Plumb fast rectangle blur code into the skia mask filter
Review URL: https://codereview.chromium.org/12387099
git-svn-id: http://skia.googlecode.com/svn/trunk@8074 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/effects/SkBlurMask.cpp b/src/effects/SkBlurMask.cpp
index 413e8c0..19a538a 100644
--- a/src/effects/SkBlurMask.cpp
+++ b/src/effects/SkBlurMask.cpp
@@ -1185,23 +1185,28 @@
return 0.4375f + (-x3 / 6.0f - 3.0f * x2 * 0.25f - 1.125f * x);
}
-/*
- compute_profile allocates and fills in an array of floating
+// Compute the size of the array allocated for the profile.
+
+static int compute_profile_size(SkScalar radius) {
+ return SkScalarRoundToInt(radius * 3);
+
+}
+
+/* compute_profile allocates and fills in an array of floating
point values between 0 and 255 for the profile signature of
a blurred half-plane with the given blur radius. Since we're
going to be doing screened multiplications (i.e., 1 - (1-x)(1-y))
all the time, we actually fill in the profile pre-inverted
(already done 255-x).
- The function returns the size of the array allocated for the
- profile. It's the responsibility of the caller to delete the
+ It's the responsibility of the caller to delete the
memory returned in profile_out.
*/
-static int compute_profile(SkScalar radius, unsigned int **profile_out) {
- int size = SkScalarRoundToInt(radius * 3);
+static void compute_profile(SkScalar radius, unsigned int **profile_out) {
+ int size = compute_profile_size(radius);
+
int center = size >> 1;
-
unsigned int *profile = SkNEW_ARRAY(unsigned int, size);
float invr = 1.f/radius;
@@ -1214,7 +1219,6 @@
}
*profile_out = profile;
- return size;
}
// TODO MAYBE: Maintain a profile cache to avoid recomputing this for
@@ -1236,19 +1240,16 @@
bool SkBlurMask::BlurRect(SkMask *dst, const SkRect &src,
SkScalar provided_radius, Style style,
- SkIPoint *margin) {
+ SkIPoint *margin, SkMask::CreateMode createMode) {
int profile_size;
- unsigned int *profile;
- float radius = SkScalarToFloat( SkScalarMul( provided_radius, kBlurRadiusFudgeFactor ) );
+ float radius = SkScalarToFloat(SkScalarMul(provided_radius, kBlurRadiusFudgeFactor));
// adjust blur radius to match interpretation from boxfilter code
- radius = (radius + .5f) *2.f;
+ radius = (radius + .5f) * 2.f;
- profile_size = compute_profile( radius, &profile );
-
- SkAutoTDeleteArray<unsigned int> ada(profile);
-
+ profile_size = compute_profile_size(radius);
+
int pad = profile_size/2;
if (margin) {
margin->set( pad, pad );
@@ -1259,20 +1260,35 @@
int shadow_right = (int)(src.width()) + pad;
int shadow_bottom = (int)(src.height()) + pad;
- dst->fBounds.set(shadow_left, shadow_top, shadow_right, shadow_bottom);
+ dst->fBounds.set(shadow_left + src.fLeft,
+ shadow_top + src.fTop,
+ shadow_right + src.fRight,
+ shadow_bottom + src.fBottom);
dst->fRowBytes = dst->fBounds.width();
dst->fFormat = SkMask::kA8_Format;
dst->fImage = NULL;
-
+
+ int sw = SkScalarFloorToInt(src.width());
+ int sh = SkScalarFloorToInt(src.height());
+
+ if (createMode == SkMask::kJustComputeBounds_CreateMode) {
+ if (style == kInner_Style) {
+ dst->fBounds.set(0, 0, sw, sh); // restore trimmed bounds
+ dst->fRowBytes = sw;
+ }
+ return true;
+ }
+ unsigned int *profile = NULL;
+
+ compute_profile(radius, &profile);
+ SkAutoTDeleteArray<unsigned int> ada(profile);
+
size_t dstSize = dst->computeImageSize();
if (0 == dstSize) {
return false; // too big to allocate, abort
}
- int sw = SkScalarFloorToInt(src.width());
- int sh = SkScalarFloorToInt(src.height());
-
uint8_t* dp = SkMask::AllocImage(dstSize);
dst->fImage = dp;