Add abort logging for huge scales and tessellation recursion depth
bug:15615144
Change-Id: I275732eb97f9d5179beed23eecd2ee3cc7112e10
diff --git a/libs/hwui/PathTessellator.cpp b/libs/hwui/PathTessellator.cpp
index 59e15e1..310b107 100644
--- a/libs/hwui/PathTessellator.cpp
+++ b/libs/hwui/PathTessellator.cpp
@@ -57,17 +57,26 @@
#define ROUND_CAP_THRESH 0.25f
#define PI 3.1415926535897932f
+// temporary error thresholds
+#define ERROR_DEPTH 20
+#define ERROR_SCALE 1e10
+#define ERROR_SQR_INV_THRESH 1e-20
+
void PathTessellator::extractTessellationScales(const Matrix4& transform,
float* scaleX, float* scaleY) {
- *scaleX = 1.0f;
- *scaleY = 1.0f;
- if (CC_UNLIKELY(!transform.isPureTranslate())) {
+ if (CC_LIKELY(transform.isPureTranslate())) {
+ *scaleX = 1.0f;
+ *scaleY = 1.0f;
+ } else {
float m00 = transform.data[Matrix4::kScaleX];
float m01 = transform.data[Matrix4::kSkewY];
float m10 = transform.data[Matrix4::kSkewX];
float m11 = transform.data[Matrix4::kScaleY];
*scaleX = sqrt(m00 * m00 + m01 * m01);
*scaleY = sqrt(m10 * m10 + m11 * m11);
+
+ LOG_ALWAYS_FATAL_IF(*scaleX > ERROR_SCALE || *scaleY > ERROR_SCALE,
+ "scales %e x %e too large for tessellation", *scaleX, *scaleY);
}
}
@@ -92,10 +101,12 @@
public:
PaintInfo(const SkPaint* paint, const mat4& transform) :
style(paint->getStyle()), cap(paint->getStrokeCap()), isAA(paint->isAntiAlias()),
- inverseScaleX(1.0f), inverseScaleY(1.0f),
halfStrokeWidth(paint->getStrokeWidth() * 0.5f), maxAlpha(1.0f) {
// compute inverse scales
- if (CC_UNLIKELY(!transform.isPureTranslate())) {
+ if (CC_LIKELY(transform.isPureTranslate())) {
+ inverseScaleX = 1.0f;
+ inverseScaleY = 1.0f;
+ } else {
float scaleX, scaleY;
PathTessellator::extractTessellationScales(transform, &scaleX, &scaleY);
inverseScaleX = (scaleX != 0) ? (1.0f / scaleX) : 1.0f;
@@ -922,6 +933,9 @@
Vector<Vertex>& outputVertices) {
ATRACE_CALL();
+ LOG_ALWAYS_FATAL_IF(sqrInvScaleX < ERROR_SQR_INV_THRESH || sqrInvScaleY < ERROR_SQR_INV_THRESH,
+ "Invalid scale factors used for approx %e, %e", sqrInvScaleX, sqrInvScaleY);
+
// TODO: to support joins other than sharp miter, join vertices should be labelled in the
// perimeter, or resolved into more vertices. Reconsider forceClose-ing in that case.
SkPath::Iter iter(path, forceClose);
@@ -975,14 +989,14 @@
// Bezier approximation
///////////////////////////////////////////////////////////////////////////////
-// Depth at which recursion is aborted
-#define ABORT_DEPTH 20
-
void PathTessellator::recursiveCubicBezierVertices(
float p1x, float p1y, float c1x, float c1y,
float p2x, float p2y, float c2x, float c2y,
float sqrInvScaleX, float sqrInvScaleY, float thresholdSquared,
Vector<Vertex>& outputVertices, int depth) {
+ LOG_ALWAYS_FATAL_IF(depth >= ERROR_DEPTH, "ERROR DEPTH exceeded: cubic approx, invscale %e x %e, vertcount %d",
+ sqrInvScaleX, sqrInvScaleY, outputVertices.size());
+
float dx = p2x - p1x;
float dy = p2y - p1y;
float d1 = fabs((c1x - p2x) * dy - (c1y - p2y) * dx);
@@ -990,8 +1004,7 @@
float d = d1 + d2;
// multiplying by sqrInvScaleY/X equivalent to multiplying in dimensional scale factors
-
- if (depth >= ABORT_DEPTH || d * d < thresholdSquared * (dx * dx * sqrInvScaleY + dy * dy * sqrInvScaleX)) {
+ if (d * d < thresholdSquared * (dx * dx * sqrInvScaleY + dy * dy * sqrInvScaleX)) {
// below thresh, draw line by adding endpoint
pushToVector(outputVertices, p2x, p2y);
} else {
@@ -1029,11 +1042,14 @@
float cx, float cy,
float sqrInvScaleX, float sqrInvScaleY, float thresholdSquared,
Vector<Vertex>& outputVertices, int depth) {
+ LOG_ALWAYS_FATAL_IF(depth >= ERROR_DEPTH, "ERROR_DEPTH exceeded: quadratic approx, invscale %e x %e, vertcount %d",
+ sqrInvScaleX, sqrInvScaleY, outputVertices.size());
+
float dx = bx - ax;
float dy = by - ay;
float d = (cx - bx) * dy - (cy - by) * dx;
- if (depth >= ABORT_DEPTH || d * d < thresholdSquared * (dx * dx * sqrInvScaleY + dy * dy * sqrInvScaleX)) {
+ if (d * d < thresholdSquared * (dx * dx * sqrInvScaleY + dy * dy * sqrInvScaleX)) {
// below thresh, draw line by adding endpoint
pushToVector(outputVertices, bx, by);
} else {