hoplite 0.1.9

A creative coding framework for Rust that gets out of your way
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

// Standard 3D mesh shader with basic lighting and texture support
// Uses instanced rendering with a storage buffer for per-instance data

struct CameraUniforms {
    view_proj: mat4x4f,
    view: mat4x4f,
    proj: mat4x4f,
    camera_pos: vec3f,
    time: f32,
}

struct InstanceData {
    model: mat4x4f,
    normal_matrix: mat4x4f,
    color: vec4f,
}

@group(0) @binding(0) var<uniform> camera: CameraUniforms;
@group(1) @binding(0) var<storage, read> instances: array<InstanceData>;
@group(2) @binding(0) var t_diffuse: texture_2d<f32>;
@group(2) @binding(1) var s_diffuse: sampler;

struct VertexInput {
    @location(0) position: vec3f,
    @location(1) normal: vec3f,
    @location(2) uv: vec2f,
    @builtin(instance_index) instance_idx: u32,
}

struct VertexOutput {
    @builtin(position) clip_position: vec4f,
    @location(0) world_pos: vec3f,
    @location(1) world_normal: vec3f,
    @location(2) uv: vec2f,
    @location(3) @interpolate(flat) instance_idx: u32,
}

@vertex
fn vs(in: VertexInput) -> VertexOutput {
    let instance = instances[in.instance_idx];
    let world_pos = instance.model * vec4f(in.position, 1.0);
    let world_normal = normalize((instance.normal_matrix * vec4f(in.normal, 0.0)).xyz);

    var out: VertexOutput;
    out.clip_position = camera.view_proj * world_pos;
    out.world_pos = world_pos.xyz;
    out.world_normal = world_normal;
    out.uv = in.uv;
    out.instance_idx = in.instance_idx;
    return out;
}

@fragment
fn fs(in: VertexOutput) -> @location(0) vec4f {
    let instance = instances[in.instance_idx];
    let normal = normalize(in.world_normal);
    let view_dir = normalize(camera.camera_pos - in.world_pos);

    // Sample texture
    let tex_color = textureSample(t_diffuse, s_diffuse, in.uv);

    // Simple directional light from above-right
    let light_dir = normalize(vec3f(0.5, 1.0, 0.3));
    let light_color = vec3f(1.0, 0.98, 0.95);

    // Ambient
    let ambient = 0.15;

    // Diffuse (half-lambert for softer look)
    let ndotl = dot(normal, light_dir);
    let diffuse = ndotl * 0.5 + 0.5;

    // Specular (Blinn-Phong) - reduced for textured surfaces
    let half_vec = normalize(light_dir + view_dir);
    let spec = pow(max(dot(normal, half_vec), 0.0), 32.0) * 0.3;

    // Rim light for edge definition
    let rim = pow(1.0 - max(dot(normal, view_dir), 0.0), 3.0) * 0.15;

    // Combine texture color with instance color (tint)
    let base_color = tex_color.rgb * instance.color.rgb;
    let lighting = ambient + diffuse * light_color + spec + rim;
    let final_color = base_color * lighting;

    return vec4f(final_color, tex_color.a * instance.color.a);
}