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refactor TileClipper

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- fix: TileClipper check len<6 before len==0
This commit is contained in:
Hannes Janetzek 2014-04-20 00:18:53 +02:00
parent d263089c06
commit d6b95c936a
1 changed files with 128 additions and 98 deletions
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226
vtm/src/org/oscim/utils/geom/TileClipper.java
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@ -55,7 +55,6 @@ public class TileClipper {
if (geom.isPoly()) {
GeometryBuffer out = mGeomOut;
out.clear();
clipEdge(geom, out, LineClipper.LEFT);
@ -102,26 +101,39 @@ public class TileClipper {
int pointPos = 0;
for (int i = 0, n = in.index.length; i < n; i++) {
int len = in.index[i];
for (int indexPos = 0, n = in.index.length; indexPos < n; indexPos++) {
int len = in.index[indexPos];
if (len < 0)
break;
if (len < 6) {
pointPos += len;
continue;
}
if (len == 0) {
out.startPolygon();
outer = true;
continue;
}
if (len < 6) {
pointPos += len;
continue;
}
if (!outer)
out.startHole();
clipRing(i, pointPos, in, out, edge);
switch (edge) {
case LineClipper.LEFT:
clipRingLeft(indexPos, pointPos, in, out);
break;
case LineClipper.RIGHT:
clipRingRight(indexPos, pointPos, in, out);
break;
case LineClipper.TOP:
clipRingTop(indexPos, pointPos, in, out);
break;
case LineClipper.BOTTOM:
clipRingBottom(indexPos, pointPos, in, out);
break;
}
//if (out.index[i] < 6) {
// out.index[i] = 0;
@ -134,10 +146,116 @@ public class TileClipper {
outer = false;
}
return true;
}
private void clipRingLeft(int indexPos, int pointPos, GeometryBuffer in, GeometryBuffer out) {
int end = in.index[indexPos] + pointPos;
float px = in.points[end - 2];
float py = in.points[end - 1];
for (int i = pointPos; i < end;) {
float cx = in.points[i++];
float cy = in.points[i++];
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));
}
/* else skip point */
}
px = cx;
py = cy;
}
}
private void clipRingRight(int indexPos, int pointPos, GeometryBuffer in, GeometryBuffer out) {
int len = in.index[indexPos] + 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++];
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));
}
}
px = cx;
py = cy;
}
}
private void clipRingTop(int indexPos, int pointPos, GeometryBuffer in, GeometryBuffer out) {
int len = in.index[indexPos] + 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++];
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);
}
}
px = cx;
py = cy;
}
}
private void clipRingBottom(int indexPos, int pointPos, GeometryBuffer in, GeometryBuffer out) {
int len = in.index[indexPos] + 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++];
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);
}
}
px = cx;
py = cy;
}
}
private int clipLine(GeometryBuffer in, GeometryBuffer out) {
int pointPos = 0;
@ -209,92 +327,4 @@ public class TileClipper {
return numLines;
}
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;
}
}