#

API Docs for: 1.6.0
Show: Inherited Protected Private Deprecated

# File: src/pixi/filters/DisplacementFilter.js

    /**
     * @author Mat Groves http://matgroves.com/ @Doormat23
     */

    /**
     *
     * The DisplacementFilter class uses the pixel values from the specified texture (called the displacement map) to perform a displacement of an object.
     * You can use this filter to apply all manor of crazy warping effects
     * Currently the r property of the texture is used offset the x and the g propery of the texture is used to offset the y.
     * @class DisplacementFilter
     * @contructor
     * @param texture {Texture} The texture used for the displacemtent map * must be power of 2 texture at the moment
     */
    PIXI.DisplacementFilter = function(texture)
    {
        PIXI.AbstractFilter.call( this );

        this.passes = [this];
        texture.baseTexture._powerOf2 = true;

        // set the uniforms
        this.uniforms = {
            displacementMap: {type: 'sampler2D', value:texture},
            scale:           {type: '2f', value:{x:30, y:30}},
            offset:          {type: '2f', value:{x:0, y:0}},
            mapDimensions:   {type: '2f', value:{x:1, y:5112}},
            dimensions:   {type: '4fv', value:[0,0,0,0]}
        };

        if(texture.baseTexture.hasLoaded)
        {
            this.uniforms.mapDimensions.value.x = texture.width;
            this.uniforms.mapDimensions.value.y = texture.height;
        }
        else
        {
            this.boundLoadedFunction = this.onTextureLoaded.bind(this);

            texture.baseTexture.on('loaded', this.boundLoadedFunction);
        }

        this.fragmentSrc = [
            'precision mediump float;',
            'varying vec2 vTextureCoord;',
            'varying vec4 vColor;',
            'uniform sampler2D displacementMap;',
            'uniform sampler2D uSampler;',
            'uniform vec2 scale;',
            'uniform vec2 offset;',
            'uniform vec4 dimensions;',
            'uniform vec2 mapDimensions;',// = vec2(256.0, 256.0);',
            // 'const vec2 textureDimensions = vec2(750.0, 750.0);',

            'void main(void) {',
            '   vec2 mapCords = vTextureCoord.xy;',
            //'   mapCords -= ;',
            '   mapCords += (dimensions.zw + offset)/ dimensions.xy ;',
            '   mapCords.y *= -1.0;',
            '   mapCords.y += 1.0;',
            '   vec2 matSample = texture2D(displacementMap, mapCords).xy;',
            '   matSample -= 0.5;',
            '   matSample *= scale;',
            '   matSample /= mapDimensions;',
            '   gl_FragColor = texture2D(uSampler, vec2(vTextureCoord.x + matSample.x, vTextureCoord.y + matSample.y));',
            '   gl_FragColor.rgb = mix( gl_FragColor.rgb, gl_FragColor.rgb, 1.0);',
            '   vec2 cord = vTextureCoord;',

            //'   gl_FragColor =  texture2D(displacementMap, cord);',
         //   '   gl_FragColor = gl_FragColor;',
            '}'
        ];
    };

    PIXI.DisplacementFilter.prototype = Object.create( PIXI.AbstractFilter.prototype );
    PIXI.DisplacementFilter.prototype.constructor = PIXI.DisplacementFilter;

    PIXI.DisplacementFilter.prototype.onTextureLoaded = function()
    {
        this.uniforms.mapDimensions.value.x = this.uniforms.displacementMap.value.width;
        this.uniforms.mapDimensions.value.y = this.uniforms.displacementMap.value.height;

        this.uniforms.displacementMap.value.baseTexture.off('loaded', this.boundLoadedFunction);
    };

    /**
     * The texture used for the displacemtent map * must be power of 2 texture at the moment
     *
     * @property map
     * @type Texture
     */
    Object.defineProperty(PIXI.DisplacementFilter.prototype, 'map', {
        get: function() {
            return this.uniforms.displacementMap.value;
        },
        set: function(value) {
            this.uniforms.displacementMap.value = value;
        }
    });

    /**
     * The multiplier used to scale the displacement result from the map calculation.
     *
     * @property scale
     * @type Point
     */
    Object.defineProperty(PIXI.DisplacementFilter.prototype, 'scale', {
        get: function() {
            return this.uniforms.scale.value;
        },
        set: function(value) {
            this.uniforms.scale.value = value;
        }
    });

    /**
     * The offset used to move the displacement map.
     *
     * @property offset
     * @type Point
     */
    Object.defineProperty(PIXI.DisplacementFilter.prototype, 'offset', {
        get: function() {
            return this.uniforms.offset.value;
        },
        set: function(value) {
            this.uniforms.offset.value = value;
        }
    });