diff options
Diffstat (limited to 'engine/src/core/com/jme3/scene/shape/Surface.java')
| -rw-r--r-- | engine/src/core/com/jme3/scene/shape/Surface.java | 283 |
1 files changed, 283 insertions, 0 deletions
diff --git a/engine/src/core/com/jme3/scene/shape/Surface.java b/engine/src/core/com/jme3/scene/shape/Surface.java new file mode 100644 index 0000000..77d259b --- /dev/null +++ b/engine/src/core/com/jme3/scene/shape/Surface.java @@ -0,0 +1,283 @@ +package com.jme3.scene.shape;
+
+import com.jme3.math.CurveAndSurfaceMath;
+import com.jme3.math.FastMath;
+import com.jme3.math.Spline.SplineType;
+import com.jme3.math.Vector3f;
+import com.jme3.math.Vector4f;
+import com.jme3.scene.Mesh;
+import com.jme3.scene.VertexBuffer;
+import com.jme3.util.BufferUtils;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * This class represents a surface described by knots, weights and control points.
+ * Currently the following types are supported:
+ * a) NURBS
+ * @author Marcin Roguski (Kealthas)
+ */
+public class Surface extends Mesh {
+
+ private SplineType type; //the type of the surface
+ private List<List<Vector4f>> controlPoints; //space control points and their weights
+ private List<Float>[] knots; //knots of the surface
+ private int basisUFunctionDegree; //the degree of basis U function
+ private int basisVFunctionDegree; //the degree of basis V function
+ private int uSegments; //the amount of U segments
+ private int vSegments; //the amount of V segments
+
+ /**
+ * Constructor. Constructs required surface.
+ * @param controlPoints space control points
+ * @param nurbKnots knots of the surface
+ * @param uSegments the amount of U segments
+ * @param vSegments the amount of V segments
+ * @param basisUFunctionDegree the degree of basis U function
+ * @param basisVFunctionDegree the degree of basis V function
+ */
+ private Surface(List<List<Vector4f>> controlPoints, List<Float>[] nurbKnots,
+ int uSegments, int vSegments, int basisUFunctionDegree, int basisVFunctionDegree) {
+ this.validateInputData(controlPoints, nurbKnots, uSegments, vSegments);
+ this.type = SplineType.Nurb;
+ this.uSegments = uSegments;
+ this.vSegments = vSegments;
+ this.controlPoints = controlPoints;
+ this.knots = nurbKnots;
+ this.basisUFunctionDegree = basisUFunctionDegree;
+ CurveAndSurfaceMath.prepareNurbsKnots(nurbKnots[0], basisUFunctionDegree);
+ if (nurbKnots[1] != null) {
+ this.basisVFunctionDegree = basisVFunctionDegree;
+ CurveAndSurfaceMath.prepareNurbsKnots(nurbKnots[1], basisVFunctionDegree);
+ }
+
+ this.buildSurface();
+ }
+
+ /**
+ * This method creates a NURBS surface.
+ * @param controlPoints space control points
+ * @param nurbKnots knots of the surface
+ * @param uSegments the amount of U segments
+ * @param vSegments the amount of V segments
+ * @param basisUFunctionDegree the degree of basis U function
+ * @param basisVFunctionDegree the degree of basis V function
+ * @return an instance of NURBS surface
+ */
+ public static final Surface createNurbsSurface(List<List<Vector4f>> controlPoints, List<Float>[] nurbKnots,
+ int uSegments, int vSegments, int basisUFunctionDegree, int basisVFunctionDegree) {
+ Surface result = new Surface(controlPoints, nurbKnots, uSegments, vSegments, basisUFunctionDegree, basisVFunctionDegree);
+ result.type = SplineType.Nurb;
+ return result;
+ }
+
+ /**
+ * This method creates the surface.
+ */
+ private void buildSurface() {
+ boolean smooth = true;//TODO: take smoothing into consideration
+ float minUKnot = this.getMinUNurbKnot();
+ float maxUKnot = this.getMaxUNurbKnot();
+ float deltaU = (maxUKnot - minUKnot) / uSegments;
+
+ float minVKnot = this.getMinVNurbKnot();
+ float maxVKnot = this.getMaxVNurbKnot();
+ float deltaV = (maxVKnot - minVKnot) / vSegments;
+
+ Vector3f[] vertices = new Vector3f[(uSegments + 1) * (vSegments + 1)];
+
+ float u = minUKnot, v = minVKnot;
+ int arrayIndex = 0;
+
+ for (int i = 0; i <= vSegments; ++i) {
+ for (int j = 0; j <= uSegments; ++j) {
+ Vector3f interpolationResult = new Vector3f();
+ CurveAndSurfaceMath.interpolate(u, v, controlPoints, knots, basisUFunctionDegree, basisVFunctionDegree, interpolationResult);
+ vertices[arrayIndex++] = interpolationResult;
+ u += deltaU;
+ }
+ u = minUKnot;
+ v += deltaV;
+ }
+
+ //adding indexes
+ int uVerticesAmount = uSegments + 1;
+ int[] indices = new int[uSegments * vSegments * 6];
+ arrayIndex = 0;
+ for (int i = 0; i < vSegments; ++i) {
+ for (int j = 0; j < uSegments; ++j) {
+ indices[arrayIndex++] = j + i * uVerticesAmount;
+ indices[arrayIndex++] = j + i * uVerticesAmount + 1;
+ indices[arrayIndex++] = j + i * uVerticesAmount + uVerticesAmount;
+ indices[arrayIndex++] = j + i * uVerticesAmount + 1;
+ indices[arrayIndex++] = j + i * uVerticesAmount + uVerticesAmount + 1;
+ indices[arrayIndex++] = j + i * uVerticesAmount + uVerticesAmount;
+ }
+ }
+
+ //normalMap merges normals of faces that will be rendered smooth
+ Map<Vector3f, Vector3f> normalMap = new HashMap<Vector3f, Vector3f>(vertices.length);
+ for (int i = 0; i < indices.length; i += 3) {
+ Vector3f n = FastMath.computeNormal(vertices[indices[i]], vertices[indices[i + 1]], vertices[indices[i + 2]]);
+ this.addNormal(n, normalMap, smooth, vertices[indices[i]], vertices[indices[i + 1]], vertices[indices[i + 2]]);
+ }
+ //preparing normal list (the order of normals must match the order of vertices)
+ float[] normals = new float[vertices.length * 3];
+ arrayIndex = 0;
+ for (int i = 0; i < vertices.length; ++i) {
+ Vector3f n = normalMap.get(vertices[i]);
+ normals[arrayIndex++] = n.x;
+ normals[arrayIndex++] = n.y;
+ normals[arrayIndex++] = n.z;
+ }
+
+ this.setBuffer(VertexBuffer.Type.Position, 3, BufferUtils.createFloatBuffer(vertices));
+ this.setBuffer(VertexBuffer.Type.Index, 3, indices);
+ this.setBuffer(VertexBuffer.Type.Normal, 3, normals);
+ this.updateBound();
+ this.updateCounts();
+ }
+
+ public List<List<Vector4f>> getControlPoints() {
+ return controlPoints;
+ }
+
+ /**
+ * This method returns the amount of U control points.
+ * @return the amount of U control points
+ */
+ public int getUControlPointsAmount() {
+ return controlPoints.size();
+ }
+
+ /**
+ * This method returns the amount of V control points.
+ * @return the amount of V control points
+ */
+ public int getVControlPointsAmount() {
+ return controlPoints.get(0) == null ? 0 : controlPoints.get(0).size();
+ }
+
+ /**
+ * This method returns the degree of basis U function.
+ * @return the degree of basis U function
+ */
+ public int getBasisUFunctionDegree() {
+ return basisUFunctionDegree;
+ }
+
+ /**
+ * This method returns the degree of basis V function.
+ * @return the degree of basis V function
+ */
+ public int getBasisVFunctionDegree() {
+ return basisVFunctionDegree;
+ }
+
+ /**
+ * This method returns the knots for specified dimension (U knots - value: '0',
+ * V knots - value: '1').
+ * @param dim an integer specifying if the U or V knots are required
+ * @return an array of knots
+ */
+ public List<Float> getKnots(int dim) {
+ return knots[dim];
+ }
+
+ /**
+ * This method returns the type of the surface.
+ * @return the type of the surface
+ */
+ public SplineType getType() {
+ return type;
+ }
+
+ /**
+ * This method returns the minimum nurb curve U knot value.
+ * @return the minimum nurb curve knot value
+ */
+ private float getMinUNurbKnot() {
+ return knots[0].get(basisUFunctionDegree - 1);
+ }
+
+ /**
+ * This method returns the maximum nurb curve U knot value.
+ * @return the maximum nurb curve knot value
+ */
+ private float getMaxUNurbKnot() {
+ return knots[0].get(knots[0].size() - basisUFunctionDegree);
+ }
+
+ /**
+ * This method returns the minimum nurb curve U knot value.
+ * @return the minimum nurb curve knot value
+ */
+ private float getMinVNurbKnot() {
+ return knots[1].get(basisVFunctionDegree - 1);
+ }
+
+ /**
+ * This method returns the maximum nurb curve U knot value.
+ * @return the maximum nurb curve knot value
+ */
+ private float getMaxVNurbKnot() {
+ return knots[1].get(knots[1].size() - basisVFunctionDegree);
+ }
+
+ /**
+ * This method adds a normal to a normals' map. This map is used to merge normals of a vertor that should be rendered smooth.
+ * @param normalToAdd
+ * a normal to be added
+ * @param normalMap
+ * merges normals of faces that will be rendered smooth; the key is the vertex and the value - its normal vector
+ * @param smooth
+ * the variable that indicates wheather to merge normals (creating the smooth mesh) or not
+ * @param vertices
+ * a list of vertices read from the blender file
+ */
+ private void addNormal(Vector3f normalToAdd, Map<Vector3f, Vector3f> normalMap, boolean smooth, Vector3f... vertices) {
+ for (Vector3f v : vertices) {
+ Vector3f n = normalMap.get(v);
+ if (!smooth || n == null) {
+ normalMap.put(v, normalToAdd.clone());
+ } else {
+ n.addLocal(normalToAdd).normalizeLocal();
+ }
+ }
+ }
+
+ /**
+ * This method validates the input data. It throws {@link IllegalArgumentException} if
+ * the data is invalid.
+ * @param controlPoints space control points
+ * @param nurbKnots knots of the surface
+ * @param uSegments the amount of U segments
+ * @param vSegments the amount of V segments
+ */
+ private void validateInputData(List<List<Vector4f>> controlPoints, List<Float>[] nurbKnots,
+ int uSegments, int vSegments) {
+ int uPointsAmount = controlPoints.get(0).size();
+ for (int i = 1; i < controlPoints.size(); ++i) {
+ if (controlPoints.get(i).size() != uPointsAmount) {
+ throw new IllegalArgumentException("The amount of 'U' control points is invalid!");
+ }
+ }
+ if (uSegments <= 0) {
+ throw new IllegalArgumentException("U segments amount should be positive!");
+ }
+ if (vSegments < 0) {
+ throw new IllegalArgumentException("V segments amount cannot be negative!");
+ }
+ if (nurbKnots.length != 2) {
+ throw new IllegalArgumentException("Nurb surface should have two rows of knots!");
+ }
+ for (int i = 0; i < nurbKnots.length; ++i) {
+ for (int j = 0; j < nurbKnots[i].size() - 1; ++j) {
+ if (nurbKnots[i].get(j) > nurbKnots[i].get(j + 1)) {
+ throw new IllegalArgumentException("The knots' values cannot decrease!");
+ }
+ }
+ }
+ }
+}
|