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World Wind is a collection of components that interactively display 3D geographic information within Java applications or applets.
/*
* Copyright (C) 2012 United States Government as represented by the Administrator of the
* National Aeronautics and Space Administration.
* All Rights Reserved.
*/
package gov.nasa.worldwind.render;
import com.jogamp.common.nio.Buffers;
import gov.nasa.worldwind.*;
import gov.nasa.worldwind.avlist.AVKey;
import gov.nasa.worldwind.cache.GpuResourceCache;
import gov.nasa.worldwind.exception.WWRuntimeException;
import gov.nasa.worldwind.geom.*;
import gov.nasa.worldwind.geom.Box;
import gov.nasa.worldwind.globes.Globe;
import gov.nasa.worldwind.ogc.kml.impl.KMLExportUtil;
import gov.nasa.worldwind.terrain.Terrain;
import gov.nasa.worldwind.util.*;
import javax.media.opengl.*;
import javax.media.opengl.glu.GLU;
import javax.xml.stream.*;
import java.io.*;
import java.nio.*;
import java.util.*;
/**
* /** A 3D polygon. The polygon may be complex with multiple internal but not intersecting contours.
*
* Polygons are safe to share among World Windows. They should not be shared among layers in the same World Window.
*
* In order to support simultaneous use of this shape with multiple globes (windows), this shape maintains a cache of
* data computed relative to each globe. During rendering, the data for the currently active globe, as indicated in the
* draw context, is made current. Subsequently called methods rely on the existence of this current data cache entry.
*
* @author tag
* @version $Id: Polygon.java 1171 2013-02-11 21:45:02Z dcollins $
*/
public class Polygon extends AbstractShape
{
// TODO: Merge texture coordinates into the vertex+normal buffer rather than specifying them in a separate buffer.
// TODO: Tessellate polygon's interior to follow globe curvature when in ABSOLUTE altitude mode.
/**
* This class holds globe-specific data for this shape. It's managed via the shape-data cache in {@link
* gov.nasa.worldwind.render.AbstractShape.AbstractShapeData}.
*/
protected static class ShapeData extends AbstractShapeData implements Iterable
{
/** This class holds the per-globe data for this shape. */
protected List boundaries = new ArrayList();
/** The rotation matrix for this shape data. */
protected Matrix rotationMatrix; // will vary among globes
/**
* The vertex data buffer for this shape data. The first half contains vertex coordinates, the second half
* contains normals.
*/
protected FloatBuffer coordBuffer; // contains boundary vertices in first half and normals in second half
/** The slice of the coordBuffer that contains normals. */
protected FloatBuffer normalBuffer;
/** The index of the first normal in the coordBuffer. */
protected int normalBufferPosition;
/** This shape's tessellation indices. */
protected GLUTessellatorSupport.CollectIndexListsCallback cb; // the tessellated polygon indices
/**
* The indices identifying the cap vertices in a shape data's vertex buffer. Determined when this shape is
* tessellated, which occurs only once unless the shape's boundaries are re-specified.
*/
protected IntBuffer interiorIndicesBuffer;
/** Indicates whether a tessellation error occurred. No more attempts to tessellate will be made if set to true. */
protected boolean tessellationError = false; // set to true if the tessellator fails
/** Indicates whether the index buffer needs to be filled because a new buffer is used or some other reason. */
protected boolean refillIndexBuffer = true; // set to true if the index buffer needs to be refilled
/**
* Indicates whether the index buffer's VBO needs to be filled because a new buffer is used or some other
* reason.
*/
protected boolean refillIndexVBO = true; // set to true if the index VBO needs to be refilled
/**
* Construct a cache entry using the boundaries of this shape.
*
* @param dc the current draw context.
* @param shape this shape.
*/
public ShapeData(DrawContext dc, Polygon shape)
{
super(dc, shape.minExpiryTime, shape.maxExpiryTime);
if (shape.boundaries.size() < 1)
{
// add a placeholder for the outer boundary
this.boundaries.add(new BoundaryInfo(new ArrayList()));
return;
}
// Copy the shape's boundaries.
for (List boundary : shape.boundaries)
{
this.boundaries.add(new BoundaryInfo(boundary));
}
}
/**
* Returns the boundary information for this shape data's outer boundary.
*
* @return this shape data's outer boundary info.
*/
protected BoundaryInfo getOuterBoundaryInfo()
{
return this.boundaries.get(0);
}
public Iterator iterator()
{
return this.boundaries.iterator();
}
/**
* Returns this shape data's rotation matrix, if there is one.
*
* @return this shape data's rotation matrix, or null if there isn't one.
*/
public Matrix getRotationMatrix()
{
return this.rotationMatrix;
}
/**
* Specifies this shape data's rotation matrix.
*
* @param matrix the new rotation matrix.
*/
public void setRotationMatrix(Matrix matrix)
{
this.rotationMatrix = matrix;
}
}
protected AbstractShapeData createCacheEntry(DrawContext dc)
{
return new ShapeData(dc, this);
}
/**
* Returns the current shape data cache entry.
*
* @return the current data cache entry.
*/
protected ShapeData getCurrent()
{
return (ShapeData) this.getCurrentData();
}
/** Holds information for each contour of the polygon. The vertex values are updated at every geometry regeneration. */
protected static class BoundaryInfo
{
/** The shape's boundary positions. */
protected List positions;
/** The shape's computed vertices, arranged in one array. */
protected Vec4[] vertices; // TODO: eliminate need for this; use the vertex buffer instead
/** The shape's computed vertices, arranged in a buffer. */
protected FloatBuffer vertexBuffer; // vertices passed to OpenGL
/**
* Construct an instance for a specified boundary.
*
* @param positions the boundary positions.
*/
public BoundaryInfo(List positions)
{
this.positions = positions;
}
}
/**
* This static hash map holds the vertex indices that define the shape's visual outline. The contents depend only on
* the number of locations in the source polygon, so they can be reused by all shapes with the same location count.
*/
protected static HashMap edgeIndexBuffers = new HashMap();
/** Indicates the number of vertices that must be present in order for VBOs to be used to render this shape. */
protected static final int VBO_THRESHOLD = Configuration.getIntegerValue(AVKey.VBO_THRESHOLD, 30);
/**
* The location of each vertex in this shape's boundaries. There is one list per boundary. There is always an entry
* for the outer boundary, but its list is empty if an outer boundary has not been specified.
*/
protected List> boundaries; // the defining locations or positions of the boundary
/** The total number of positions in the entire polygon. */
protected int numPositions;
/** The image source for this shape's texture, if any. */
protected Object imageSource; // image source for the optional texture
/** If an image source was specified, this is the WWTexture form. */
protected WWTexture texture; // an optional texture for the base polygon
/** This shape's rotation, in degrees positive counterclockwise. */
protected Double rotation; // in degrees; positive is CCW
/** This shape's texture coordinates. */
protected FloatBuffer textureCoordsBuffer; // texture coords if texturing
// Fields used in intersection calculations
/** The terrain used in the most recent intersection calculations. */
protected Terrain previousIntersectionTerrain;
/** The globe state key for the globe used in the most recent intersection calculation. */
protected Object previousIntersectionGlobeStateKey;
/** The shape data used for the previous intersection calculation. */
protected ShapeData previousIntersectionShapeData;
/** Construct a polygon with an empty outer boundary. */
public Polygon()
{
this.boundaries = new ArrayList>();
this.boundaries.add(new ArrayList()); // placeholder for outer boundary
}
/**
* Construct a polygon for a specified outer boundary.
*
* @param corners the list of locations defining the polygon.
*
* @throws IllegalArgumentException if the location list is null.
*/
public Polygon(Iterable corners)
{
this(); // to initialize the instance
if (corners == null)
{
String message = Logging.getMessage("nullValue.PositionsListIsNull");
Logging.logger().severe(message);
throw new IllegalArgumentException(message);
}
this.setOuterBoundary(corners);
}
/**
* Construct a polygon for a specified list of outer-boundary positions.
*
* @param corners the list of positions -- latitude longitude and altitude -- defining the polygon. The current
* altitude mode determines whether the positions are considered relative to mean sea level (they are
* "absolute") or the ground elevation at the associated latitude and longitude.
*
* @throws IllegalArgumentException if the position list is null.
*/
public Polygon(Position.PositionList corners)
{
this(); // to initialize the boundaries
if (corners == null)
{
String message = Logging.getMessage("nullValue.PositionsListIsNull");
Logging.logger().severe(message);
throw new IllegalArgumentException(message);
}
this.setOuterBoundary(corners.list);
}
@Override
protected void initialize()
{
// Nothing unique to initialize in this class.
}
/** Void any computed data. Called when a factor affecting the computed data is changed. */
protected void reset()
{
// Assumes that the boundary lists have already been established.
for (List boundary : this.boundaries)
{
if (boundary == null || boundary.size() < 3)
continue;
//noinspection StringEquality
if (WWMath.computeWindingOrderOfLocations(boundary) != AVKey.COUNTER_CLOCKWISE)
Collections.reverse(boundary);
}
this.numPositions = this.countPositions();
this.previousIntersectionShapeData = null;
this.previousIntersectionTerrain = null;
this.previousIntersectionGlobeStateKey = null;
super.reset(); // removes all shape-data cache entries
}
/**
* Counts the total number of positions in this shape, including all positions in all boundaries.
*
* @return the number of positions in this shape.
*/
protected int countPositions()
{
int count = 0;
for (List boundary : this.boundaries)
{
count += boundary.size();
}
return count;
}
/**
* Returns the list of positions defining this polygon's outer boundary.
*
* @return this polygon's outer boundary positions. The list may be empty but will not be null.
*/
public Iterable getOuterBoundary()
{
return this.outerBoundary();
}
/**
* Returns a reference to the outer boundary of this polygon.
*
* @return this polygon's outer boundary. The list may be empty but will not be null.
*/
protected List outerBoundary()
{
return this.boundaries.get(0);
}
protected boolean isOuterBoundaryValid()
{
return this.boundaries.size() > 0 && this.boundaries.get(0).size() > 2;
}
/**
* Specifies the latitude, longitude and altitude of the outer boundary positions defining this polygon.
*
* @param corners this polygon's positions. A copy of the list is made and retained, and a duplicate of the first
* position is appended to the copy if the first and last positions are not identical.
*
* @throws IllegalArgumentException if the location list is null or contains fewer than three locations.
*/
public void setOuterBoundary(Iterable corners)
{
if (corners == null)
{
String message = Logging.getMessage("nullValue.PositionsListIsNull");
Logging.logger().severe(message);
throw new IllegalArgumentException(message);
}
this.boundaries.set(0, this.fillBoundary(corners));
this.reset();
}
/**
* Copies a boundary's positions to this shape's internal boundary list. Closes the boundary if it's not already
* closed.
*
* @param corners the boundary's positions.
*
* @return a list of the boundary positions.
*/
protected List fillBoundary(Iterable corners)
{
ArrayList list = new ArrayList();
for (Position corner : corners)
{
if (corner != null)
list.add(corner);
}
if (list.size() < 3)
{
String message = Logging.getMessage("generic.InsufficientPositions");
Logging.logger().severe(message);
throw new IllegalArgumentException(message);
}
// Close the list if not already closed.
if (list.size() > 0 && !list.get(0).equals(list.get(list.size() - 1)))
list.add(list.get(0));
list.trimToSize();
return list;
}
/**
* Add an inner boundary to this polygon. A duplicate of the first position is appended to the list if the list's
* last position is not identical to the first.
*
* @param corners the new boundary positions. A copy of the list is created and retained, and a duplicate of the
* first position is added to the list if the first and last positions are not identical.
*
* @throws IllegalArgumentException if the location list is null or contains fewer than three locations.
*/
public void addInnerBoundary(Iterable corners)
{
if (corners == null)
{
String message = Logging.getMessage("nullValue.PositionsListIsNull");
Logging.logger().severe(message);
throw new IllegalArgumentException(message);
}
this.boundaries.add(this.fillBoundary(corners));
this.reset();
}
/**
* Returns this shape's boundaries.
*
* @return this shape's boundaries.
*/
public List> getBoundaries()
{
return this.boundaries;
}
/**
* Returns this polygon's texture image source.
*
* @return the texture image source, or null if no source has been specified.
*/
public Object getTextureImageSource()
{
return this.imageSource;
}
/**
* Get the texture applied to this polygon. The texture is loaded on a background thread. This method will return
* null until the texture has been loaded.
*
* @return the texture, or null if there is no texture or the texture is not yet available.
*/
protected WWTexture getTexture()
{
return this.texture;
}
/**
* Returns the texture coordinates for this polygon.
*
* @return the texture coordinates, or null if no texture coordinates have been specified.
*/
public float[] getTextureCoords()
{
if (this.textureCoordsBuffer == null)
return null;
float[] retCoords = new float[this.textureCoordsBuffer.limit()];
this.textureCoordsBuffer.get(retCoords, 0, retCoords.length);
return retCoords;
}
/**
* Specifies the texture to apply to this polygon.
*
* @param imageSource the texture image source. May be a {@link String} identifying a file path or URL, a {@link
* File}, or a {@link java.net.URL}.
* @param texCoords the (s, t) texture coordinates aligning the image to the polygon. There must be one texture
* coordinate pair, (s, t), for each polygon location in the polygon's outer boundary.
* @param texCoordCount the number of texture coordinates, (s, v) pairs, specified.
*
* @throws IllegalArgumentException if the image source is not null and either the texture coordinates are null or
* inconsistent with the specified texture-coordinate count, or there are fewer
* than three texture coordinate pairs.
*/
public void setTextureImageSource(Object imageSource, float[] texCoords, int texCoordCount)
{
if (imageSource == null)
{
this.texture = null;
this.textureCoordsBuffer = null;
return;
}
if (texCoords == null)
{
String message = Logging.getMessage("generic.ListIsEmpty");
Logging.logger().severe(message);
throw new IllegalArgumentException(message);
}
if (texCoordCount < 3 || texCoords.length < 2 * texCoordCount)
{
String message = Logging.getMessage("generic.InsufficientPositions");
Logging.logger().severe(message);
throw new IllegalArgumentException(message);
}
this.imageSource = imageSource;
this.texture = this.makeTexture(this.imageSource);
// Determine whether the tex-coord list needs to be closed.
boolean closeIt = texCoords[0] != texCoords[texCoordCount - 2] || texCoords[1] != texCoords[texCoordCount - 1];
int size = 2 * (texCoordCount + (closeIt ? 1 : 0));
if (this.textureCoordsBuffer == null || this.textureCoordsBuffer.capacity() < size)
{
this.textureCoordsBuffer = Buffers.newDirectFloatBuffer(size);
}
else
{
this.textureCoordsBuffer.limit(this.textureCoordsBuffer.capacity());
this.textureCoordsBuffer.rewind();
}
for (int i = 0; i < 2 * texCoordCount; i++)
{
this.textureCoordsBuffer.put(texCoords[i]);
}
if (closeIt)
{
this.textureCoordsBuffer.put(this.textureCoordsBuffer.get(0));
this.textureCoordsBuffer.put(this.textureCoordsBuffer.get(1));
}
}
public Position getReferencePosition()
{
if (this.referencePosition != null)
return this.referencePosition;
if (this.outerBoundary().size() > 0)
this.referencePosition = this.outerBoundary().get(0);
return this.referencePosition;
}
/**
* Indicates the amount of rotation applied to this polygon.
*
* @return the rotation in degrees, or null if no rotation is specified.
*/
public Double getRotation()
{
return this.rotation;
}
/**
* Specifies the amount of rotation applied to this polygon. Positive rotation is counter-clockwise.
*
* @param rotation the amount of rotation to apply, in degrees, or null to apply no rotation.
*/
public void setRotation(Double rotation)
{
this.rotation = rotation;
this.reset();
}
public Extent getExtent(Globe globe, double verticalExaggeration)
{
// See if we've cached an extent associated with the globe.
Extent extent = super.getExtent(globe, verticalExaggeration);
if (extent != null)
return extent;
return super.computeExtentFromPositions(globe, verticalExaggeration, this.getOuterBoundary());
}
/**
* Computes the Cartesian extent of a polygon boundary.
*
* @param boundary The boundary to compute the extent for.
* @param refPoint the shape's reference point.
*
* @return the boundary's extent. Returns null if the boundary's vertices have not been computed.
*/
protected Extent computeExtent(BoundaryInfo boundary, Vec4 refPoint)
{
if (boundary == null || boundary.vertices == null)
return null;
// The bounding box is computed relative to the polygon's reference point, so it needs to be translated to
// model coordinates in order to indicate its model-coordinate extent.
Box boundingBox = Box.computeBoundingBox(Arrays.asList(boundary.vertices));
return boundingBox != null ? boundingBox.translate(refPoint) : null;
}
public Sector getSector()
{
if (this.sector == null && this.isOuterBoundaryValid())
this.sector = Sector.boundingSector(this.getOuterBoundary());
return this.sector;
}
protected boolean mustApplyTexture(DrawContext dc)
{
return this.getTexture() != null && this.textureCoordsBuffer != null;
}
protected boolean shouldUseVBOs(DrawContext dc)
{
return this.numPositions > VBO_THRESHOLD && super.shouldUseVBOs(dc);
}
protected boolean mustRegenerateGeometry(DrawContext dc)
{
if (this.getCurrent().coordBuffer == null)
return true;
if (dc.getVerticalExaggeration() != this.getCurrent().getVerticalExaggeration())
return true;
if (this.mustApplyLighting(dc, null) && this.getCurrent().normalBuffer == null)
return true;
if (this.getAltitudeMode() == WorldWind.ABSOLUTE
&& this.getCurrent().getGlobeStateKey() != null
&& this.getCurrent().getGlobeStateKey().equals(dc.getGlobe().getGlobeStateKey(dc)))
return false;
return super.mustRegenerateGeometry(dc);
}
public void render(DrawContext dc)
{
if (!this.isOuterBoundaryValid())
return;
super.render(dc);
}
protected boolean doMakeOrderedRenderable(DrawContext dc)
{
if (dc.getSurfaceGeometry() == null || !this.isOuterBoundaryValid())
return false;
this.getCurrent().setRotationMatrix(this.getRotation() != null ?
this.computeRotationMatrix(dc.getGlobe()) : null);
this.createMinimalGeometry(dc, this.getCurrent());
// If the shape is less that a pixel in size, don't render it.
if (this.getCurrent().getExtent() == null || dc.isSmall(this.getExtent(), 1))
return false;
if (!this.intersectsFrustum(dc))
return false;
this.createFullGeometry(dc, dc.getTerrain(), this.getCurrent(), true);
return true;
}
protected boolean isOrderedRenderableValid(DrawContext dc)
{
return this.getCurrent().coordBuffer != null && this.isOuterBoundaryValid();
}
protected OGLStackHandler beginDrawing(DrawContext dc, int attrMask)
{
OGLStackHandler ogsh = super.beginDrawing(dc, attrMask);
if (!dc.isPickingMode())
{
// Push an identity texture matrix. This prevents drawSides() from leaking GL texture matrix state. The
// texture matrix stack is popped from OGLStackHandler.pop(), in the finally block below.
GL2 gl = dc.getGL().getGL2(); // GL initialization checks for GL2 compatibility.
ogsh.pushTextureIdentity(gl);
}
return ogsh;
}
protected void doDrawOutline(DrawContext dc)
{
if (this.shouldUseVBOs(dc))
{
int[] vboIds = this.getVboIds(dc);
if (vboIds != null)
this.doDrawOutlineVBO(dc, vboIds, this.getCurrent());
else
this.doDrawOutlineVA(dc, this.getCurrent());
}
else
{
this.doDrawOutlineVA(dc, this.getCurrent());
}
}
protected void doDrawOutlineVA(DrawContext dc, ShapeData shapeData)
{
GL2 gl = dc.getGL().getGL2(); // GL initialization checks for GL2 compatibility.
gl.glVertexPointer(3, GL.GL_FLOAT, 0, shapeData.coordBuffer.rewind());
if (!dc.isPickingMode() && this.mustApplyLighting(dc, null))
gl.glNormalPointer(GL.GL_FLOAT, 0, shapeData.normalBuffer.rewind());
int k = 0;
for (BoundaryInfo boundary : shapeData)
{
gl.glDrawArrays(GL.GL_LINE_STRIP, k, boundary.vertices.length);
k += boundary.vertices.length;
}
// // Diagnostic to show the normal vectors.
// if (this.mustApplyLighting(dc))
// dc.drawNormals(1000, this.boundarySet.coordBuffer, this.boundarySet.normalBuffer);
}
protected void doDrawOutlineVBO(DrawContext dc, int[] vboIds, ShapeData shapeData)
{
GL2 gl = dc.getGL().getGL2(); // GL initialization checks for GL2 compatibility.
gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vboIds[0]);
gl.glVertexPointer(3, GL.GL_FLOAT, 0, 0);
if (!dc.isPickingMode() && this.mustApplyLighting(dc, null))
gl.glNormalPointer(GL.GL_FLOAT, 0, 4 * shapeData.normalBufferPosition);
int k = 0;
for (BoundaryInfo boundary : shapeData)
{
// TODO: check use glMultiDrawArrays
gl.glDrawArrays(GL.GL_LINE_STRIP, k, boundary.vertices.length);
k += boundary.vertices.length;
}
gl.glBindBuffer(GL.GL_ARRAY_BUFFER, 0);
}
protected void doDrawInterior(DrawContext dc)
{
GL2 gl = dc.getGL().getGL2(); // GL initialization checks for GL2 compatibility.
if (!dc.isPickingMode() && mustApplyTexture(dc) && this.getTexture().bind(dc)) // bind initiates retrieval
{
this.getTexture().applyInternalTransform(dc);
gl.glTexCoordPointer(2, GL.GL_FLOAT, 0, this.textureCoordsBuffer.rewind());
dc.getGL().glEnable(GL.GL_TEXTURE_2D);
gl.glEnableClientState(GL2.GL_TEXTURE_COORD_ARRAY);
}
else
{
dc.getGL().glDisable(GL.GL_TEXTURE_2D);
gl.glDisableClientState(GL2.GL_TEXTURE_COORD_ARRAY);
}
if (this.shouldUseVBOs(dc))
{
int[] vboIds = this.getVboIds(dc);
if (vboIds != null)
this.doDrawInteriorVBO(dc, vboIds, this.getCurrent());
else
this.doDrawInteriorVA(dc, this.getCurrent());
}
else
{
this.doDrawInteriorVA(dc, this.getCurrent());
}
}
protected void doDrawInteriorVA(DrawContext dc, ShapeData shapeData)
{
GL2 gl = dc.getGL().getGL2(); // GL initialization checks for GL2 compatibility.
if (!dc.isPickingMode() && this.mustApplyLighting(dc, null))
gl.glNormalPointer(GL.GL_FLOAT, 0, shapeData.normalBuffer.rewind());
FloatBuffer vb = shapeData.coordBuffer;
gl.glVertexPointer(3, GL.GL_FLOAT, 0, vb.rewind());
IntBuffer ib = shapeData.interiorIndicesBuffer;
gl.glDrawElements(GL.GL_TRIANGLES, ib.limit(), GL.GL_UNSIGNED_INT, ib);
}
protected void doDrawInteriorVBO(DrawContext dc, int[] vboIds, ShapeData shapeData)
{
GL2 gl = dc.getGL().getGL2(); // GL initialization checks for GL2 compatibility.
gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vboIds[0]);
gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, vboIds[1]);
gl.glVertexPointer(3, GL.GL_FLOAT, 0, 0);
if (!dc.isPickingMode() && this.mustApplyLighting(dc, null))
gl.glNormalPointer(GL.GL_FLOAT, 0, 4 * shapeData.normalBufferPosition);
gl.glDrawElements(GL.GL_TRIANGLES, shapeData.interiorIndicesBuffer.limit(), GL.GL_UNSIGNED_INT, 0);
gl.glBindBuffer(GL.GL_ARRAY_BUFFER, 0);
gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, 0);
}
protected Matrix computeRotationMatrix(Globe globe)
{
if (this.getRotation() == null)
return null;
Sector s = this.getSector();
if (s == null)
return null;
// Using the four corners of the sector to compute the rotation axis avoids any problems with dateline
// spanning polygons.
Vec4[] verts = s.computeCornerPoints(globe, 1);
Vec4 center = s.computeCenterPoint(globe, 1);
Matrix m1 = Matrix.fromTranslation(center.multiply3(-1));
Matrix m3 = Matrix.fromTranslation(center);
Vec4 normalVec = verts[2].subtract3(verts[0]).cross3(verts[3].subtract3(verts[1])).normalize3();
Matrix m2 = Matrix.fromAxisAngle(Angle.fromDegrees(this.getRotation()), normalVec);
return m3.multiply(m2).multiply(m1);
}
/**
* Compute enough geometry to determine this polygon's extent, reference point and eye distance.
*
* A {@link gov.nasa.worldwind.render.AbstractShape.AbstractShapeData} must be current when this method is called.
*
* @param dc the current draw context.
* @param shapeData the current shape data for this shape.
*/
protected void createMinimalGeometry(DrawContext dc, ShapeData shapeData)
{
Matrix rotationMatrix = shapeData.getRotationMatrix();
Vec4 refPt = this.computeReferencePoint(dc.getTerrain(), rotationMatrix);
if (refPt == null)
return;
shapeData.setReferencePoint(refPt);
// Need only the outer-boundary vertices.
this.computeBoundaryVertices(dc.getTerrain(), shapeData.getOuterBoundaryInfo(),
shapeData.getReferencePoint(), rotationMatrix);
if (shapeData.getExtent() == null || this.getAltitudeMode() != WorldWind.ABSOLUTE)
shapeData.setExtent(this.computeExtent(shapeData.getOuterBoundaryInfo(),
shapeData.getReferencePoint()));
shapeData.setEyeDistance(this.computeEyeDistance(dc, shapeData));
shapeData.setGlobeStateKey(dc.getGlobe().getGlobeStateKey(dc));
shapeData.setVerticalExaggeration(dc.getVerticalExaggeration());
}
/**
* Computes the minimum distance between this polygon and the eye point.
*
* A {@link gov.nasa.worldwind.render.AbstractShape.AbstractShapeData} must be current when this method is called.
*
* @param dc the draw context.
* @param shapeData the current shape data for this shape.
*
* @return the minimum distance from the shape to the eye point.
*/
protected double computeEyeDistance(DrawContext dc, ShapeData shapeData)
{
double minDistance = Double.MAX_VALUE;
Vec4 eyePoint = dc.getView().getEyePoint();
for (Vec4 point : shapeData.getOuterBoundaryInfo().vertices)
{
double d = point.add3(shapeData.getReferencePoint()).distanceTo3(eyePoint);
if (d < minDistance)
minDistance = d;
}
return minDistance;
}
protected Vec4 computeReferencePoint(Terrain terrain, Matrix rotationMatrix)
{
Position refPos = this.getReferencePosition();
if (refPos == null)
return null;
Vec4 refPt = terrain.getSurfacePoint(refPos.getLatitude(), refPos.getLongitude(), 0);
if (refPt == null)
return null;
return rotationMatrix != null ? refPt.transformBy4(rotationMatrix) : refPt;
}
/**
* Computes a shape's full geometry.
*
* @param dc the current draw context.
* @param terrain the terrain to use when computing the geometry.
* @param shapeData the current shape data for this shape.
* @param skipOuterBoundary true if outer boundaries vertices do not need to be calculated, otherwise false.
*/
protected void createFullGeometry(DrawContext dc, Terrain terrain, ShapeData shapeData,
boolean skipOuterBoundary)
{
this.createVertices(terrain, shapeData, skipOuterBoundary);
this.createGeometry(dc, shapeData);
if (this.mustApplyLighting(dc, null))
this.createNormals(shapeData);
else
shapeData.normalBuffer = null;
}
/**
* Computes the Cartesian vertices for this shape.
*
* @param terrain the terrain to use if the altitude mode is relative to the terrain.
* @param shapeData the current shape data for this shape.
* @param skipOuterBoundary if true, don't calculate the vertices for the outer boundary. This is used when the
* outer boundary vertices were computed as minimal geometry.
*/
protected void createVertices(Terrain terrain, ShapeData shapeData, boolean skipOuterBoundary)
{
for (BoundaryInfo boundary : shapeData)
{
if (boundary != shapeData.getOuterBoundaryInfo() || !skipOuterBoundary)
this.computeBoundaryVertices(terrain, boundary, shapeData.getReferencePoint(),
shapeData.getRotationMatrix());
}
}
/**
* Compute the vertices associated with a specified boundary.
*
* @param terrain the terrain to use when calculating vertices relative to the ground.
* @param boundary the boundary to compute vertices for.
* @param refPoint the reference point. Vertices are computed relative to this point, which is usually the
* shape's reference point.
* @param rotationMatrix the rotation matrix to apply to the vertices.
*/
protected void computeBoundaryVertices(Terrain terrain, BoundaryInfo boundary, Vec4 refPoint, Matrix rotationMatrix)
{
int n = boundary.positions.size();
Vec4[] boundaryVertices = new Vec4[n];
for (int i = 0; i < n; i++)
{
if (rotationMatrix == null)
boundaryVertices[i] = this.computePoint(terrain, boundary.positions.get(i)).subtract3(refPoint);
else
boundaryVertices[i] = this.computePoint(terrain, boundary.positions.get(i)).transformBy4(
rotationMatrix).subtract3(refPoint);
}
boundary.vertices = boundaryVertices;
}
/**
* Compute the cap geometry.
*
* A {@link gov.nasa.worldwind.render.AbstractShape.AbstractShapeData} must be current when this method is called.
*
* @param dc the current draw context.
* @param shapeData boundary vertices are calculated during {@link #createMinimalGeometry(DrawContext,
* gov.nasa.worldwind.render.Polygon.ShapeData)}).
*/
protected void createGeometry(DrawContext dc, ShapeData shapeData)
{
int size = this.numPositions * (this.mustApplyLighting(dc, null) ? 6 : 3);
if (shapeData.coordBuffer != null && shapeData.coordBuffer.capacity() >= size)
shapeData.coordBuffer.clear();
else
shapeData.coordBuffer = Buffers.newDirectFloatBuffer(size);
// Capture the position position at which normals buffer starts (in case there are normals)
shapeData.normalBufferPosition = this.numPositions * 3;
// Fill the vertex buffer. Simultaneously create individual buffer slices for each boundary.
for (BoundaryInfo boundary : shapeData)
{
boundary.vertexBuffer = WWBufferUtil.copyArrayToBuffer(boundary.vertices, shapeData.coordBuffer.slice());
shapeData.coordBuffer.position(shapeData.coordBuffer.position() + boundary.vertexBuffer.limit());
}
if (shapeData.cb == null && !shapeData.tessellationError)
this.createTessllationGeometry(dc, shapeData);
if (shapeData.refillIndexBuffer)
this.generateInteriorIndices(shapeData);
}
/**
* Create this shape's vertex normals.
*
* @param shapeData the current shape data holding the vertex coordinates and in which the normal vectors are added.
* The normal vectors are appended to the vertex coordinates in the same buffer. The shape data's
* coordinate buffer must have sufficient capacity to hold the vertex normals.
*/
protected void createNormals(ShapeData shapeData)
{
shapeData.coordBuffer.position(shapeData.normalBufferPosition);
shapeData.normalBuffer = shapeData.coordBuffer.slice();
for (BoundaryInfo boundary : shapeData)
{
this.computeBoundaryNormals(boundary, shapeData.normalBuffer);
}
}
/**
* Fill this shape's vertex buffer objects. If the vertex buffer object resource IDs don't yet exist, create them.
*
* @param dc the current draw context.
*/
protected void fillVBO(DrawContext dc)
{
GL gl = dc.getGL();
ShapeData shapeData = this.getCurrent();
int[] vboIds = (int[]) dc.getGpuResourceCache().get(shapeData.getVboCacheKey());
if (vboIds == null)
{
int size = shapeData.coordBuffer.limit() * 4;
size += shapeData.interiorIndicesBuffer.limit() * 4;
vboIds = new int[2];
gl.glGenBuffers(vboIds.length, vboIds, 0);
dc.getGpuResourceCache().put(shapeData.getVboCacheKey(), vboIds, GpuResourceCache.VBO_BUFFERS, size);
shapeData.refillIndexVBO = true;
}
if (shapeData.refillIndexVBO)
{
try
{
IntBuffer ib = shapeData.interiorIndicesBuffer;
gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, vboIds[1]);
gl.glBufferData(GL.GL_ELEMENT_ARRAY_BUFFER, ib.limit() * 4, ib.rewind(), GL.GL_DYNAMIC_DRAW);
shapeData.refillIndexVBO = false;
}
finally
{
gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, 0);
}
}
try
{
FloatBuffer vb = this.getCurrent().coordBuffer;
gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vboIds[0]);
gl.glBufferData(GL.GL_ARRAY_BUFFER, vb.limit() * 4, vb.rewind(), GL.GL_STATIC_DRAW);
}
finally
{
gl.glBindBuffer(GL.GL_ARRAY_BUFFER, 0);
}
}
/**
* Compute normal vectors for a boundary's vertices.
*
* @param boundary the boundary to compute normals for.
* @param nBuf the buffer in which to place the computed normals. Must have enough remaining space to hold the
* normals.
*
* @return the buffer specified as input, with its limit incremented by the number of vertices copied, and its
* position set to 0.
*/
protected FloatBuffer computeBoundaryNormals(BoundaryInfo boundary, FloatBuffer nBuf)
{
int nVerts = boundary.positions.size();
Vec4[] verts = boundary.vertices;
double avgX, avgY, avgZ;
// Compute normal for first point of boundary.
Vec4 va = verts[1].subtract3(verts[0]);
Vec4 vb = verts[nVerts - 2].subtract3(verts[0]); // nverts - 2 because last and first are same
avgX = (va.y * vb.z) - (va.z * vb.y);
avgY = (va.z * vb.x) - (va.x * vb.z);
avgZ = (va.x * vb.y) - (va.y * vb.x);
// Compute normals for interior boundary points.
for (int i = 1; i < nVerts - 1; i++)
{
va = verts[i + 1].subtract3(verts[i]);
vb = verts[i - 1].subtract3(verts[i]);
avgX += (va.y * vb.z) - (va.z * vb.y);
avgY += (va.z * vb.x) - (va.x * vb.z);
avgZ += (va.x * vb.y) - (va.y * vb.x);
}
avgX /= nVerts - 1;
avgY /= nVerts - 1;
avgZ /= nVerts - 1;
double length = Math.sqrt(avgX * avgX + avgY * avgY + avgZ * avgZ);
for (int i = 0; i < nVerts; i++)
{
nBuf.put((float) (avgX / length)).put((float) (avgY / length)).put((float) (avgZ / length));
}
return nBuf;
}
/**
* Tessellates the polygon.
*
* This method catches {@link OutOfMemoryError} exceptions and if the draw context is not null passes the exception
* to the rendering exception listener (see {@link WorldWindow#addRenderingExceptionListener(gov.nasa.worldwind.event.RenderingExceptionListener)}).
*
* @param dc the draw context.
* @param shapeData the current shape data for this shape.
*/
protected void createTessllationGeometry(DrawContext dc, ShapeData shapeData)
{
// Wrap polygon tessellation in a try/catch block. We do this to catch and handle OutOfMemoryErrors caused during
// tessellation of the polygon vertices. If the polygon cannot be tessellated, we replace the polygon's locations
// with an empty list to prevent subsequent tessellation attempts, and to avoid rendering a misleading
// representation by omitting the polygon.
try
{
Vec4 normal = this.computePolygonNormal(dc, shapeData);
// There's a fallback for non-computable normal in computePolygonNormal, but test here in case the fallback
// doesn't work either.
if (normal == null)
{
String message = Logging.getMessage("Geom.ShapeNormalVectorNotComputable", this);
Logging.logger().log(java.util.logging.Level.SEVERE, message);
shapeData.tessellationError = true;
return;
}
this.tessellatePolygon(shapeData, normal.normalize3());
}
catch (OutOfMemoryError e)
{
String message = Logging.getMessage("generic.ExceptionWhileTessellating", this);
Logging.logger().log(java.util.logging.Level.SEVERE, message, e);
shapeData.tessellationError = true;
if (dc != null)
{
//noinspection ThrowableInstanceNeverThrown
dc.addRenderingException(new WWRuntimeException(message, e));
}
}
}
protected Vec4 computePolygonNormal(DrawContext dc, ShapeData shapeData)
{
// The coord buffer might contain space for normals, but use only the vertices to compute the polygon normal.
shapeData.coordBuffer.rewind();
FloatBuffer coordsOnly = shapeData.coordBuffer.slice();
coordsOnly.limit(this.numPositions * 3);
Vec4 normal = WWMath.computeBufferNormal(coordsOnly, 0);
// The normal vector is null if this is a degenerate polygon representing a line or a single point. We fall
// back to using the globe's surface normal at the reference point. This allows the tessellator to process
// the degenerate polygon without generating an exception.
if (normal == null)
normal = dc.getGlobe().computeSurfaceNormalAtLocation(
this.getReferencePosition().getLatitude(), this.getReferencePosition().getLongitude());
return normal;
}
/**
* Tessellates the polygon from its vertices.
*
* @param shapeData the polygon boundaries.
* @param normal a unit normal vector for the plane containing the polygon vertices. Even though the the vertices
* might not be coplanar, only one representative normal is used for tessellation.
*/
protected void tessellatePolygon(ShapeData shapeData, Vec4 normal)
{
GLUTessellatorSupport glts = new GLUTessellatorSupport();
shapeData.cb = new GLUTessellatorSupport.CollectIndexListsCallback();
glts.beginTessellation(shapeData.cb, normal);
try
{
double[] coords = new double[3];
GLU.gluTessBeginPolygon(glts.getGLUtessellator(), null);
int k = 0;
for (BoundaryInfo boundary : shapeData)
{
GLU.gluTessBeginContour(glts.getGLUtessellator());
FloatBuffer vBuf = boundary.vertexBuffer;
for (int i = 0; i < boundary.positions.size(); i++)
{
coords[0] = vBuf.get(i * 3);
coords[1] = vBuf.get(i * 3 + 1);
coords[2] = vBuf.get(i * 3 + 2);
GLU.gluTessVertex(glts.getGLUtessellator(), coords, 0, k++);
}
GLU.gluTessEndContour(glts.getGLUtessellator());
}
GLU.gluTessEndPolygon(glts.getGLUtessellator());
}
finally
{
// Free any heap memory used for tessellation immediately. If tessellation has consumed all available
// heap memory, we must free memory used by tessellation immediately or subsequent operations such as
// message logging will fail.
glts.endTessellation();
}
}
protected void generateInteriorIndices(ShapeData shapeData)
{
GLUTessellatorSupport.CollectIndexListsCallback cb = shapeData.cb;
int size = this.countTriangleVertices(cb.getPrims(), cb.getPrimTypes());
if (shapeData.interiorIndicesBuffer == null || shapeData.interiorIndicesBuffer.capacity() < size)
shapeData.interiorIndicesBuffer = Buffers.newDirectIntBuffer(size);
else
shapeData.interiorIndicesBuffer.clear();
for (int i = 0; i < cb.getPrims().size(); i++)
{
switch (cb.getPrimTypes().get(i))
{
case GL.GL_TRIANGLES:
Triangle.expandTriangles(cb.getPrims().get(i), shapeData.interiorIndicesBuffer);
break;
case GL.GL_TRIANGLE_FAN:
Triangle.expandTriangleFan(cb.getPrims().get(i), shapeData.interiorIndicesBuffer);
break;
case GL.GL_TRIANGLE_STRIP:
Triangle.expandTriangleStrip(cb.getPrims().get(i), shapeData.interiorIndicesBuffer);
break;
}
}
shapeData.interiorIndicesBuffer.flip();
shapeData.refillIndexBuffer = false;
shapeData.refillIndexVBO = true;
}
protected boolean isSameAsPreviousTerrain(Terrain terrain)
{
if (terrain == null || this.previousIntersectionTerrain == null || terrain != this.previousIntersectionTerrain)
return false;
if (terrain.getVerticalExaggeration() != this.previousIntersectionTerrain.getVerticalExaggeration())
return false;
return this.previousIntersectionGlobeStateKey != null &&
terrain.getGlobe().getGlobeStateKey().equals(this.previousIntersectionGlobeStateKey);
}
public void clearIntersectionGeometry()
{
this.previousIntersectionGlobeStateKey = null;
this.previousIntersectionShapeData = null;
this.previousIntersectionTerrain = null;
}
/**
* Compute the intersections of a specified line with this polygon. If the polygon's altitude mode is other than
* {@link WorldWind#ABSOLUTE}, the polygon's geometry is created relative to the specified terrain rather than the
* terrain used during rendering, which may be at lower level of detail than required for accurate intersection
* determination.
*
* @param line the line to intersect.
* @param terrain the {@link Terrain} to use when computing the polygon's geometry.
*
* @return a list of intersections identifying where the line intersects the polygon, or null if the line does not
* intersect the polygon.
*
* @throws InterruptedException if the operation is interrupted.
* @see Terrain
*/
public List intersect(Line line, Terrain terrain) throws InterruptedException
{
Position refPos = this.getReferencePosition();
if (refPos == null)
return null;
if (!this.isOuterBoundaryValid())
return null;
// Reuse the previously computed high-res shape data if the terrain is the same.
ShapeData highResShapeData = this.isSameAsPreviousTerrain(terrain) ? this.previousIntersectionShapeData
: null;
if (highResShapeData == null)
{
highResShapeData = this.createIntersectionGeometry(terrain);
if (highResShapeData == null)
return null;
this.previousIntersectionShapeData = highResShapeData;
this.previousIntersectionTerrain = terrain;
this.previousIntersectionGlobeStateKey = terrain.getGlobe().getGlobeStateKey();
}
if (highResShapeData.getExtent() != null && highResShapeData.getExtent().intersect(line) == null)
return null;
final Line localLine = new Line(line.getOrigin().subtract3(highResShapeData.getReferencePoint()),
line.getDirection());
List intersections = new ArrayList();
this.intersect(localLine, highResShapeData, intersections);
if (intersections.size() == 0)
return null;
for (Intersection intersection : intersections)
{
Vec4 pt = intersection.getIntersectionPoint().add3(highResShapeData.getReferencePoint());
intersection.setIntersectionPoint(pt);
// Compute intersection position relative to ground.
Position pos = terrain.getGlobe().computePositionFromPoint(pt);
Vec4 gp = terrain.getSurfacePoint(pos.getLatitude(), pos.getLongitude(), 0);
double dist = Math.sqrt(pt.dotSelf3()) - Math.sqrt(gp.dotSelf3());
intersection.setIntersectionPosition(new Position(pos, dist));
intersection.setObject(this);
}
return intersections;
}
protected ShapeData createIntersectionGeometry(Terrain terrain)
{
ShapeData shapeData = new ShapeData(null, this);
Matrix rotationMatrix = this.getRotation() != null ? this.computeRotationMatrix(terrain.getGlobe()) : null;
shapeData.setReferencePoint(this.computeReferencePoint(terrain, rotationMatrix));
if (shapeData.getReferencePoint() == null)
return null;
// Compute the boundary vertices first.
this.createVertices(terrain, shapeData, false);
this.createGeometry(null, shapeData);
shapeData.setExtent(computeExtent(shapeData.getOuterBoundaryInfo(), shapeData.getReferencePoint()));
return shapeData;
}
protected void intersect(Line line, ShapeData shapeData, List intersections)
throws InterruptedException
{
if (shapeData.cb.getPrims() == null)
return;
IntBuffer ib = shapeData.interiorIndicesBuffer;
ib.rewind();
List ti = Triangle.intersectTriangleTypes(line, shapeData.coordBuffer, ib,
GL.GL_TRIANGLES);
if (ti != null && ti.size() > 0)
intersections.addAll(ti);
}
/**
* {@inheritDoc}
*
* Note that this method overwrites the boundary locations lists, and therefore no longer refer to the originally
* specified boundary lists.
*
* @param position the new position of the shape's reference position.
*/
public void moveTo(Position position)
{
if (position == null)
{
String msg = Logging.getMessage("nullValue.PositionIsNull");
Logging.logger().severe(msg);
throw new IllegalArgumentException(msg);
}
if (!this.isOuterBoundaryValid())
return;
Position oldPosition = this.getReferencePosition();
if (oldPosition == null)
return;
List> newBoundaries = new ArrayList>(this.boundaries.size());
for (List boundary : this.boundaries)
{
if (boundary == null || boundary.size() == 0)
continue;
List newList = Position.computeShiftedPositions(oldPosition, position, boundary);
if (newList != null)
newBoundaries.add(newList);
}
this.boundaries = newBoundaries;
this.setReferencePosition(position);
this.reset();
}
/** {@inheritDoc} */
protected void doExportAsKML(XMLStreamWriter xmlWriter) throws IOException, XMLStreamException
{
// Write geometry
xmlWriter.writeStartElement("Polygon");
xmlWriter.writeStartElement("extrude");
xmlWriter.writeCharacters("0");
xmlWriter.writeEndElement();
final String altitudeMode = KMLExportUtil.kmlAltitudeMode(getAltitudeMode());
xmlWriter.writeStartElement("altitudeMode");
xmlWriter.writeCharacters(altitudeMode);
xmlWriter.writeEndElement();
this.writeKMLBoundaries(xmlWriter);
xmlWriter.writeEndElement(); // Polygon
}
/**
* Write the boundary of the polygon as KML.
*
* @param xmlWriter XML writer to receive the output.
*
* @throws IOException If an exception occurs writing the XML stream.
* @throws XMLStreamException If an exception occurs writing the XML stream.
*/
protected void writeKMLBoundaries(XMLStreamWriter xmlWriter) throws IOException, XMLStreamException
{
// Outer boundary
Iterable outerBoundary = this.getOuterBoundary();
if (outerBoundary != null)
{
xmlWriter.writeStartElement("outerBoundaryIs");
exportBoundaryAsLinearRing(xmlWriter, outerBoundary);
xmlWriter.writeEndElement(); // outerBoundaryIs
}
// Inner boundaries. Skip outer boundary, we already dealt with it above
for (int i = 1; i < this.boundaries.size(); i++)
{
xmlWriter.writeStartElement("innerBoundaryIs");
exportBoundaryAsLinearRing(xmlWriter, this.boundaries.get(i));
xmlWriter.writeEndElement(); // innerBoundaryIs
}
}
/**
* Writes the boundary in KML as either a list of lat, lon, altitude tuples or lat, lon tuples, depending on the
* type originally specified.
*
* @param xmlWriter the XML writer.
* @param boundary the boundary to write.
*
* @throws XMLStreamException if an error occurs during writing.
*/
protected void exportBoundaryAsLinearRing(XMLStreamWriter xmlWriter, Iterable boundary)
throws XMLStreamException
{
xmlWriter.writeStartElement("LinearRing");
xmlWriter.writeStartElement("coordinates");
for (LatLon location : boundary)
{
if (location instanceof Position)
{
xmlWriter.writeCharacters(String.format(Locale.US, "%f,%f,%f ",
location.getLongitude().getDegrees(),
location.getLatitude().getDegrees(),
((Position) location).getAltitude()));
}
else
{
xmlWriter.writeCharacters(String.format(Locale.US, "%f,%f ",
location.getLongitude().getDegrees(),
location.getLatitude().getDegrees()));
}
}
xmlWriter.writeEndElement(); // coordinates
xmlWriter.writeEndElement(); // LinearRing
}
}