Program,
        viewer: &dyn Viewer,
        _lights: &[&dyn Light],
        color_texture: Option<ColorTexture>,
        depth_texture: Option<DepthTexture>,
    ) {
        viewer.tone_mapping().use_uniforms(program);
        viewer.color_mapping().use_uniforms(program);
        color_texture
            .expect("Must supply a color texture to apply a fog effect")
            .use_uniforms(program);
        depth_texture
            .expect("Must supply a depth texture to apply a fog effect")
            .use_uniforms(program);
        program.use_uniform(
            "viewProjectionInverse",
            (viewer.projection() * viewer.view()).invert().unwrap(),
        );
        program.use_uniform("fogColor", Vec4::from(self.color));
        program.use_uniform("fogDensity", self.density);
        program.use_uniform("animation", self.animation);
        program.use_uniform("time", 0.001 * self.time);
        program.use_uniform("eyePosition", viewer.position());
    }

    fn render_states(&self) -> RenderStates {
        RenderStates {
            depth_test: DepthTest::Always,
            cull: Cull::Back,
            ..Default::default()
        }
    }
}