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-rw-r--r--src/effects/SkBlurMask.cpp70
1 files changed, 34 insertions, 36 deletions
diff --git a/src/effects/SkBlurMask.cpp b/src/effects/SkBlurMask.cpp
index f61536e65a..32a3d20d31 100644
--- a/src/effects/SkBlurMask.cpp
+++ b/src/effects/SkBlurMask.cpp
@@ -671,7 +671,7 @@ static float gaussianIntegral(float x) {
return 0.4375f + (-x3 / 6.0f - 3.0f * x2 * 0.25f - 1.125f * x);
}
-/* ComputeBlurProfile allocates and fills in an array of floating
+/* 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))
@@ -682,11 +682,11 @@ static float gaussianIntegral(float x) {
memory returned in profile_out.
*/
-void SkBlurMask::ComputeBlurProfile(SkScalar sigma, uint8_t **profile_out) {
+static void compute_profile(SkScalar sigma, unsigned int **profile_out) {
int size = SkScalarCeilToInt(6*sigma);
int center = size >> 1;
- uint8_t *profile = SkNEW_ARRAY(uint8_t, size);
+ unsigned int *profile = SkNEW_ARRAY(unsigned int, size);
float invr = 1.f/(2*sigma);
@@ -707,7 +707,7 @@ void SkBlurMask::ComputeBlurProfile(SkScalar sigma, uint8_t **profile_out) {
// Implementation adapted from Michael Herf's approach:
// http://stereopsis.com/shadowrect/
-uint8_t SkBlurMask::ProfileLookup(const uint8_t *profile, int loc, int blurred_width, int sharp_width) {
+static inline unsigned int profile_lookup( unsigned int *profile, int loc, int blurred_width, int sharp_width ) {
int dx = SkAbs32(((loc << 1) + 1) - blurred_width) - sharp_width; // how far are we from the original edge?
int ox = dx >> 1;
if (ox < 0) {
@@ -717,30 +717,6 @@ uint8_t SkBlurMask::ProfileLookup(const uint8_t *profile, int loc, int blurred_w
return profile[ox];
}
-void SkBlurMask::ComputeBlurredScanline(uint8_t *pixels, const uint8_t *profile,
- unsigned int width, SkScalar sigma) {
-
- unsigned int profile_size = SkScalarCeilToInt(6*sigma);
- SkAutoTMalloc<uint8_t> horizontalScanline(width);
-
- unsigned int sw = width - profile_size;
- // nearest odd number less than the profile size represents the center
- // of the (2x scaled) profile
- int center = ( profile_size & ~1 ) - 1;
-
- int w = sw - center;
-
- for (unsigned int x = 0 ; x < width ; ++x) {
- if (profile_size <= sw) {
- pixels[x] = ProfileLookup(profile, x, width, w);
- } else {
- float span = float(sw)/(2*sigma);
- float giX = 1.5f - (x+.5f)/(2*sigma);
- pixels[x] = (uint8_t) (255 * (gaussianIntegral(giX) - gaussianIntegral(giX + span)));
- }
- }
-}
-
bool SkBlurMask::BlurRect(SkMask *dst, const SkRect &src,
SkScalar radius, Style style,
SkIPoint *margin, SkMask::CreateMode createMode) {
@@ -781,10 +757,10 @@ bool SkBlurMask::BlurRect(SkScalar sigma, SkMask *dst,
}
return true;
}
- uint8_t *profile = NULL;
+ unsigned int *profile = NULL;
- ComputeBlurProfile(sigma, &profile);
- SkAutoTDeleteArray<uint8_t> ada(profile);
+ compute_profile(sigma, &profile);
+ SkAutoTDeleteArray<unsigned int> ada(profile);
size_t dstSize = dst->computeImageSize();
if (0 == dstSize) {
@@ -798,17 +774,39 @@ bool SkBlurMask::BlurRect(SkScalar sigma, SkMask *dst,
int dstHeight = dst->fBounds.height();
int dstWidth = dst->fBounds.width();
+ // nearest odd number less than the profile size represents the center
+ // of the (2x scaled) profile
+ int center = ( profile_size & ~1 ) - 1;
+
+ int w = sw - center;
+ int h = sh - center;
+
uint8_t *outptr = dp;
SkAutoTMalloc<uint8_t> horizontalScanline(dstWidth);
- SkAutoTMalloc<uint8_t> verticalScanline(dstHeight);
-
- ComputeBlurredScanline(horizontalScanline, profile, dstWidth, sigma);
- ComputeBlurredScanline(verticalScanline, profile, dstHeight, sigma);
+
+ for (int x = 0 ; x < dstWidth ; ++x) {
+ if (profile_size <= sw) {
+ horizontalScanline[x] = profile_lookup(profile, x, dstWidth, w);
+ } else {
+ float span = float(sw)/(2*sigma);
+ float giX = 1.5f - (x+.5f)/(2*sigma);
+ horizontalScanline[x] = (uint8_t) (255 * (gaussianIntegral(giX) - gaussianIntegral(giX + span)));
+ }
+ }
for (int y = 0 ; y < dstHeight ; ++y) {
+ unsigned int profile_y;
+ if (profile_size <= sh) {
+ profile_y = profile_lookup(profile, y, dstHeight, h);
+ } else {
+ float span = float(sh)/(2*sigma);
+ float giY = 1.5f - (y+.5f)/(2*sigma);
+ profile_y = (uint8_t) (255 * (gaussianIntegral(giY) - gaussianIntegral(giY + span)));
+ }
+
for (int x = 0 ; x < dstWidth ; x++) {
- unsigned int maskval = SkMulDiv255Round(horizontalScanline[x], verticalScanline[y]);
+ unsigned int maskval = SkMulDiv255Round(horizontalScanline[x], profile_y);
*(outptr++) = maskval;
}
}