--- /dev/null
+// FIXME
+// Copyright 2002 Adam Megacz, see the COPYING file for licensing [GPL]
+package org.ibex;
+import java.util.*;
+
+// FIXME: offer a "subpixel" mode where we pass floats to the Platform and don't do any snapping
+// FIXME: fracture when realizing instead of when parsing?
+
+/*
+ v1.0
+ - textpath
+ - gradients
+ - patterns
+ - clipping/masking
+ - filters (filtering of a group must be performed AFTER the group is assembled; sep. canvas)
+
+ v1.1
+ - bump caps [requires Paint that can fill circles...] [remember to distinguish between closed/unclosed]
+ - line joins
+ - mitre (hard)
+ - bevel (easy)
+ - bump (easy, but requires 'round' Paint)
+ - subtree sharing? otherwise the memory consumption might be outrageous... clone="" attribute?
+ - better clipping
+ - intersect clip regions (linearity)
+ - clip on trapezoids, not pixels
+ - faster gradients and patterns:
+ - transform each corner of the trapezoid and then interpolate
+*/
+
+/** Ibex's fully conformant Static SVG Viewer; see SVG spec, section G.7 */
+public final class VectorGraphics {
+
+ // Private Constants ///////////////////////////////////////////////////////////////////
+
+ private static final int DEFAULT_PATHLEN = 1000;
+ private static final float PI = (float)Math.PI;
+
+
+ // Public entry points /////////////////////////////////////////////////////////////////
+
+ public static VectorPath parseVectorPath(String s) {
+ if (s == null) return null;
+ PathTokenizer t = new PathTokenizer(s);
+ VectorPath ret = new VectorPath();
+ char last_command = 'M';
+ boolean first = true;
+ while(t.hasMoreTokens()) {
+ char command = t.parseCommand();
+ if (first && command != 'M') throw new RuntimeException("the first command of a path must be 'M'");
+ first = false;
+ boolean relative = Character.toLowerCase(command) == command;
+ command = Character.toLowerCase(command);
+ ret.parseSingleCommandAndArguments(t, command, relative);
+ last_command = command;
+ }
+ return ret;
+ }
+
+
+ // Affine //////////////////////////////////////////////////////////////////////////////
+
+ /** an affine transform; all operations are destructive */
+ public static final class Affine {
+
+ // [ a b e ]
+ // [ c d f ]
+ // [ 0 0 1 ]
+ public float a, b, c, d, e, f;
+
+ Affine(float _a, float _b, float _c, float _d, float _e, float _f) { a = _a; b = _b; c = _c; d = _d; e = _e; f = _f; }
+ public String toString() { return "[ " + a + ", " + b + ", " + c + ", " + d + ", " + e + ", " + f + " ]"; }
+ public Affine copy() { return new Affine(a, b, c, d, e, f); }
+ public static Affine identity() { return new Affine(1, 0, 0, 1, 0, 0); }
+ public static Affine scale(float sx, float sy) { return new Affine(sx, 0, 0, sy, 0, 0); }
+ public static Affine shear(float degrees) {
+ return new Affine(1, 0, (float)Math.tan(degrees * (float)(Math.PI / 180.0)), 1, 0, 0); }
+ public static Affine translate(float tx, float ty) { return new Affine(1, 0, 0, 1, tx, ty); }
+ public static Affine flip(boolean horiz, boolean vert) { return new Affine(horiz ? -1 : 1, 0, 0, vert ? -1 : 1, 0, 0); }
+ public float multiply_px(float x, float y) { return x * a + y * c + e; }
+ public float multiply_py(float x, float y) { return x * b + y * d + f; }
+ public boolean equalsIgnoringTranslation(Affine x) { return a == x.a && b == x.b && c == x.c && d == x.d; }
+
+ public boolean equals(Object o) {
+ if (!(o instanceof Affine)) return false;
+ Affine x = (Affine)o;
+ return a == x.a && b == x.b && c == x.c && d == x.d && e == x.e && f == x.f;
+ }
+
+ public static Affine rotate(float degrees) {
+ float s = (float)Math.sin(degrees * (float)(Math.PI / 180.0));
+ float c = (float)Math.cos(degrees * (float)(Math.PI / 180.0));
+ return new Affine(c, s, -s, c, 0, 0);
+ }
+
+ /** this = this * a */
+ public Affine multiply(Affine A) {
+ float _a = this.a * A.a + this.b * A.c;
+ float _b = this.a * A.b + this.b * A.d;
+ float _c = this.c * A.a + this.d * A.c;
+ float _d = this.c * A.b + this.d * A.d;
+ float _e = this.e * A.a + this.f * A.c + A.e;
+ float _f = this.e * A.b + this.f * A.d + A.f;
+ a = _a; b = _b; c = _c; d = _d; e = _e; f = _f;
+ return this;
+ }
+
+ public void invert() {
+ float det = 1 / (a * d - b * c);
+ float _a = d * det;
+ float _b = -1 * b * det;
+ float _c = -1 * c * det;
+ float _d = a * det;
+ float _e = -1 * e * a - f * c;
+ float _f = -1 * e * b - f * d;
+ a = _a; b = _b; c = _c; d = _d; e = _e; f = _f;
+ }
+ }
+
+
+ // PathTokenizer //////////////////////////////////////////////////////////////////////////////
+
+ public static Affine parseTransform(String t) {
+ if (t == null) return null;
+ t = t.trim();
+ Affine ret = VectorGraphics.Affine.identity();
+ while (t.length() > 0) {
+ if (t.startsWith("skewX(")) {
+ // FIXME
+
+ } else if (t.startsWith("shear(")) {
+ // FIXME: nonstandard; remove this
+ ret.multiply(VectorGraphics.Affine.shear(Float.parseFloat(t.substring(t.indexOf('(') + 1, t.indexOf(')')))));
+
+ } else if (t.startsWith("skewY(")) {
+ // FIXME
+
+ } else if (t.startsWith("rotate(")) {
+ String sub = t.substring(t.indexOf('(') + 1, t.indexOf(')'));
+ if (sub.indexOf(',') != -1) {
+ float angle = Float.parseFloat(sub.substring(0, sub.indexOf(',')));
+ sub = sub.substring(sub.indexOf(',') + 1);
+ float cx = Float.parseFloat(sub.substring(0, sub.indexOf(',')));
+ sub = sub.substring(sub.indexOf(',') + 1);
+ float cy = Float.parseFloat(sub);
+ ret.multiply(VectorGraphics.Affine.translate(cx, cy));
+ ret.multiply(VectorGraphics.Affine.rotate(angle));
+ ret.multiply(VectorGraphics.Affine.translate(-1 * cx, -1 * cy));
+ } else {
+ ret.multiply(VectorGraphics.Affine.rotate(Float.parseFloat(t.substring(t.indexOf('(') + 1, t.indexOf(')')))));
+ }
+
+ } else if (t.startsWith("translate(")) {
+ String sub = t.substring(t.indexOf('(') + 1, t.indexOf(')'));
+ if (sub.indexOf(',') > -1) {
+ ret.multiply(VectorGraphics.Affine.translate(Float.parseFloat(t.substring(t.indexOf('(') + 1, t.indexOf(','))),
+ Float.parseFloat(t.substring(t.indexOf(',') + 1, t.indexOf(')')))));
+ } else {
+ ret.multiply(VectorGraphics.Affine.translate(Float.parseFloat(t.substring(t.indexOf('(') + 1, t.indexOf(','))), 0));
+ }
+
+ } else if (t.startsWith("flip(")) {
+ String which = t.substring(t.indexOf('(') + 1, t.indexOf(')'));
+ ret.multiply(VectorGraphics.Affine.flip(which.equals("horizontal"), which.equals("vertical")));
+
+ } else if (t.startsWith("scale(")) {
+ String sub = t.substring(t.indexOf('(') + 1, t.indexOf(')'));
+ if (sub.indexOf(',') > -1) {
+ ret.multiply(VectorGraphics.Affine.scale(Float.parseFloat(t.substring(t.indexOf('(') + 1, t.indexOf(','))),
+ Float.parseFloat(t.substring(t.indexOf(',') + 1, t.indexOf(')')))));
+ } else {
+ ret.multiply(VectorGraphics.Affine.scale(Float.parseFloat(t.substring(t.indexOf('(') + 1, t.indexOf(','))),
+ Float.parseFloat(t.substring(t.indexOf('(') + 1, t.indexOf(',')))));
+ }
+
+ } else if (t.startsWith("matrix(")) {
+ // FIXME: is this mapped right?
+ float d[] = new float[6];
+ StringTokenizer st = new StringTokenizer(t, ",", false);
+ for(int i=0; i<6; i++)
+ d[i] = Float.parseFloat(st.nextToken());
+ ret.multiply(new VectorGraphics.Affine(d[0], d[1], d[2], d[3], d[4], d[5]));
+ }
+ t = t.substring(t.indexOf(')') + 1).trim();
+ }
+ return ret;
+ }
+
+ public static final float PX_PER_INCH = 72;
+ public static final float INCHES_PER_CM = (float)0.3937;
+ public static final float INCHES_PER_MM = INCHES_PER_CM / 10;
+
+ public static class PathTokenizer {
+ // FIXME: check array bounds exception for improperly terminated string
+ String s;
+ int i = 0;
+ char lastCommand = 'M';
+ public PathTokenizer(String s) { this.s = s; }
+ private void consumeWhitespace() {
+ while(i < s.length() && (Character.isWhitespace(s.charAt(i)))) i++;
+ if (i < s.length() && s.charAt(i) == ',') i++;
+ while(i < s.length() && (Character.isWhitespace(s.charAt(i)))) i++;
+ }
+ public boolean hasMoreTokens() { consumeWhitespace(); return i < s.length(); }
+ public char parseCommand() {
+ consumeWhitespace();
+ char c = s.charAt(i);
+ if (!Character.isLetter(c)) return lastCommand;
+ i++;
+ return lastCommand = c;
+ }
+ public float parseFloat() {
+ consumeWhitespace();
+ int start = i;
+ float multiplier = 1;
+ for(; i < s.length(); i++) {
+ char c = s.charAt(i);
+ if (Character.isWhitespace(c) || c == ',' || (c == '-' && i != start)) break;
+ if (!((c >= '0' && c <= '9') || c == '.' || c == 'e' || c == 'E' || c == '-')) {
+ if (c == '%') { // FIXME
+ } else if (s.regionMatches(i, "pt", 0, i+2)) { // FIXME
+ } else if (s.regionMatches(i, "em", 0, i+2)) { // FIXME
+ } else if (s.regionMatches(i, "pc", 0, i+2)) { // FIXME
+ } else if (s.regionMatches(i, "ex", 0, i+2)) { // FIXME
+ } else if (s.regionMatches(i, "mm", 0, i+2)) { i += 2; multiplier = INCHES_PER_MM * PX_PER_INCH; break;
+ } else if (s.regionMatches(i, "cm", 0, i+2)) { i += 2; multiplier = INCHES_PER_CM * PX_PER_INCH; break;
+ } else if (s.regionMatches(i, "in", 0, i+2)) { i += 2; multiplier = PX_PER_INCH; break;
+ } else if (s.regionMatches(i, "px", 0, i+2)) { i += 2; break;
+ } else if (Character.isLetter(c)) break;
+ throw new RuntimeException("didn't expect character \"" + c + "\" in a numeric constant");
+ }
+ }
+ if (start == i) throw new RuntimeException("FIXME");
+ return Float.parseFloat(s.substring(start, i)) * multiplier;
+ }
+ }
+
+
+ // Abstract Path //////////////////////////////////////////////////////////////////////////////
+
+ /** an abstract path; may contain splines and arcs */
+ public static class VectorPath {
+
+ // the number of vertices on this path
+ int numvertices = 0;
+
+ // the vertices of the path
+ float[] x = new float[DEFAULT_PATHLEN];
+ float[] y = new float[DEFAULT_PATHLEN];
+
+ // the type of each edge; type[i] is the type of the edge from x[i],y[i] to x[i+1],y[i+1]
+ byte[] type = new byte[DEFAULT_PATHLEN];
+
+ // bezier control points
+ float[] c1x = new float[DEFAULT_PATHLEN]; // or rx (arcto)
+ float[] c1y = new float[DEFAULT_PATHLEN]; // or ry (arcto)
+ float[] c2x = new float[DEFAULT_PATHLEN]; // or x-axis-rotation (arcto)
+ float[] c2y = new float[DEFAULT_PATHLEN]; // or large-arc << 1 | sweep (arcto)
+
+ boolean closed = false;
+
+ static final byte TYPE_MOVETO = 0;
+ static final byte TYPE_LINETO = 1;
+ static final byte TYPE_ARCTO = 2;
+ static final byte TYPE_CUBIC = 3;
+ static final byte TYPE_QUADRADIC = 4;
+
+ /** Creates a concrete vector path transformed through the given matrix. */
+ public RasterPath realize(Affine a) {
+
+ RasterPath ret = new RasterPath();
+ int NUMSTEPS = 5; // FIXME
+ ret.numvertices = 1;
+ ret.x[0] = (int)Math.round(a.multiply_px(x[0], y[0]));
+ ret.y[0] = (int)Math.round(a.multiply_py(x[0], y[0]));
+
+ for(int i=1; i<numvertices; i++) {
+ if (type[i] == TYPE_LINETO) {
+ float rx = x[i];
+ float ry = y[i];
+ ret.x[ret.numvertices] = (int)Math.round(a.multiply_px(rx, ry));
+ ret.y[ret.numvertices] = (int)Math.round(a.multiply_py(rx, ry));
+ ret.edges[ret.numedges++] = ret.numvertices - 1; ret.numvertices++;
+
+ } else if (type[i] == TYPE_MOVETO) {
+ float rx = x[i];
+ float ry = y[i];
+ ret.x[ret.numvertices] = (int)Math.round(a.multiply_px(rx, ry));
+ ret.y[ret.numvertices] = (int)Math.round(a.multiply_py(rx, ry));
+ ret.numvertices++;
+
+ } else if (type[i] == TYPE_ARCTO) {
+ float rx = c1x[i];
+ float ry = c1y[i];
+ float phi = c2x[i];
+ float fa = ((int)c2y[i]) >> 1;
+ float fs = ((int)c2y[i]) & 1;
+ float x1 = x[i];
+ float y1 = y[i];
+ float x2 = x[i+1];
+ float y2 = y[i+1];
+
+ // F.6.5: given x1,y1,x2,y2,fa,fs, compute cx,cy,theta1,dtheta
+ float x1_ = (float)Math.cos(phi) * (x1 - x2) / 2 + (float)Math.sin(phi) * (y1 - y2) / 2;
+ float y1_ = -1 * (float)Math.sin(phi) * (x1 - x2) / 2 + (float)Math.cos(phi) * (y1 - y2) / 2;
+ float tmp = (float)Math.sqrt((rx * rx * ry * ry - rx * rx * y1_ * y1_ - ry * ry * x1_ * x1_) /
+ (rx * rx * y1_ * y1_ + ry * ry * x1_ * x1_));
+ float cx_ = (fa == fs ? -1 : 1) * tmp * (rx * y1_ / ry);
+ float cy_ = (fa == fs ? -1 : 1) * -1 * tmp * (ry * x1_ / rx);
+ float cx = (float)Math.cos(phi) * cx_ - (float)Math.sin(phi) * cy_ + (x1 + x2) / 2;
+ float cy = (float)Math.sin(phi) * cx_ + (float)Math.cos(phi) * cy_ + (y1 + y2) / 2;
+
+ // F.6.4 Conversion from center to endpoint parameterization
+ float ux = 1, uy = 0, vx = (x1_ - cx_) / rx, vy = (y1_ - cy_) / ry;
+ float det = ux * vy - uy * vx;
+ float theta1 = (det < 0 ? -1 : 1) *
+ (float)Math.acos((ux * vx + uy * vy) /
+ ((float)Math.sqrt(ux * ux + uy * uy) * (float)Math.sqrt(vx * vx + vy * vy)));
+ ux = (x1_ - cx_) / rx; uy = (y1_ - cy_) / ry;
+ vx = (-1 * x1_ - cx_) / rx; vy = (-1 * y1_ - cy_) / ry;
+ det = ux * vy - uy * vx;
+ float dtheta = (det < 0 ? -1 : 1) *
+ (float)Math.acos((ux * vx + uy * vy) /
+ ((float)Math.sqrt(ux * ux + uy * uy) * (float)Math.sqrt(vx * vx + vy * vy)));
+ dtheta = dtheta % (float)(2 * Math.PI);
+
+ if (fs == 0 && dtheta > 0) theta1 -= 2 * PI;
+ if (fs == 1 && dtheta < 0) theta1 += 2 * PI;
+
+ if (fa == 1 && dtheta < 0) dtheta = 2 * PI + dtheta;
+ else if (fa == 1 && dtheta > 0) dtheta = -1 * (2 * PI - dtheta);
+
+ // FIXME: integrate F.6.6
+ // FIXME: isn't quite ending where it should...
+
+ // F.6.3: Parameterization alternatives
+ float theta = theta1;
+ for(int j=0; j<NUMSTEPS; j++) {
+ float rasterx = rx * (float)Math.cos(theta) * (float)Math.cos(phi) -
+ ry * (float)Math.sin(theta) * (float)Math.sin(phi) + cx;
+ float rastery = rx * (float)Math.cos(theta) * (float)Math.sin(phi) +
+ ry * (float)Math.cos(phi) * (float)Math.sin(theta) + cy;
+ ret.x[ret.numvertices] = (int)Math.round(a.multiply_px(rasterx, rastery));
+ ret.y[ret.numvertices] = (int)Math.round(a.multiply_py(rasterx, rastery));
+ ret.edges[ret.numedges++] = ret.numvertices - 1; ret.numvertices++;
+ theta += dtheta / NUMSTEPS;
+ }
+
+ } else if (type[i] == TYPE_CUBIC) {
+
+ float ax = x[i+1] - 3 * c2x[i] + 3 * c1x[i] - x[i];
+ float bx = 3 * c2x[i] - 6 * c1x[i] + 3 * x[i];
+ float cx = 3 * c1x[i] - 3 * x[i];
+ float dx = x[i];
+ float ay = y[i+1] - 3 * c2y[i] + 3 * c1y[i] - y[i];
+ float by = 3 * c2y[i] - 6 * c1y[i] + 3 * y[i];
+ float cy = 3 * c1y[i] - 3 * y[i];
+ float dy = y[i];
+
+ for(float t=0; t<1; t += 1 / (float)NUMSTEPS) {
+ float rx = ax * t * t * t + bx * t * t + cx * t + dx;
+ float ry = ay * t * t * t + by * t * t + cy * t + dy;
+ ret.x[ret.numvertices] = (int)Math.round(a.multiply_px(rx, ry));
+ ret.y[ret.numvertices] = (int)Math.round(a.multiply_py(rx, ry));
+ ret.edges[ret.numedges++] = ret.numvertices - 1; ret.numvertices++;
+ }
+
+
+ } else if (type[i] == TYPE_QUADRADIC) {
+
+ float bx = x[i+1] - 2 * c1x[i] + x[i];
+ float cx = 2 * c1x[i] - 2 * x[i];
+ float dx = x[i];
+ float by = y[i+1] - 2 * c1y[i] + y[i];
+ float cy = 2 * c1y[i] - 2 * y[i];
+ float dy = y[i];
+
+ for(float t=0; t<1; t += 1 / (float)NUMSTEPS) {
+ float rx = bx * t * t + cx * t + dx;
+ float ry = by * t * t + cy * t + dy;
+ ret.x[ret.numvertices] = (int)Math.round(a.multiply_px(rx, ry));
+ ret.y[ret.numvertices] = (int)Math.round(a.multiply_py(rx, ry));
+ ret.edges[ret.numedges++] = ret.numvertices - 1; ret.numvertices++;
+ }
+
+ }
+
+ }
+
+ if (ret.numedges > 0) ret.sort(0, ret.numedges - 1, false);
+ return ret;
+ }
+
+ protected void parseSingleCommandAndArguments(PathTokenizer t, char command, boolean relative) {
+ if (numvertices == 0 && command != 'm') throw new RuntimeException("first command MUST be an 'm'");
+ if (numvertices > x.length - 2) {
+ float[] new_x = new float[x.length * 2]; System.arraycopy(x, 0, new_x, 0, x.length); x = new_x;
+ float[] new_y = new float[y.length * 2]; System.arraycopy(y, 0, new_y, 0, y.length); y = new_y;
+ }
+ switch(command) {
+ case 'z': {
+ int where;
+ type[numvertices-1] = TYPE_LINETO;
+ for(where = numvertices - 1; where > 0; where--)
+ if (type[where - 1] == TYPE_MOVETO) break;
+ x[numvertices] = x[where];
+ y[numvertices] = y[where];
+ numvertices++;
+ closed = true;
+ break;
+ }
+
+ case 'm': {
+ if (numvertices > 0) type[numvertices-1] = TYPE_MOVETO;
+ x[numvertices] = t.parseFloat() + (relative ? x[numvertices - 1] : 0);
+ y[numvertices] = t.parseFloat() + (relative ? y[numvertices - 1] : 0);
+ numvertices++;
+ break;
+ }
+
+ case 'l': case 'h': case 'v': {
+ type[numvertices-1] = TYPE_LINETO;
+ float first = t.parseFloat(), second;
+ if (command == 'h') {
+ second = relative ? 0 : y[numvertices - 1];
+ } else if (command == 'v') {
+ second = first; first = relative ? 0 : x[numvertices - 1];
+ } else {
+ second = t.parseFloat();
+ }
+ x[numvertices] = first + (relative ? x[numvertices - 1] : 0);
+ y[numvertices] = second + (relative ? y[numvertices - 1] : 0);
+ numvertices++;
+ break;
+ }
+
+ case 'a': {
+ type[numvertices-1] = TYPE_ARCTO;
+ c1x[numvertices-1] = t.parseFloat() + (relative ? x[numvertices - 1] : 0);
+ c1y[numvertices-1] = t.parseFloat() + (relative ? y[numvertices - 1] : 0);
+ c2x[numvertices-1] = (t.parseFloat() / 360) * 2 * PI;
+ c2y[numvertices-1] = (((int)t.parseFloat()) << 1) | (int)t.parseFloat();
+ x[numvertices] = t.parseFloat() + (relative ? x[numvertices - 1] : 0);
+ y[numvertices] = t.parseFloat() + (relative ? y[numvertices - 1] : 0);
+ numvertices++;
+ break;
+ }
+
+ case 's': case 'c': {
+ type[numvertices-1] = TYPE_CUBIC;
+ if (command == 'c') {
+ c1x[numvertices-1] = t.parseFloat() + (relative ? x[numvertices - 1] : 0);
+ c1y[numvertices-1] = t.parseFloat() + (relative ? y[numvertices - 1] : 0);
+ } else if (numvertices > 1 && type[numvertices-2] == TYPE_CUBIC) {
+ c1x[numvertices-1] = 2 * x[numvertices - 1] - c2x[numvertices-2];
+ c1y[numvertices-1] = 2 * y[numvertices - 1] - c2y[numvertices-2];
+ } else {
+ c1x[numvertices-1] = x[numvertices-1];
+ c1y[numvertices-1] = y[numvertices-1];
+ }
+ c2x[numvertices-1] = t.parseFloat() + (relative ? x[numvertices - 1] : 0);
+ c2y[numvertices-1] = t.parseFloat() + (relative ? y[numvertices - 1] : 0);
+ x[numvertices] = t.parseFloat() + (relative ? x[numvertices - 1] : 0);
+ y[numvertices] = t.parseFloat() + (relative ? y[numvertices - 1] : 0);
+ numvertices++;
+ break;
+ }
+
+ case 't': case 'q': {
+ type[numvertices-1] = TYPE_QUADRADIC;
+ if (command == 'q') {
+ c1x[numvertices-1] = t.parseFloat() + (relative ? x[numvertices - 1] : 0);
+ c1y[numvertices-1] = t.parseFloat() + (relative ? y[numvertices - 1] : 0);
+ } else if (numvertices > 1 && type[numvertices-2] == TYPE_QUADRADIC) {
+ c1x[numvertices-1] = 2 * x[numvertices - 1] - c1x[numvertices-2];
+ c1y[numvertices-1] = 2 * y[numvertices - 1] - c1y[numvertices-2];
+ } else {
+ c1x[numvertices-1] = x[numvertices-1];
+ c1y[numvertices-1] = y[numvertices-1];
+ }
+ x[numvertices] = t.parseFloat() + (relative ? x[numvertices - 1] : 0);
+ y[numvertices] = t.parseFloat() + (relative ? y[numvertices - 1] : 0);
+ numvertices++;
+ break;
+ }
+
+ default:
+ // FIXME
+ }
+
+ /*
+ // invariant: after this loop, no two lines intersect other than at a vertex
+ // FIXME: cleanup
+ int index = numvertices - 2;
+ for(int i=0; i<Math.min(numvertices - 3, index); i++) {
+ for(int j = index; j < numvertices - 1; j++) {
+
+ // I'm not sure how to deal with vertical lines...
+ if (x[i+1] == x[i] || x[j+1] == x[j]) continue;
+
+ float islope = (y[i+1] - y[i]) / (x[i+1] - x[i]);
+ float jslope = (y[j+1] - y[j]) / (x[j+1] - x[j]);
+ if (islope == jslope) continue; // parallel lines can't intersect
+
+ float _x = (islope * x[i] - jslope * x[j] + y[j] - y[i]) / (islope - jslope);
+ float _y = islope * (_x - x[i]) + y[i];
+
+ if (_x > Math.min(x[i+1], x[i]) && _x < Math.max(x[i+1], x[i]) &&
+ _x > Math.min(x[j+1], x[j]) && _x < Math.max(x[j+1], x[j])) {
+ // FIXME: something's not right in here. See if we can do without fracturing line 'i'.
+ for(int k = ++numvertices; k>i; k--) { x[k] = x[k - 1]; y[k] = y[k - 1]; }
+ x[i+1] = _x;
+ y[i+1] = _y;
+ x[numvertices] = x[numvertices - 1]; x[numvertices - 1] = _x;
+ y[numvertices] = y[numvertices - 1]; y[numvertices - 1] = _y;
+ edges[numedges++] = numvertices - 1; numvertices++;
+ index++;
+ break; // actually 'continue' the outermost loop
+ }
+ }
+ }
+ */
+
+ }
+ }
+
+
+
+
+ // Rasterized Vector Path //////////////////////////////////////////////////////////////////////////////
+
+ /** a vector path */
+ public static class RasterPath {
+
+ // the vertices of this path
+ int[] x = new int[DEFAULT_PATHLEN];
+ int[] y = new int[DEFAULT_PATHLEN];
+ int numvertices = 0;
+
+ /**
+ * A list of the vertices on this path which *start* an *edge* (rather than a moveto), sorted by increasing y.
+ * example: x[edges[1]],y[edges[1]] - x[edges[i]+1],y[edges[i]+1] is the second-topmost edge
+ * note that if x[i],y[i] - x[i+1],y[i+1] is a MOVETO, then no element in edges will be equal to i
+ */
+ int[] edges = new int[DEFAULT_PATHLEN];
+ int numedges = 0;
+
+ /** translate a rasterized path */
+ public void translate(int dx, int dy) { for(int i=0; i<numvertices; i++) { x[i] += dx; y[i] += dy; } }
+
+ /** simple quicksort, from http://sourceforge.net/snippet/detail.php?type=snippet&id=100240 */
+ int sort(int left, int right, boolean partition) {
+ if (partition) {
+ int i, j, middle;
+ middle = (left + right) / 2;
+ int s = edges[right]; edges[right] = edges[middle]; edges[middle] = s;
+ for (i = left - 1, j = right; ; ) {
+ while (y[edges[++i]] < y[edges[right]]);
+ while (j > left && y[edges[--j]] > y[edges[right]]);
+ if (i >= j) break;
+ s = edges[i]; edges[i] = edges[j]; edges[j] = s;
+ }
+ s = edges[right]; edges[right] = edges[i]; edges[i] = s;
+ return i;
+ } else {
+ if (left >= right) return 0;
+ int p = sort(left, right, true);
+ sort(left, p - 1, false);
+ sort(p + 1, right, false);
+ return 0;
+ }
+ }
+
+ /** finds the x value at which the line intercepts the line y=_y */
+ private int intercept(int i, float _y, boolean includeTop, boolean includeBottom) {
+ if (includeTop ? (_y < Math.min(y[i], y[i+1])) : (_y <= Math.min(y[i], y[i+1])))
+ return Integer.MIN_VALUE;
+ if (includeBottom ? (_y > Math.max(y[i], y[i+1])) : (_y >= Math.max(y[i], y[i+1])))
+ return Integer.MIN_VALUE;
+ return (int)Math.round((((float)(x[i + 1] - x[i])) /
+ ((float)(y[i + 1] - y[i])) ) * ((float)(_y - y[i])) + x[i]);
+ }
+
+ /** fill the interior of the path */
+ public void fill(PixelBuffer buf, Paint paint) {
+ if (numedges == 0) return;
+ int y0 = y[edges[0]], y1 = y0;
+ boolean useEvenOdd = false;
+
+ // we iterate over all endpoints in increasing y-coordinate order
+ for(int index = 1; index<numedges; index++) {
+ int count = 0;
+
+ // we now examine the horizontal band between y=y0 and y=y1
+ y0 = y1;
+ y1 = y[edges[index]];
+ if (y0 == y1) continue;
+
+ // within this band, we iterate over all edges
+ int x0 = Integer.MIN_VALUE;
+ int leftSegment = -1;
+ while(true) {
+ int x1 = Integer.MAX_VALUE;
+ int rightSegment = Integer.MAX_VALUE;
+ for(int i=0; i<numedges; i++) {
+ if (y[edges[i]] == y[edges[i]+1]) continue; // ignore horizontal lines; they are irrelevant.
+ // we order the segments by the x-coordinate of their midpoint;
+ // since segments cannot intersect, this is a well-ordering
+ int i0 = intercept(edges[i], y0, true, false);
+ int i1 = intercept(edges[i], y1, false, true);
+ if (i0 == Integer.MIN_VALUE || i1 == Integer.MIN_VALUE) continue;
+ int midpoint = i0 + i1;
+ if (midpoint < x0) continue;
+ if (midpoint == x0 && i <= leftSegment) continue;
+ if (midpoint > x1) continue;
+ if (midpoint == x1 && i >= rightSegment) continue;
+ rightSegment = i;
+ x1 = midpoint;
+ }
+ if (leftSegment == rightSegment || rightSegment == Integer.MAX_VALUE) break;
+ if (leftSegment != -1)
+ if ((useEvenOdd && count % 2 != 0) || (!useEvenOdd && count != 0))
+ paint.fillTrapezoid(intercept(edges[leftSegment], y0, true, true),
+ intercept(edges[rightSegment], y0, true, true), y0,
+ intercept(edges[leftSegment], y1, true, true),
+ intercept(edges[rightSegment], y1, true, true), y1,
+ buf);
+ if (useEvenOdd) count++;
+ else count += (y[edges[rightSegment]] < y[edges[rightSegment]+1]) ? -1 : 1;
+ leftSegment = rightSegment; x0 = x1;
+ }
+ }
+ }
+
+ /** stroke the outline of the path */
+ public void stroke(PixelBuffer buf, int width, int color) { stroke(buf, width, color, null, 0, 0); }
+ public void stroke(PixelBuffer buf, int width, int color, String dashArray, int dashOffset, float segLength) {
+
+ if (dashArray == null) {
+ for(int i=0; i<numedges; i++)
+ buf.drawLine((int)x[edges[i]],
+ (int)y[edges[i]], (int)x[edges[i]+1], (int)y[edges[i]+1], width, color, false);
+ return;
+ }
+
+ float ratio = 1;
+ if (segLength > 0) {
+ float actualLength = 0;
+ for(int i=0; i<numvertices; i++) {
+ // skip over MOVETOs -- they do not contribute to path length
+ if (x[i] == x[i+1] && y[i] == y[i+1]) continue;
+ if (x[i+1] == x[i+2] && y[i+1] == y[i+2]) continue;
+ int x1 = x[i];
+ int x2 = x[i + 1];
+ int y1 = y[i];
+ int y2 = y[i + 1];
+ actualLength += java.lang.Math.sqrt((x2 - x1) * (x2 - x1) + (y2 - y1) * (y2 - y1));
+ }
+ ratio = actualLength / segLength;
+ }
+ PathTokenizer pt = new PathTokenizer(dashArray);
+ Vector v = new Vector();
+ while (pt.hasMoreTokens()) v.addElement(new Float(pt.parseFloat()));
+ float[] dashes = new float[v.size() % 2 == 0 ? v.size() : 2 * v.size()];
+ for(int i=0; i<dashes.length; i++) dashes[i] = ((Float)v.elementAt(i % v.size())).floatValue();
+ int dashpos = dashOffset;
+ boolean on = dashpos % 2 == 0;
+ for(int i=0; i<numvertices; i++) {
+ // skip over MOVETOs -- they do not contribute to path length
+ if (x[i] == x[i+1] && y[i] == y[i+1]) continue;
+ if (x[i+1] == x[i+2] && y[i+1] == y[i+2]) continue;
+ int x1 = (int)x[i];
+ int x2 = (int)x[i + 1];
+ int y1 = (int)y[i];
+ int y2 = (int)y[i + 1];
+ float segmentLength = (float)java.lang.Math.sqrt((x2 - x1) * (x2 - x1) + (y2 - y1) * (y2 - y1));
+ int _x1 = x1, _y1 = y1;
+ float pos = 0;
+ do {
+ pos = Math.min(segmentLength, pos + dashes[dashpos] * ratio);
+ if (pos != segmentLength) dashpos = (dashpos + 1) % dashes.length;
+ int _x2 = (int)((x2 * pos + x1 * (segmentLength - pos)) / segmentLength);
+ int _y2 = (int)((y2 * pos + y1 * (segmentLength - pos)) / segmentLength);
+ if (on) buf.drawLine(_x1, _y1, _x2, _y2, width, color, false);
+ on = !on;
+ _x1 = _x2; _y1 = _y2;
+ } while(pos < segmentLength);
+ }
+ }
+
+ // FEATURE: make this faster and cache it; also deal with negative coordinates
+ public int boundingBoxWidth() {
+ int ret = 0;
+ for(int i=0; i<numvertices; i++) ret = Math.max(ret, x[i]);
+ return ret;
+ }
+
+ // FEATURE: make this faster and cache it; also deal with negative coordinates
+ public int boundingBoxHeight() {
+ int ret = 0;
+ for(int i=0; i<numvertices; i++) ret = Math.max(ret, y[i]);
+ return ret;
+ }
+ }
+
+
+ // Paint //////////////////////////////////////////////////////////////////////////////
+
+ public static interface Paint {
+ public abstract void
+ fillTrapezoid(int tx1, int tx2, int ty1, int tx3, int tx4, int ty2, PixelBuffer buf);
+ }
+
+ public static class SingleColorPaint implements Paint {
+ int color;
+ public SingleColorPaint(int color) { this.color = color; }
+ public void fillTrapezoid(int x1, int x2, int y1, int x3, int x4, int y2, PixelBuffer buf) {
+ buf.fillTrapezoid(x1, x2, y1, x3, x4, y2, color);
+ }
+ }
+
+}
+
+
+
+
+
+
+
+
+
+ /*
+ public static abstract class GradientPaint extends Paint {
+ public GradientPaint(boolean reflect, boolean repeat, Affine gradientTransform,
+ int[] stop_colors, float[] stop_offsets) {
+ this.reflect = reflect; this.repeat = repeat;
+ this.gradientTransform = gradientTransform;
+ this.stop_colors = stop_colors;
+ this.stop_offsets = stop_offsets;
+ }
+ Affine gradientTransform = Affine.identity();
+ boolean useBoundingBox = false; // FIXME not supported
+ boolean patternUseBoundingBox = false; // FIXME not supported
+
+ // it's invalid for both of these to be true
+ boolean reflect = false; // FIXME not supported
+ boolean repeat = false; // FIXME not supported
+ int[] stop_colors;
+ float[] stop_offsets;
+
+ public void fillTrapezoid(float tx1, float tx2, float ty1, float tx3, float tx4, float ty2, PixelBuffer buf) {
+ Affine a = buf.a;
+ Affine inverse = a.copy().invert();
+ float slope1 = (tx3 - tx1) / (ty2 - ty1);
+ float slope2 = (tx4 - tx2) / (ty2 - ty1);
+ for(float y=ty1; y<ty2; y++) {
+ float _x1 = (y - ty1) * slope1 + tx1;
+ float _x2 = (y - ty1) * slope2 + tx2;
+ if (_x1 > _x2) { float _x0 = _x1; _x1 = _x2; _x2 = _x0; }
+
+ for(float x=_x1; x<_x2; x++) {
+
+ float distance = isLinear ?
+ // length of projection of <x,y> onto the gradient vector == {<x,y> \dot {grad \over |grad|}}
+ (x * (x2 - x1) + y * (y2 - y1)) / (float)Math.sqrt((x2 - x1) * (x2 - x1) + (y2 - y1) * (y2 - y1)) :
+
+ // radial form is simple! FIXME, not quite right
+ (float)Math.sqrt((x - cx) * (x - cx) + (y - cy) * (y - cy));
+
+ // FIXME: offsets are 0..1, not 0..length(gradient)
+ int i = 0; for(; i<stop_offsets.length; i++) if (distance < stop_offsets[i]) break;
+
+ // FIXME: handle points beyond the bounds
+ if (i < 0 || i >= stop_offsets.length) continue;
+
+ // gradate from offsets[i - 1] to offsets[i]
+ float percentage = ((distance - stop_offsets[i - 1]) / (stop_offsets[i] - stop_offsets[i - 1]));
+
+ int a = (int)((((stop_colors[i] >> 24) & 0xff) - ((stop_colors[i - 1] >> 24) & 0xff)) * percentage) +
+ ((stop_colors[i - 1] >> 24) & 0xff);
+ int r = (int)((((stop_colors[i] >> 16) & 0xff) - ((stop_colors[i - 1] >> 16) & 0xff)) * percentage) +
+ ((stop_colors[i - 1] >> 16) & 0xff);
+ int g = (int)((((stop_colors[i] >> 8) & 0xff) - ((stop_colors[i - 1] >> 8) & 0xff)) * percentage) +
+ ((stop_colors[i - 1] >> 8) & 0xff);
+ int b = (int)((((stop_colors[i] >> 0) & 0xff) - ((stop_colors[i - 1] >> 0) & 0xff)) * percentage) +
+ ((stop_colors[i - 1] >> 0) & 0xff);
+ int argb = (a << 24) | (r << 16) | (g << 8) | b;
+ buf.drawPoint((int)x, (int)Math.floor(y), argb);
+ }
+ }
+ }
+ }
+
+ public static class LinearGradientPaint extends GradientPaint {
+ public LinearGradientPaint(float x1, float y1, float x2, float y2, boolean reflect, boolean repeat,
+ Affine gradientTransform, int[] stop_colors, float[] stop_offsets) {
+ super(reflect, repeat, gradientTransform, stop_colors, stop_offsets);
+ this.x1 = x1; this.x2 = x2; this.y1 = y1; this.y2 = y2;
+ }
+ float x1 = 0, y1 = 0, x2 = 300, y2 = 300;
+ }
+
+ public static class RadialGradientPaint extends GradientPaint {
+ public RadialGradientPaint(float cx, float cy, float fx, float fy, float r, boolean reflect, boolean repeat,
+ Affine gradientTransform, int[] stop_colors, float[] stop_offsets) {
+ super(reflect, repeat, gradientTransform, stop_colors, stop_offsets);
+ this.cx = cx; this.cy = cy; this.fx = fx; this.fy = fy; this.r = r;
+ }
+
+ float cx, cy, r, fx, fy;
+
+ }
+ */
+
projects / org.ibex.core.git / blobdiff