kit 0.0.2

An small game engine for 3D games.
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

use crate::graphics::*;
use crate::math::*;
use crate::*;
use std::mem::size_of;

pub fn draw_point(ctx: &mut Ctx, pos: V2, color: V4) {
    let i = ctx.gl.points.count;
    // TODO debug only?
    if i >= MAX_POINTS {
        panic!("can't draw that many points!")
    }
    ctx.gl.points.count += 1;
    ctx.gl.points.e[i] = DrawPoint::new(pos.x, pos.y, 0.0, color);
}

pub fn init(ctx: &mut Ctx) {
    let (vs_src, fs_src) = match sg_api() {
        SgApi::OpenGL33 => (
            include_str!("point.vert.glsl"),
            include_str!("point.frag.glsl"),
        ),
        SgApi::Metal => (
            include_str!("point.vs.metal"),
            include_str!("point.fs.metal"),
        ),
        _ => panic!(),
    };

    let shader_desc = SgShaderDesc {
        vs: SgShaderStageDesc {
            source: Some(vs_src),
            uniform_blocks: vec![std_uniform_block()],
            ..Default::default()
        },
        fs: SgShaderStageDesc {
            source: Some(fs_src),
            ..Default::default()
        },
        attrs: vec![],
    };
    let shader = sg_make_shader(&shader_desc);
    let layout = SgLayoutDesc {
        attrs: vec![
            SgVertexAttrDesc {
                // name: "in_position",
                format: SgVertexFormat::Float3,
                ..Default::default()
            },
            SgVertexAttrDesc {
                // name: "in_color",
                format: SgVertexFormat::Float4,
                ..Default::default()
            },
        ],
        ..Default::default()
    };
    let point_pipeline_desc = SgPipelineDesc {
        primitive_type: SgPrimitiveType::Points,
        shader,
        layout,
        ..Default::default()
    };
    let pipeline = sg_make_pipeline(&point_pipeline_desc);

    let vertex_buffer_desc = SgBufferDesc {
        buffer_type: SgBufferType::VertexBuffer,
        size: BYTES_POINTS,
        usage: SgUsage::Stream,
    };
    let vertex_buffer = sg_make_buffer::<()>(None, &vertex_buffer_desc);
    let vertex_buffers = vec![vertex_buffer];
    let bindings = SgBindings {
        vertex_buffers,
        ..Default::default()
    };
    ctx.gl.points.shape = GlShape { bindings, pipeline };
}

pub fn present(ctx: &mut Ctx) {
    sg_update_buffer(
        ctx.gl.points.shape.bindings.vertex_buffers[0],
        &ctx.gl.points.e,
        (ctx.gl.points.count * size_of::<DrawPoint>()) as i32,
    );
    sg_apply_pipeline(ctx.gl.points.shape.pipeline);
    sg_apply_bindings(&ctx.gl.points.shape.bindings);
    sg_apply_uniforms(
        SgShaderStage::Vertex,
        0,
        &ctx.gl.view_proj,
        size_of::<M4>() as i32,
    );
    sg_draw(0, ctx.gl.points.count as i32, 1);
}