private boolean clipEdge(GeometryBuffer in, GeometryBuffer out, int edge) {
out.startPolygon();
boolean outer = true;
int pointPos = 0;
for (int i = 0, n = in.index.length; i < n; i++) {
int len = in.index[i];
if (len < 0) break;
if (len < 6) {
pointPos += len;
continue;
}
if (len == 0) {
out.startPolygon();
outer = true;
continue;
}
if (!outer) out.startHole();
clipRing(i, pointPos, in, out, edge);
// if (out.index[i] < 6) {
// out.index[i] = 0;
// //if (out.indexPos > 0)
// // out.indexPos--;
// // TODO if outer skip holes
// }
pointPos += len;
outer = false;
}
return true;
}
public GridRenderer(int numLines, LineStyle lineStyle, TextStyle textStyle) {
int size = Tile.SIZE;
// not needed to set but we know:
// 16 lines 'a' two points
mLines = new GeometryBuffer(2 * 16, 16);
float pos = -size * 4;
// 8 vertical lines
for (int i = 0; i < 8 * numLines; i++) {
float x = pos + i * size / numLines;
mLines.startLine();
mLines.addPoint(x, pos);
mLines.addPoint(x, pos + size * 8);
}
// 8 horizontal lines
for (int j = 0; j < 8 * numLines; j++) {
float y = pos + j * size / numLines;
mLines.startLine();
mLines.addPoint(pos, y);
mLines.addPoint(pos + size * 8, y);
}
mText = textStyle;
if (mText != null) {
mTextLayer = layers.addTextLayer(new TextLayer());
} else {
mTextLayer = null;
}
mLineLayer = layers.addLineLayer(0, lineStyle);
mLineLayer.addLine(mLines);
mStringBuffer = new StringBuffer(32);
}
private boolean clipRing(
int indexPos, int pointPos, GeometryBuffer in, GeometryBuffer out, int edge) {
int len = in.index[indexPos];
if (len < 6) return false;
len += pointPos;
float px = in.points[len - 2];
float py = in.points[len - 1];
for (int i = pointPos; i < len; ) {
float cx = in.points[i++];
float cy = in.points[i++];
switch (edge) {
case LineClipper.LEFT:
if (cx > minX) {
// current is inside
if (px > minX) {
// previous was inside
out.addPoint(cx, cy);
} else {
// previous was outside, add edge point
out.addPoint(minX, py + (cy - py) * (minX - px) / (cx - px));
out.addPoint(cx, cy);
}
} else {
if (px > minX) {
// previous was inside, add edge point
out.addPoint(minX, py + (cy - py) * (minX - px) / (cx - px));
}
}
break;
case LineClipper.RIGHT:
if (cx < maxX) {
if (px < maxX) {
out.addPoint(cx, cy);
} else {
out.addPoint(maxX, py + (cy - py) * (maxX - px) / (cx - px));
out.addPoint(cx, cy);
}
} else {
if (px < maxX) {
out.addPoint(maxX, py + (cy - py) * (maxX - px) / (cx - px));
}
}
break;
case LineClipper.BOTTOM:
if (cy > minY) {
if (py > minY) {
out.addPoint(cx, cy);
} else {
out.addPoint(px + (cx - px) * (minY - py) / (cy - py), minY);
out.addPoint(cx, cy);
}
} else {
if (py > minY) {
out.addPoint(px + (cx - px) * (minY - py) / (cy - py), minY);
}
}
break;
case LineClipper.TOP:
if (cy < maxY) {
if (py < maxY) {
out.addPoint(cx, cy);
} else {
out.addPoint(px + (cx - px) * (maxY - py) / (cy - py), maxY);
out.addPoint(cx, cy);
}
} else {
if (py < maxY) {
out.addPoint(px + (cx - px) * (maxY - py) / (cy - py), maxY);
}
}
break;
}
px = cx;
py = cy;
}
return true;
}
public boolean clip(GeometryBuffer geom) {
if (geom.isPoly()) {
GeometryBuffer out = mGeomOut;
out.clear();
clipEdge(geom, out, LineClipper.LEFT);
geom.clear();
clipEdge(out, geom, LineClipper.TOP);
out.clear();
clipEdge(geom, out, LineClipper.RIGHT);
geom.clear();
clipEdge(out, geom, LineClipper.BOTTOM);
if ((geom.indexPos == 0) && (geom.index[0] < 6)) return false;
} else if (geom.isLine()) {
GeometryBuffer out = mGeomOut;
out.clear();
int numLines = clipLine(geom, out);
short idx[] = geom.ensureIndexSize(numLines + 1, false);
System.arraycopy(out.index, 0, idx, 0, numLines);
geom.index[numLines] = -1;
float pts[] = geom.ensurePointSize(out.pointPos >> 1, false);
System.arraycopy(out.points, 0, pts, 0, out.pointPos);
geom.indexPos = out.indexPos;
geom.pointPos = out.pointPos;
if ((geom.indexPos == 0) && (geom.index[0] < 4)) return false;
}
return true;
}
private int clipLine(GeometryBuffer in, GeometryBuffer out) {
int pointPos = 0;
int numLines = 0;
for (int i = 0, n = in.index.length; i < n; i++) {
int len = in.index[i];
if (len < 0) break;
if (len < 4) {
pointPos += len;
continue;
}
if (len == 0) {
continue;
}
int inPos = pointPos;
int end = inPos + len;
float prevX = in.points[inPos + 0];
float prevY = in.points[inPos + 1];
boolean inside = mLineClipper.clipStart(prevX, prevY);
if (inside) {
out.startLine();
out.addPoint(prevX, prevY);
numLines++;
}
for (inPos += 2; inPos < end; inPos += 2) {
// get the current way point coordinates
float curX = in.points[inPos];
float curY = in.points[inPos + 1];
int clip;
if ((clip = mLineClipper.clipNext(curX, curY)) != 0) {
// System.out.println(inside + " clip: " + clip + " "
// + Arrays.toString(mLineClipper.out));
if (clip < 0) {
if (inside) {
// previous was inside
out.addPoint(mLineClipper.out[2], mLineClipper.out[3]);
inside = false;
} else {
// previous was outside
out.startLine();
numLines++;
out.addPoint(mLineClipper.out[0], mLineClipper.out[1]);
out.addPoint(mLineClipper.out[2], mLineClipper.out[3]);
inside = mLineClipper.clipStart(curX, curY);
}
} else {
out.addPoint(curX, curY);
}
} else {
inside = false;
}
}
pointPos += len;
}
return numLines;
}