tv.yaml

import:
    - ../block.yaml
    
styles:
    filter-tv:
        mix: [block]
        doc:
            author: 
                name: Patricio Gonzalez Vivo
                twitter: patriciogv
            version: 0.0.1
            tangram-version: 0.0.7
            licence: MIT
            description: |  
                Apply an old TV effect to the style.
            examples:
                9845C:
                    url: https://tangrams.github.io/tangram-sandbox/styles/9845C.yaml
                    img: https://tangrams.github.io/tangram-sandbox/styles/9845C.png
        ui:
            shaders:
                defines:
                    TV_FREQ: 
                        type: number
                        label: Frequency
                        range: 
                            min: 0.
                            max: 10.
                            step: 0.1
                    TV_SPEED: 
                        type: number
                        label: Speed
                        range: 
                            min: 0.
                            max: 10.
                            step: 0.1
                    TV_AMOUNT: 
                        type: number
                        label: amount
                        range: 
                            min: 0.
                            max: 1.
                            step: 0.01
                    TV_BLEND: 
                        type: dropdownArray
                        label: 'blend mode'
                        values: ['ADD', 'SUBTRACT', 'MULTIPLY']
        test:
            tv: { uniforms: { u_tex0: "https://tangrams.github.io/blocks/test.jpg" }, blocks: { color: "    color = texture2D(u_tex0,v_texcoord.xy);" } }

        shaders:
            defines:
                TV_AMOUNT: 1.
                TV_FREQ: 2.7
                TV_SPEED: 5.
                TV_BLEND: 'MULTIPLY'
            blocks: 
                filter: |
                    color = color TV_BLEND (abs(cos((gl_FragCoord.y*(TV_FREQ/u_device_pixel_ratio)+u_time*TV_SPEED)))*TV_AMOUNT);