LineMaterial = (function () { /** * parameters = { * color: , * linewidth: , * dashed: , * dashScale: , * dashSize: , * dashOffset: , * gapSize: , * resolution: , // to be set by renderer * } */ THREE.UniformsLib.line = { worldUnits: { value: 1 }, linewidth: { value: 1 }, resolution: { value: new THREE.Vector2(1, 1) }, dashOffset: { value: 0 }, dashScale: { value: 1 }, dashSize: { value: 1 }, gapSize: { value: 1 } // todo FIX - maybe change to totalSize }; THREE.ShaderLib["line"] = { uniforms: THREE.UniformsUtils.merge([ THREE.UniformsLib.common, THREE.UniformsLib.fog, THREE.UniformsLib.line ]), vertexShader: /* glsl */ ` #include #include #include #include #include uniform float linewidth; uniform vec2 resolution; attribute vec3 instanceStart; attribute vec3 instanceEnd; attribute vec3 instanceColorStart; attribute vec3 instanceColorEnd; #ifdef WORLD_UNITS varying vec4 worldPos; varying vec3 worldStart; varying vec3 worldEnd; #ifdef USE_DASH varying vec2 vUv; #endif #else varying vec2 vUv; #endif #ifdef USE_DASH uniform float dashScale; attribute float instanceDistanceStart; attribute float instanceDistanceEnd; varying float vLineDistance; #endif void trimSegment( const in vec4 start, inout vec4 end ) { // trim end segment so it terminates between the camera plane and the near plane // conservative estimate of the near plane float a = projectionMatrix[ 2 ][ 2 ]; // 3nd entry in 3th column float b = projectionMatrix[ 3 ][ 2 ]; // 3nd entry in 4th column float nearEstimate = - 0.5 * b / a; float alpha = ( nearEstimate - start.z ) / ( end.z - start.z ); end.xyz = mix( start.xyz, end.xyz, alpha ); } void main() { #ifdef USE_COLOR vColor.xyz = ( position.y < 0.5 ) ? instanceColorStart : instanceColorEnd; #endif #ifdef USE_DASH vLineDistance = ( position.y < 0.5 ) ? dashScale * instanceDistanceStart : dashScale * instanceDistanceEnd; vUv = uv; #endif float aspect = resolution.x / resolution.y; // camera space vec4 start = modelViewMatrix * vec4( instanceStart, 1.0 ); vec4 end = modelViewMatrix * vec4( instanceEnd, 1.0 ); #ifdef WORLD_UNITS worldStart = start.xyz; worldEnd = end.xyz; #else vUv = uv; #endif // special case for perspective projection, and segments that terminate either in, or behind, the camera plane // clearly the gpu firmware has a way of addressing this issue when projecting into ndc space // but we need to perform ndc-space calculations in the shader, so we must address this issue directly // perhaps there is a more elegant solution -- WestLangley bool perspective = ( projectionMatrix[ 2 ][ 3 ] == - 1.0 ); // 4th entry in the 3rd column if ( perspective ) { if ( start.z < 0.0 && end.z >= 0.0 ) { trimSegment( start, end ); } else if ( end.z < 0.0 && start.z >= 0.0 ) { trimSegment( end, start ); } } // clip space vec4 clipStart = projectionMatrix * start; vec4 clipEnd = projectionMatrix * end; // ndc space vec3 ndcStart = clipStart.xyz / clipStart.w; vec3 ndcEnd = clipEnd.xyz / clipEnd.w; // direction vec2 dir = ndcEnd.xy - ndcStart.xy; // account for clip-space aspect ratio dir.x *= aspect; dir = normalize( dir ); #ifdef WORLD_UNITS // get the offset direction as perpendicular to the view vector vec3 worldDir = normalize( end.xyz - start.xyz ); vec3 offset; if ( position.y < 0.5 ) { offset = normalize( cross( start.xyz, worldDir ) ); } else { offset = normalize( cross( end.xyz, worldDir ) ); } // sign flip if ( position.x < 0.0 ) offset *= - 1.0; float forwardOffset = dot( worldDir, vec3( 0.0, 0.0, 1.0 ) ); // don't extend the line if we're rendering dashes because we // won't be rendering the endcaps #ifndef USE_DASH // extend the line bounds to encompass endcaps start.xyz += - worldDir * linewidth * 0.5; end.xyz += worldDir * linewidth * 0.5; // shift the position of the quad so it hugs the forward edge of the line offset.xy -= dir * forwardOffset; offset.z += 0.5; #endif // endcaps if ( position.y > 1.0 || position.y < 0.0 ) { offset.xy += dir * 2.0 * forwardOffset; } // adjust for linewidth offset *= linewidth * 0.5; // set the world position worldPos = ( position.y < 0.5 ) ? start : end; worldPos.xyz += offset; // project the worldpos vec4 clip = projectionMatrix * worldPos; // shift the depth of the projected points so the line // segments overlap neatly vec3 clipPose = ( position.y < 0.5 ) ? ndcStart : ndcEnd; clip.z = clipPose.z * clip.w; #else vec2 offset = vec2( dir.y, - dir.x ); // undo aspect ratio adjustment dir.x /= aspect; offset.x /= aspect; // sign flip if ( position.x < 0.0 ) offset *= - 1.0; // endcaps if ( position.y < 0.0 ) { offset += - dir; } else if ( position.y > 1.0 ) { offset += dir; } // adjust for linewidth offset *= linewidth; // adjust for clip-space to screen-space conversion // maybe resolution should be based on viewport ... offset /= resolution.y; // select end vec4 clip = ( position.y < 0.5 ) ? clipStart : clipEnd; // back to clip space offset *= clip.w; clip.xy += offset; #endif gl_Position = clip; vec4 mvPosition = ( position.y < 0.5 ) ? start : end; // this is an approximation #include #include #include } `, fragmentShader: /* glsl */ ` uniform vec3 diffuse; uniform float opacity; uniform float linewidth; #ifdef USE_DASH uniform float dashOffset; uniform float dashSize; uniform float gapSize; #endif varying float vLineDistance; #ifdef WORLD_UNITS varying vec4 worldPos; varying vec3 worldStart; varying vec3 worldEnd; #ifdef USE_DASH varying vec2 vUv; #endif #else varying vec2 vUv; #endif #include #include #include #include #include vec2 closestLineToLine(vec3 p1, vec3 p2, vec3 p3, vec3 p4) { float mua; float mub; vec3 p13 = p1 - p3; vec3 p43 = p4 - p3; vec3 p21 = p2 - p1; float d1343 = dot( p13, p43 ); float d4321 = dot( p43, p21 ); float d1321 = dot( p13, p21 ); float d4343 = dot( p43, p43 ); float d2121 = dot( p21, p21 ); float denom = d2121 * d4343 - d4321 * d4321; float numer = d1343 * d4321 - d1321 * d4343; mua = numer / denom; mua = clamp( mua, 0.0, 1.0 ); mub = ( d1343 + d4321 * ( mua ) ) / d4343; mub = clamp( mub, 0.0, 1.0 ); return vec2( mua, mub ); } void main() { #include #ifdef USE_DASH if ( vUv.y < - 1.0 || vUv.y > 1.0 ) discard; // discard endcaps if ( mod( vLineDistance + dashOffset, dashSize + gapSize ) > dashSize ) discard; // todo - FIX #endif float alpha = opacity; #ifdef WORLD_UNITS // Find the closest points on the view ray and the line segment vec3 rayEnd = normalize( worldPos.xyz ) * 1e5; vec3 lineDir = worldEnd - worldStart; vec2 params = closestLineToLine( worldStart, worldEnd, vec3( 0.0, 0.0, 0.0 ), rayEnd ); vec3 p1 = worldStart + lineDir * params.x; vec3 p2 = rayEnd * params.y; vec3 delta = p1 - p2; float len = length( delta ); float norm = len / linewidth; #ifndef USE_DASH #ifdef USE_ALPHA_TO_COVERAGE float dnorm = fwidth( norm ); alpha = 1.0 - smoothstep( 0.5 - dnorm, 0.5 + dnorm, norm ); #else if ( norm > 0.5 ) { discard; } #endif #endif #else #ifdef USE_ALPHA_TO_COVERAGE // artifacts appear on some hardware if a derivative is taken within a conditional float a = vUv.x; float b = ( vUv.y > 0.0 ) ? vUv.y - 1.0 : vUv.y + 1.0; float len2 = a * a + b * b; float dlen = fwidth( len2 ); if ( abs( vUv.y ) > 1.0 ) { alpha = 1.0 - smoothstep( 1.0 - dlen, 1.0 + dlen, len2 ); } #else if ( abs( vUv.y ) > 1.0 ) { float a = vUv.x; float b = ( vUv.y > 0.0 ) ? vUv.y - 1.0 : vUv.y + 1.0; float len2 = a * a + b * b; if ( len2 > 1.0 ) discard; } #endif #endif vec4 diffuseColor = vec4( diffuse, alpha ); #include #include gl_FragColor = vec4( diffuseColor.rgb, alpha ); #include #include #include #include } ` }; class LineMaterial extends THREE.ShaderMaterial { constructor(parameters) { super({ type: "LineMaterial", uniforms: THREE.UniformsUtils.clone(THREE.ShaderLib["line"].uniforms), vertexShader: THREE.ShaderLib["line"].vertexShader, fragmentShader: THREE.ShaderLib["line"].fragmentShader, clipping: true // required for clipping support }); this.isLineMaterial = true; Object.defineProperties(this, { color: { enumerable: true, get: function () { return this.uniforms.diffuse.value; }, set: function (value) { this.uniforms.diffuse.value = value; } }, worldUnits: { enumerable: true, get: function () { return "WORLD_UNITS" in this.defines; }, set: function (value) { if (value === true) { this.defines.WORLD_UNITS = ""; } else { delete this.defines.WORLD_UNITS; } } }, linewidth: { enumerable: true, get: function () { return this.uniforms.linewidth.value; }, set: function (value) { this.uniforms.linewidth.value = value; } }, dashed: { enumerable: true, get: function () { return Boolean("USE_DASH" in this.defines); }, set(value) { if (Boolean(value) !== Boolean("USE_DASH" in this.defines)) { this.needsUpdate = true; } if (value === true) { this.defines.USE_DASH = ""; } else { delete this.defines.USE_DASH; } } }, dashScale: { enumerable: true, get: function () { return this.uniforms.dashScale.value; }, set: function (value) { this.uniforms.dashScale.value = value; } }, dashSize: { enumerable: true, get: function () { return this.uniforms.dashSize.value; }, set: function (value) { this.uniforms.dashSize.value = value; } }, dashOffset: { enumerable: true, get: function () { return this.uniforms.dashOffset.value; }, set: function (value) { this.uniforms.dashOffset.value = value; } }, gapSize: { enumerable: true, get: function () { return this.uniforms.gapSize.value; }, set: function (value) { this.uniforms.gapSize.value = value; } }, opacity: { enumerable: true, get: function () { return this.uniforms.opacity.value; }, set: function (value) { this.uniforms.opacity.value = value; } }, resolution: { enumerable: true, get: function () { return this.uniforms.resolution.value; }, set: function (value) { this.uniforms.resolution.value.copy(value); } }, alphaToCoverage: { enumerable: true, get: function () { return Boolean("USE_ALPHA_TO_COVERAGE" in this.defines); }, set: function (value) { if ( Boolean(value) !== Boolean("USE_ALPHA_TO_COVERAGE" in this.defines) ) { this.needsUpdate = true; } if (value === true) { this.defines.USE_ALPHA_TO_COVERAGE = ""; this.extensions.derivatives = true; } else { delete this.defines.USE_ALPHA_TO_COVERAGE; this.extensions.derivatives = false; } } } }); this.setValues(parameters); } } return LineMaterial; })()

Purpose-built for displays of data