StandardMaterial.ts

interface StandardAttributes {
    texture: ImageData;
}

interface StandardInputs {
    i_Points: Float32Array;
    i_Sample: Float32Array;
}

interface StandardUniforms {
    u_Texture: ImageBitmapSource;
}

class StandardMaterial extends Bifrost.GFX.Material<StandardAttributes, StandardInputs, StandardUniforms> {

    public shaders(): Bifrost.GFX.Material.Shaders {
        return {
            vertex: `
                in vec2 i_Points;
                in vec2 i_Sample;

                uniform vec2 engine_Resolution;

                out vec2 o_Sample;

                void main () {
                    vec2 one = i_Points / engine_Resolution;
                    vec2 two = one * 2.0;
                    vec2 clip = two - 1.0;
                    vec2 flip = vec2(1.0, -1.0);

                    gl_Position = vec4(clip * flip, 0.0, 1.0);
                    o_Sample = i_Sample;
                }
            `,
            fragment: `
                precision mediump float;

                in vec2 o_Sample;

                uniform sampler2D u_Texture;

                out vec4 o_Color;

                void main () {
                    o_Color = texture(u_Texture, o_Sample);
                }
            `
        };
    }

    public paint(): Bifrost.GFX.Material.Outputs<Inputs, Uniforms> {
        return {
            inputs: {
                i_Points: new Float32Array([
                    0, 0,
                    this.attributes.texture.width, 0,
                    0, this.attributes.texture.height,
                    0, this.attributes.texture.height,
                    this.attributes.texture.width, 0,
                    this.attributes.texture.width, this.attributes.texture.height
                ]),
                i_Sample: new Float32Array([
                    0, 0,
                    1, 0,
                    0, 1,
                    0, 1,
                    1, 0,
                    1, 1
                ])
            },
            uniforms: {
                u_Texture: this.attributes.texture
            }
        };
    }
}