simple_test.bp

vertex_shader :: vert {
	# test comment
    model: [f32; 4, 4];
    rotation: [f32; 4, 4];
    view: [f32; 4, 4];
    proj: [f32; 4, 4];

    dir_light: struct {
        dir: [f32; 3],
		color: [f32; 3],
    };
    ambient_light: [f32; 3];

    main :: (
		vertex: struct {
			pos: [f32; 3],
			uv: [f32; 2],
			norm: [f32; 3],
		},
    ) -> struct {
		pos: [f32; 3],
		uv: [f32; 2],
		light: [f32; 3],
	} = {
		pos := proj * view * model * [vertex.pos, 1];
		pos := pos.xyz;

		norm := rotation * [vertex.norm, 0];
		norm := norm.xyz;
		light := if (-dir_light * norm) > 0 { -dir_light * norm } else { 0 }; # because of lazy evaluation, `-dir_light * norm` is only evaluated once
		light := dir_light.color * light + ambient_light;

		struct {
			pos: pos,
			uv: vertex.uv,
			light: light,
		}
    }
}

fragment_shader :: frag {
    tex: Texture;

    main :: (
		frag: struct {
			pos: [f32; 3],
			uv: [f32; 2],
			light: [f32; 3],
		},
    ) -> [f32; 4] = tex.sample(frag.uv).multiply_elements(frag.light);
}

object := struct {
    vert_buffer: [ # of type [struct {pos: [f32; 3], uv: [f32; 2], norm: [f32; 3],}; 8]
		struct { pos: [0.0, 0.0, 0.0], uv: [0.0, 0.0], norm: [0.0, 0.0, 0.0] },
		struct { pos: [1.0, 0.0, 0.0], uv: [1.0, 0.0], norm: [1.0, 0.0, 0.0] },
		struct { pos: [1.0, 1.0, 0.0], uv: [1.0, 1.0], norm: [1.0, 1.0, 0.0] },
		struct { pos: [0.0, 1.0, 0.0], uv: [0.0, 1.0], norm: [0.0, 1.0, 0.0] },
		struct { pos: [0.0, 0.0, 1.0], uv: [0.0, 0.0], norm: [0.0, 0.0, 1.0] },
		struct { pos: [1.0, 0.0, 1.0], uv: [1.0, 0.0], norm: [1.0, 0.0, 1.0] },
		struct { pos: [1.0, 1.0, 1.0], uv: [1.0, 1.0], norm: [1.0, 1.0, 1.0] },
		struct { pos: [0.0, 1.0, 1.0], uv: [0.0, 1.0], norm: [0.0, 1.0, 1.0] },
    ],
    index_buffer: [ # of type [u32; 36]
		0, 1, 2, 2, 3, 0,
		4, 5, 6, 6, 7, 4,
		0, 4, 7, 7, 3, 0,
		1, 5, 6, 6, 2, 1,
		0, 1, 5, 5, 4, 0,
		3, 2, 6, 6, 7, 3,
    ],
}

main :: () = {
    device := get_default_render_device();
    display := create_window(1280, 720);

    device.set_display(display);

    vertex_shader := vertex_shader.compile();
    fragment_shader := fragment_shader.compile();

    device.bind(vertex_shader);
    device.bind(fragment_shader);

    device.pushbuffer(VERTICES: object.vert_buffer);
    device.pushbuffer(INDICES: object.index_buffer);

    transform := struct {
        pos: [0.0, 0.0, 0.0],
        rot: [0.0, 0.0, 0.0],
        scale: [1.0, 1.0, 1.0],
    };
    camera := struct {
        pos: [0.0, 0.0, -5.0],
        rot: [0.0, 0.0, 0.0],
    };

    tex := Texture::blank(512, 512);
    fragment_shader.setuniforms(tex: tex);

    vertex_shader.setuniforms(
		dir_light: struct {
			dir: [0.0, 0.3, 0.7].normalized(),
			color: [0.7, 0.7, 0.7],
		},
        ambient_light: [0.3, 0.3, 0.3],
    );

    loop {
		t := Instant::now().seconds();
		transform.pos = [sin(t), 0.0, 0.0];
		transform.rot = [t * 3, t * 5, t * 7];

		camera.rot = [0.0, cos(t),0.0];

		clear([0.0, 0.0, 0.0, 1.0]);

		rotation := rotation(transform.rot); # defaults to yxz
		vertex_shader.setuniforms(
			model: model(transform.pos, rotation),
			rotation: rotation,
			view: view(camera.pos, camera.rot),
			proj: proj(display.aspect, 90.0, 0.1, 1000.0),
		);

		device.draw();
		device.swap_buffers();
    }
}