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@cesium/engine

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CesiumJS is a JavaScript library for creating 3D globes and 2D maps in a web browser without a plugin.

cesium.com/cesiumjs/

CesiumGS/cesium

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//This file is automatically rebuilt by the Cesium build process. export default "void verticalExaggerationStage(\n\ inout ProcessedAttributes attributes\n\ ) {\n\ // Compute the distance from the camera to the local center of curvature.\n\ vec4 vertexPositionENU = czm_modelToEnu * vec4(attributes.positionMC, 1.0);\n\ vec2 vertexAzimuth = normalize(vertexPositionENU.xy);\n\ // Curvature = 1 / radius of curvature.\n\ float azimuthalCurvature = dot(vertexAzimuth * vertexAzimuth, czm_eyeEllipsoidCurvature);\n\ float eyeToCenter = 1.0 / azimuthalCurvature + czm_eyeHeight;\n\ \n\ // Compute the approximate ellipsoid normal at the vertex position.\n\ // Uses a circular approximation for the Earth curvature along the geodesic.\n\ vec3 vertexPositionEC = (czm_modelView * vec4(attributes.positionMC, 1.0)).xyz;\n\ vec3 centerToVertex = eyeToCenter * czm_eyeEllipsoidNormalEC + vertexPositionEC;\n\ vec3 vertexNormal = normalize(centerToVertex);\n\ \n\ // Estimate the (sine of the) angle between the camera direction and the vertex normal\n\ float verticalDistance = dot(vertexPositionEC, czm_eyeEllipsoidNormalEC);\n\ float horizontalDistance = length(vertexPositionEC - verticalDistance * czm_eyeEllipsoidNormalEC);\n\ float sinTheta = horizontalDistance / (eyeToCenter + verticalDistance);\n\ bool isSmallAngle = clamp(sinTheta, 0.0, 0.05) == sinTheta;\n\ \n\ // Approximate the change in height above the ellipsoid, from camera to vertex position.\n\ float exactVersine = 1.0 - dot(czm_eyeEllipsoidNormalEC, vertexNormal);\n\ float smallAngleVersine = 0.5 * sinTheta * sinTheta;\n\ float versine = isSmallAngle ? smallAngleVersine : exactVersine;\n\ float dHeight = dot(vertexPositionEC, vertexNormal) - eyeToCenter * versine;\n\ float vertexHeight = czm_eyeHeight + dHeight;\n\ \n\ // Transform the approximate vertex normal to model coordinates.\n\ vec3 vertexNormalMC = (czm_inverseModelView * vec4(vertexNormal, 0.0)).xyz;\n\ vertexNormalMC = normalize(vertexNormalMC);\n\ \n\ // Compute the exaggeration and apply it along the approximate vertex normal.\n\ float stretch = u_verticalExaggerationAndRelativeHeight.x;\n\ float shift = u_verticalExaggerationAndRelativeHeight.y;\n\ float exaggeration = (vertexHeight - shift) * (stretch - 1.0);\n\ attributes.positionMC += exaggeration * vertexNormalMC;\n\ }\n\ ";