Index: include/gpu/GrClip.h |
diff --git a/include/gpu/GrClip.h b/include/gpu/GrClip.h |
index ab83441f41e28692aca17183ceae27528fb89699..1cb1a2bcf60a9399da4a356ad5941cdb8a82febc 100644 |
--- a/include/gpu/GrClip.h |
+++ b/include/gpu/GrClip.h |
@@ -113,25 +113,76 @@ public: |
virtual ~GrClip() {} |
-protected: |
/** |
- * Returns true if a clip can safely disable its scissor test for a particular draw. |
+ * This is the maximum distance that a draw may extend beyond a clip's boundary and still count |
+ * count as "on the other side". We leave some slack because floating point rounding error is |
+ * likely to blame. The rationale for 1e-3 is that in the coverage case (and barring unexpected |
+ * rounding), as long as coverage stays within 0.5 * 1/256 of its intended value it shouldn't |
+ * have any effect on the final pixel values. |
*/ |
- static bool CanIgnoreScissor(const SkIRect& scissorRect, const SkRect& drawBounds) { |
- // This is the maximum distance that a draw may extend beyond a clip's scissor and still |
- // count as inside. We use a sloppy compare because the draw may have chosen its bounds in a |
- // different coord system. The rationale for 1e-3 is that in the coverage case (and barring |
- // unexpected rounding), as long as coverage stays below 0.5 * 1/256 we ought to be OK. |
- constexpr SkScalar fuzz = 1e-3f; |
- SkASSERT(!scissorRect.isEmpty()); |
- SkASSERT(!drawBounds.isEmpty()); |
- return scissorRect.fLeft <= drawBounds.fLeft + fuzz && |
- scissorRect.fTop <= drawBounds.fTop + fuzz && |
- scissorRect.fRight >= drawBounds.fRight - fuzz && |
- scissorRect.fBottom >= drawBounds.fBottom - fuzz; |
- } |
- |
- friend class GrClipMaskManager; |
+ constexpr static SkScalar kBoundsTolerance = 1e-3f; |
+ |
+ /** |
+ * Returns true if the given query bounds count as entirely inside the clip. |
+ * |
+ * @param innerClipBounds device-space rect contained by the clip (SkRect or SkIRect). |
+ * @param queryBounds device-space bounds of the query region. |
+ */ |
+ template<typename TRect> constexpr static bool IsInsideClip(const TRect& innerClipBounds, |
+ const SkRect& queryBounds) { |
+ return innerClipBounds.fRight - innerClipBounds.fLeft >= kBoundsTolerance && |
+ innerClipBounds.fBottom - innerClipBounds.fTop >= kBoundsTolerance && |
+ innerClipBounds.fLeft <= queryBounds.fLeft + kBoundsTolerance && |
+ innerClipBounds.fTop <= queryBounds.fTop + kBoundsTolerance && |
+ innerClipBounds.fRight >= queryBounds.fRight - kBoundsTolerance && |
+ innerClipBounds.fBottom >= queryBounds.fBottom - kBoundsTolerance; |
+ } |
+ |
+ /** |
+ * Returns true if the given query bounds count as entirely outside the clip. |
+ * |
+ * @param outerClipBounds device-space rect that contains the clip (SkRect or SkIRect). |
+ * @param queryBounds device-space bounds of the query region. |
+ */ |
+ template<typename TRect> constexpr static bool IsOutsideClip(const TRect& outerClipBounds, |
+ const SkRect& queryBounds) { |
+ return outerClipBounds.fRight - outerClipBounds.fLeft < kBoundsTolerance || |
+ outerClipBounds.fBottom - outerClipBounds.fTop < kBoundsTolerance || |
+ outerClipBounds.fLeft > queryBounds.fRight - kBoundsTolerance || |
+ outerClipBounds.fTop > queryBounds.fBottom - kBoundsTolerance || |
+ outerClipBounds.fRight < queryBounds.fLeft + kBoundsTolerance || |
+ outerClipBounds.fBottom < queryBounds.fTop + kBoundsTolerance; |
+ } |
+ |
+ /** |
+ * Returns the minimal integer rect that counts as containing a given set of bounds. |
+ */ |
+ static SkIRect GetPixelIBounds(const SkRect& bounds) { |
+ return SkIRect::MakeLTRB(SkScalarFloorToInt(bounds.fLeft + kBoundsTolerance), |
+ SkScalarFloorToInt(bounds.fTop + kBoundsTolerance), |
+ SkScalarCeilToInt(bounds.fRight - kBoundsTolerance), |
+ SkScalarCeilToInt(bounds.fBottom - kBoundsTolerance)); |
+ } |
+ |
+ /** |
+ * Returns the minimal pixel-aligned rect that counts as containing a given set of bounds. |
+ */ |
+ static SkRect GetPixelBounds(const SkRect& bounds) { |
+ return SkRect::MakeLTRB(SkScalarFloorToScalar(bounds.fLeft + kBoundsTolerance), |
+ SkScalarFloorToScalar(bounds.fTop + kBoundsTolerance), |
+ SkScalarCeilToScalar(bounds.fRight - kBoundsTolerance), |
+ SkScalarCeilToScalar(bounds.fBottom - kBoundsTolerance)); |
+ } |
+ |
+ /** |
+ * Returns true if the given rect counts as aligned with pixel boundaries. |
+ */ |
+ static bool IsPixelAligned(const SkRect& rect) { |
+ return SkScalarAbs(SkScalarRoundToScalar(rect.fLeft) - rect.fLeft) <= kBoundsTolerance && |
+ SkScalarAbs(SkScalarRoundToScalar(rect.fTop) - rect.fTop) <= kBoundsTolerance && |
+ SkScalarAbs(SkScalarRoundToScalar(rect.fRight) - rect.fRight) <= kBoundsTolerance && |
+ SkScalarAbs(SkScalarRoundToScalar(rect.fBottom) - rect.fBottom) <= kBoundsTolerance; |
+ } |
}; |
/** |