chevron.yaml

styles:
    lines-chevron:
        doc:
            author: 
                name: Patricio Gonzalez Vivo
                twitter: patriciogv
            version: 0.0.1
            tangram-version: 0.0.7
            licence: MIT
            description: |
                Apply a chevron pattern to a line

        ui:
            shaders:
                defines:
                    CHEVRON_SCALE:
                        type: number
                        label: Scale
                        range: 
                            min: 0.
                            max: 10.
                            step: 0.1
                    CHEVRON_SIZE:
                        type: number
                        label: Size
                        range: 
                            min: 0.
                            max: 10.
                            step: 0.1
                    CHEVRON_COLOR: 
                        type: color
                        label: Color
                    CHEVRON_ALPHA:
                        type: number
                        label: Alpha
                        range: 
                            min: 0.
                            max: 1.
                            step: 0.01
                    CHEVRON_BACKGROUND_COLOR: 
                        type: color
                        label: 'Background color'
                    CHEVRON_BACKGROUND_ALPHA:
                        type: number
                        label: Background alpha
                        range: 
                            min: 0.
                            max: 1.
                            step: 0.01
                    

        base: lines
        texcoords: true
        shaders:
            defines:
                CHEVRON_COLOR: color.rgb*.5
                CHEVRON_ALPHA: 1.
                CHEVRON_BACKGROUND_COLOR: color.rgb
                CHEVRON_BACKGROUND_ALPHA: color.a
                CHEVRON_SIZE: 1.
                CHEVRON_SCALE: 1.
            blocks:
                color: |
                    color = mix(vec4(CHEVRON_BACKGROUND_COLOR, CHEVRON_BACKGROUND_ALPHA),
                                vec4(CHEVRON_COLOR, CHEVRON_ALPHA),
                                step(.5,fract((v_texcoord.y+abs(v_texcoord.x-.5)) * CHEVRON_SCALE)*CHEVRON_SIZE));