bytev-charts/lib/plugin/three.js/examples/js/shaders/SMAAShader.js

基于echarts和JavaScript及ES6封装的一个可以直接调用的图表组件库，内置主题设计，简单快捷，且支持用户自定义配置； npm 安装方式: npm install bytev-charts 若启动提示还需额外install插件,则运行 npm install @babel/runtime-corejs2 即可;

import "core-js/modules/es.array.join.js";
console.warn("THREE.SMAAShader: As part of the transition to ES6 Modules, the files in 'examples/js' were deprecated in May 2020 (r117) and will be deleted in December 2020 (r124). You can find more information about developing using ES6 Modules in https://threejs.org/docs/#manual/en/introduction/Installation.");
/**
 * WebGL port of Subpixel Morphological Antialiasing (SMAA) v2.8
 * Preset: SMAA 1x Medium (with color edge detection)
 * https://github.com/iryoku/smaa/releases/tag/v2.8
 */

THREE.SMAAEdgesShader = {
  defines: {
    "SMAA_THRESHOLD": "0.1"
  },
  uniforms: {
    "tDiffuse": {
      value: null
    },
    "resolution": {
      value: new THREE.Vector2(1 / 1024, 1 / 512)
    }
  },
  vertexShader: ["uniform vec2 resolution;", "varying vec2 vUv;", "varying vec4 vOffset[ 3 ];", "void SMAAEdgeDetectionVS( vec2 texcoord ) {", "	vOffset[ 0 ] = texcoord.xyxy + resolution.xyxy * vec4( -1.0, 0.0, 0.0,  1.0 );", // WebGL port note: Changed sign in W component
  "	vOffset[ 1 ] = texcoord.xyxy + resolution.xyxy * vec4(  1.0, 0.0, 0.0, -1.0 );", // WebGL port note: Changed sign in W component
  "	vOffset[ 2 ] = texcoord.xyxy + resolution.xyxy * vec4( -2.0, 0.0, 0.0,  2.0 );", // WebGL port note: Changed sign in W component
  "}", "void main() {", "	vUv = uv;", "	SMAAEdgeDetectionVS( vUv );", "	gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );", "}"].join("\n"),
  fragmentShader: ["uniform sampler2D tDiffuse;", "varying vec2 vUv;", "varying vec4 vOffset[ 3 ];", "vec4 SMAAColorEdgeDetectionPS( vec2 texcoord, vec4 offset[3], sampler2D colorTex ) {", "	vec2 threshold = vec2( SMAA_THRESHOLD, SMAA_THRESHOLD );", // Calculate color deltas:
  "	vec4 delta;", "	vec3 C = texture2D( colorTex, texcoord ).rgb;", "	vec3 Cleft = texture2D( colorTex, offset[0].xy ).rgb;", "	vec3 t = abs( C - Cleft );", "	delta.x = max( max( t.r, t.g ), t.b );", "	vec3 Ctop = texture2D( colorTex, offset[0].zw ).rgb;", "	t = abs( C - Ctop );", "	delta.y = max( max( t.r, t.g ), t.b );", // We do the usual threshold:
  "	vec2 edges = step( threshold, delta.xy );", // Then discard if there is no edge:
  "	if ( dot( edges, vec2( 1.0, 1.0 ) ) == 0.0 )", "		discard;", // Calculate right and bottom deltas:
  "	vec3 Cright = texture2D( colorTex, offset[1].xy ).rgb;", "	t = abs( C - Cright );", "	delta.z = max( max( t.r, t.g ), t.b );", "	vec3 Cbottom  = texture2D( colorTex, offset[1].zw ).rgb;", "	t = abs( C - Cbottom );", "	delta.w = max( max( t.r, t.g ), t.b );", // Calculate the maximum delta in the direct neighborhood:
  "	float maxDelta = max( max( max( delta.x, delta.y ), delta.z ), delta.w );", // Calculate left-left and top-top deltas:
  "	vec3 Cleftleft  = texture2D( colorTex, offset[2].xy ).rgb;", "	t = abs( C - Cleftleft );", "	delta.z = max( max( t.r, t.g ), t.b );", "	vec3 Ctoptop = texture2D( colorTex, offset[2].zw ).rgb;", "	t = abs( C - Ctoptop );", "	delta.w = max( max( t.r, t.g ), t.b );", // Calculate the final maximum delta:
  "	maxDelta = max( max( maxDelta, delta.z ), delta.w );", // Local contrast adaptation in action:
  "	edges.xy *= step( 0.5 * maxDelta, delta.xy );", "	return vec4( edges, 0.0, 0.0 );", "}", "void main() {", "	gl_FragColor = SMAAColorEdgeDetectionPS( vUv, vOffset, tDiffuse );", "}"].join("\n")
};
THREE.SMAAWeightsShader = {
  defines: {
    "SMAA_MAX_SEARCH_STEPS": "8",
    "SMAA_AREATEX_MAX_DISTANCE": "16",
    "SMAA_AREATEX_PIXEL_SIZE": "( 1.0 / vec2( 160.0, 560.0 ) )",
    "SMAA_AREATEX_SUBTEX_SIZE": "( 1.0 / 7.0 )"
  },
  uniforms: {
    "tDiffuse": {
      value: null
    },
    "tArea": {
      value: null
    },
    "tSearch": {
      value: null
    },
    "resolution": {
      value: new THREE.Vector2(1 / 1024, 1 / 512)
    }
  },
  vertexShader: ["uniform vec2 resolution;", "varying vec2 vUv;", "varying vec4 vOffset[ 3 ];", "varying vec2 vPixcoord;", "void SMAABlendingWeightCalculationVS( vec2 texcoord ) {", "	vPixcoord = texcoord / resolution;", // We will use these offsets for the searches later on (see @PSEUDO_GATHER4):
  "	vOffset[ 0 ] = texcoord.xyxy + resolution.xyxy * vec4( -0.25, 0.125, 1.25, 0.125 );", // WebGL port note: Changed sign in Y and W components
  "	vOffset[ 1 ] = texcoord.xyxy + resolution.xyxy * vec4( -0.125, 0.25, -0.125, -1.25 );", // WebGL port note: Changed sign in Y and W components
  // And these for the searches, they indicate the ends of the loops:
  "	vOffset[ 2 ] = vec4( vOffset[ 0 ].xz, vOffset[ 1 ].yw ) + vec4( -2.0, 2.0, -2.0, 2.0 ) * resolution.xxyy * float( SMAA_MAX_SEARCH_STEPS );", "}", "void main() {", "	vUv = uv;", "	SMAABlendingWeightCalculationVS( vUv );", "	gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );", "}"].join("\n"),
  fragmentShader: ["#define SMAASampleLevelZeroOffset( tex, coord, offset ) texture2D( tex, coord + float( offset ) * resolution, 0.0 )", "uniform sampler2D tDiffuse;", "uniform sampler2D tArea;", "uniform sampler2D tSearch;", "uniform vec2 resolution;", "varying vec2 vUv;", "varying vec4 vOffset[3];", "varying vec2 vPixcoord;", "#if __VERSION__ == 100", "vec2 round( vec2 x ) {", "	return sign( x ) * floor( abs( x ) + 0.5 );", "}", "#endif", "float SMAASearchLength( sampler2D searchTex, vec2 e, float bias, float scale ) {", // Not required if searchTex accesses are set to point:
  // float2 SEARCH_TEX_PIXEL_SIZE = 1.0 / float2(66.0, 33.0);
  // e = float2(bias, 0.0) + 0.5 * SEARCH_TEX_PIXEL_SIZE +
  //     e * float2(scale, 1.0) * float2(64.0, 32.0) * SEARCH_TEX_PIXEL_SIZE;
  "	e.r = bias + e.r * scale;", "	return 255.0 * texture2D( searchTex, e, 0.0 ).r;", "}", "float SMAASearchXLeft( sampler2D edgesTex, sampler2D searchTex, vec2 texcoord, float end ) {",
  /**
  	* @PSEUDO_GATHER4
  	* This texcoord has been offset by (-0.25, -0.125) in the vertex shader to
  	* sample between edge, thus fetching four edges in a row.
  	* Sampling with different offsets in each direction allows to disambiguate
  	* which edges are active from the four fetched ones.
  	*/
  "	vec2 e = vec2( 0.0, 1.0 );", "	for ( int i = 0; i < SMAA_MAX_SEARCH_STEPS; i ++ ) {", // WebGL port note: Changed while to for
  "		e = texture2D( edgesTex, texcoord, 0.0 ).rg;", "		texcoord -= vec2( 2.0, 0.0 ) * resolution;", "		if ( ! ( texcoord.x > end && e.g > 0.8281 && e.r == 0.0 ) ) break;", "	}", // We correct the previous (-0.25, -0.125) offset we applied:
  "	texcoord.x += 0.25 * resolution.x;", // The searches are bias by 1, so adjust the coords accordingly:
  "	texcoord.x += resolution.x;", // Disambiguate the length added by the last step:
  "	texcoord.x += 2.0 * resolution.x;", // Undo last step
  "	texcoord.x -= resolution.x * SMAASearchLength(searchTex, e, 0.0, 0.5);", "	return texcoord.x;", "}", "float SMAASearchXRight( sampler2D edgesTex, sampler2D searchTex, vec2 texcoord, float end ) {", "	vec2 e = vec2( 0.0, 1.0 );", "	for ( int i = 0; i < SMAA_MAX_SEARCH_STEPS; i ++ ) {", // WebGL port note: Changed while to for
  "		e = texture2D( edgesTex, texcoord, 0.0 ).rg;", "		texcoord += vec2( 2.0, 0.0 ) * resolution;", "		if ( ! ( texcoord.x < end && e.g > 0.8281 && e.r == 0.0 ) ) break;", "	}", "	texcoord.x -= 0.25 * resolution.x;", "	texcoord.x -= resolution.x;", "	texcoord.x -= 2.0 * resolution.x;", "	texcoord.x += resolution.x * SMAASearchLength( searchTex, e, 0.5, 0.5 );", "	return texcoord.x;", "}", "float SMAASearchYUp( sampler2D edgesTex, sampler2D searchTex, vec2 texcoord, float end ) {", "	vec2 e = vec2( 1.0, 0.0 );", "	for ( int i = 0; i < SMAA_MAX_SEARCH_STEPS; i ++ ) {", // WebGL port note: Changed while to for
  "		e = texture2D( edgesTex, texcoord, 0.0 ).rg;", "		texcoord += vec2( 0.0, 2.0 ) * resolution;", // WebGL port note: Changed sign
  "		if ( ! ( texcoord.y > end && e.r > 0.8281 && e.g == 0.0 ) ) break;", "	}", "	texcoord.y -= 0.25 * resolution.y;", // WebGL port note: Changed sign
  "	texcoord.y -= resolution.y;", // WebGL port note: Changed sign
  "	texcoord.y -= 2.0 * resolution.y;", // WebGL port note: Changed sign
  "	texcoord.y += resolution.y * SMAASearchLength( searchTex, e.gr, 0.0, 0.5 );", // WebGL port note: Changed sign
  "	return texcoord.y;", "}", "float SMAASearchYDown( sampler2D edgesTex, sampler2D searchTex, vec2 texcoord, float end ) {", "	vec2 e = vec2( 1.0, 0.0 );", "	for ( int i = 0; i < SMAA_MAX_SEARCH_STEPS; i ++ ) {", // WebGL port note: Changed while to for
  "		e = texture2D( edgesTex, texcoord, 0.0 ).rg;", "		texcoord -= vec2( 0.0, 2.0 ) * resolution;", // WebGL port note: Changed sign
  "		if ( ! ( texcoord.y < end && e.r > 0.8281 && e.g == 0.0 ) ) break;", "	}", "	texcoord.y += 0.25 * resolution.y;", // WebGL port note: Changed sign
  "	texcoord.y += resolution.y;", // WebGL port note: Changed sign
  "	texcoord.y += 2.0 * resolution.y;", // WebGL port note: Changed sign
  "	texcoord.y -= resolution.y * SMAASearchLength( searchTex, e.gr, 0.5, 0.5 );", // WebGL port note: Changed sign
  "	return texcoord.y;", "}", "vec2 SMAAArea( sampler2D areaTex, vec2 dist, float e1, float e2, float offset ) {", // Rounding prevents precision errors of bilinear filtering:
  "	vec2 texcoord = float( SMAA_AREATEX_MAX_DISTANCE ) * round( 4.0 * vec2( e1, e2 ) ) + dist;", // We do a scale and bias for mapping to texel space:
  "	texcoord = SMAA_AREATEX_PIXEL_SIZE * texcoord + ( 0.5 * SMAA_AREATEX_PIXEL_SIZE );", // Move to proper place, according to the subpixel offset:
  "	texcoord.y += SMAA_AREATEX_SUBTEX_SIZE * offset;", "	return texture2D( areaTex, texcoord, 0.0 ).rg;", "}", "vec4 SMAABlendingWeightCalculationPS( vec2 texcoord, vec2 pixcoord, vec4 offset[ 3 ], sampler2D edgesTex, sampler2D areaTex, sampler2D searchTex, ivec4 subsampleIndices ) {", "	vec4 weights = vec4( 0.0, 0.0, 0.0, 0.0 );", "	vec2 e = texture2D( edgesTex, texcoord ).rg;", "	if ( e.g > 0.0 ) {", // Edge at north
  "		vec2 d;", // Find the distance to the left:
  "		vec2 coords;", "		coords.x = SMAASearchXLeft( edgesTex, searchTex, offset[ 0 ].xy, offset[ 2 ].x );", "		coords.y = offset[ 1 ].y;", // offset[1].y = texcoord.y - 0.25 * resolution.y (@CROSSING_OFFSET)
  "		d.x = coords.x;", // Now fetch the left crossing edges, two at a time using bilinear
  // filtering. Sampling at -0.25 (see @CROSSING_OFFSET) enables to
  // discern what value each edge has:
  "		float e1 = texture2D( edgesTex, coords, 0.0 ).r;", // Find the distance to the right:
  "		coords.x = SMAASearchXRight( edgesTex, searchTex, offset[ 0 ].zw, offset[ 2 ].y );", "		d.y = coords.x;", // We want the distances to be in pixel units (doing this here allow to
  // better interleave arithmetic and memory accesses):
  "		d = d / resolution.x - pixcoord.x;", // SMAAArea below needs a sqrt, as the areas texture is compressed
  // quadratically:
  "		vec2 sqrt_d = sqrt( abs( d ) );", // Fetch the right crossing edges:
  "		coords.y -= 1.0 * resolution.y;", // WebGL port note: Added
  "		float e2 = SMAASampleLevelZeroOffset( edgesTex, coords, ivec2( 1, 0 ) ).r;", // Ok, we know how this pattern looks like, now it is time for getting
  // the actual area:
  "		weights.rg = SMAAArea( areaTex, sqrt_d, e1, e2, float( subsampleIndices.y ) );", "	}", "	if ( e.r > 0.0 ) {", // Edge at west
  "		vec2 d;", // Find the distance to the top:
  "		vec2 coords;", "		coords.y = SMAASearchYUp( edgesTex, searchTex, offset[ 1 ].xy, offset[ 2 ].z );", "		coords.x = offset[ 0 ].x;", // offset[1].x = texcoord.x - 0.25 * resolution.x;
  "		d.x = coords.y;", // Fetch the top crossing edges:
  "		float e1 = texture2D( edgesTex, coords, 0.0 ).g;", // Find the distance to the bottom:
  "		coords.y = SMAASearchYDown( edgesTex, searchTex, offset[ 1 ].zw, offset[ 2 ].w );", "		d.y = coords.y;", // We want the distances to be in pixel units:
  "		d = d / resolution.y - pixcoord.y;", // SMAAArea below needs a sqrt, as the areas texture is compressed
  // quadratically:
  "		vec2 sqrt_d = sqrt( abs( d ) );", // Fetch the bottom crossing edges:
  "		coords.y -= 1.0 * resolution.y;", // WebGL port note: Added
  "		float e2 = SMAASampleLevelZeroOffset( edgesTex, coords, ivec2( 0, 1 ) ).g;", // Get the area for this direction:
  "		weights.ba = SMAAArea( areaTex, sqrt_d, e1, e2, float( subsampleIndices.x ) );", "	}", "	return weights;", "}", "void main() {", "	gl_FragColor = SMAABlendingWeightCalculationPS( vUv, vPixcoord, vOffset, tDiffuse, tArea, tSearch, ivec4( 0.0 ) );", "}"].join("\n")
};
THREE.SMAABlendShader = {
  uniforms: {
    "tDiffuse": {
      value: null
    },
    "tColor": {
      value: null
    },
    "resolution": {
      value: new THREE.Vector2(1 / 1024, 1 / 512)
    }
  },
  vertexShader: ["uniform vec2 resolution;", "varying vec2 vUv;", "varying vec4 vOffset[ 2 ];", "void SMAANeighborhoodBlendingVS( vec2 texcoord ) {", "	vOffset[ 0 ] = texcoord.xyxy + resolution.xyxy * vec4( -1.0, 0.0, 0.0, 1.0 );", // WebGL port note: Changed sign in W component
  "	vOffset[ 1 ] = texcoord.xyxy + resolution.xyxy * vec4( 1.0, 0.0, 0.0, -1.0 );", // WebGL port note: Changed sign in W component
  "}", "void main() {", "	vUv = uv;", "	SMAANeighborhoodBlendingVS( vUv );", "	gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );", "}"].join("\n"),
  fragmentShader: ["uniform sampler2D tDiffuse;", "uniform sampler2D tColor;", "uniform vec2 resolution;", "varying vec2 vUv;", "varying vec4 vOffset[ 2 ];", "vec4 SMAANeighborhoodBlendingPS( vec2 texcoord, vec4 offset[ 2 ], sampler2D colorTex, sampler2D blendTex ) {", // Fetch the blending weights for current pixel:
  "	vec4 a;", "	a.xz = texture2D( blendTex, texcoord ).xz;", "	a.y = texture2D( blendTex, offset[ 1 ].zw ).g;", "	a.w = texture2D( blendTex, offset[ 1 ].xy ).a;", // Is there any blending weight with a value greater than 0.0?
  "	if ( dot(a, vec4( 1.0, 1.0, 1.0, 1.0 )) < 1e-5 ) {", "		return texture2D( colorTex, texcoord, 0.0 );", "	} else {", // Up to 4 lines can be crossing a pixel (one through each edge). We
  // favor blending by choosing the line with the maximum weight for each
  // direction:
  "		vec2 offset;", "		offset.x = a.a > a.b ? a.a : -a.b;", // left vs. right
  "		offset.y = a.g > a.r ? -a.g : a.r;", // top vs. bottom // WebGL port note: Changed signs
  // Then we go in the direction that has the maximum weight:
  "		if ( abs( offset.x ) > abs( offset.y )) {", // horizontal vs. vertical
  "			offset.y = 0.0;", "		} else {", "			offset.x = 0.0;", "		}", // Fetch the opposite color and lerp by hand:
  "		vec4 C = texture2D( colorTex, texcoord, 0.0 );", "		texcoord += sign( offset ) * resolution;", "		vec4 Cop = texture2D( colorTex, texcoord, 0.0 );", "		float s = abs( offset.x ) > abs( offset.y ) ? abs( offset.x ) : abs( offset.y );", // WebGL port note: Added gamma correction
  "		C.xyz = pow(C.xyz, vec3(2.2));", "		Cop.xyz = pow(Cop.xyz, vec3(2.2));", "		vec4 mixed = mix(C, Cop, s);", "		mixed.xyz = pow(mixed.xyz, vec3(1.0 / 2.2));", "		return mixed;", "	}", "}", "void main() {", "	gl_FragColor = SMAANeighborhoodBlendingPS( vUv, vOffset, tColor, tDiffuse );", "}"].join("\n")
};