ios fixes
skia_ios.mm
Get the app's Documents directory and pass use it to set the resource path.
This is a quick hack which will be replaced by a new application that is
a tiny shim around a command line tool.
SkImageEncoder.h
SkForceLinking.cpp
SkImageDecoder_CG.cpp
Add support for FORCE_LINKING so iOS sees the PNG encoder and others.
SkFloatBits.cpp
SkPoint.cpp
Handle denormalized numbers that are floored by the iOS ARM processor.
SkImageDecoder_iOS.mm
Remove empty encoder factory.
SkTouchGesture.cpp
Return early on empty state on touch rather than aborting (crashing)
JpegTest.cpp
Hal via stackoverflow.com says partial jpegs can be gray as well.
skia_test.cpp
Remove crash handler call for now to avoid link failure.
OverwriteLine.h
Remove fancy line overwrite for iOS.
Resources.cpp
Add interface to set resource directory based on runtime query.
BUG=skia:2736 skia:2737 skia:2738
R=reed@google.com, halcanary@google.com, mtklein@google.com, tfarina@chromium.org
Author: caryclark@google.com
Review URL: https://codereview.chromium.org/373383003
diff --git a/src/core/SkFloatBits.cpp b/src/core/SkFloatBits.cpp
index 39b51ab..6b35a75 100644
--- a/src/core/SkFloatBits.cpp
+++ b/src/core/SkFloatBits.cpp
@@ -85,7 +85,16 @@
value = SkApplySign(value, SkExtractSign(packed));
exp = -exp;
if (exp > 25) { // underflow
+#ifdef SK_DISCARD_DENORMALIZED_FOR_SPEED
+ // The iOS ARM processor discards small denormalized numbers to go faster.
+ // The comparision below empirically causes the result to agree with the
+ // tests in MathTest test_float_floor
+ if (exp > 149) {
+ return 0;
+ }
+#else
exp = 25;
+#endif
}
// int add = 0;
return value >> exp;
@@ -145,7 +154,17 @@
value = SkApplySign(value, SkExtractSign(packed));
exp = -exp;
if (exp > 25) { // underflow
+#ifdef SK_DISCARD_DENORMALIZED_FOR_SPEED
+ // The iOS ARM processor discards small denormalized numbers to go faster.
+ // The comparision below empirically causes the result to agree with the
+ // tests in MathTest test_float_ceil
+ if (exp > 149) {
+ return 0;
+ }
+ return 0 < value;
+#else
exp = 25;
+#endif
}
int add = (1 << exp) - 1;
return (value + add) >> exp;
diff --git a/src/core/SkMathPriv.h b/src/core/SkMathPriv.h
index f93ab61..e997045 100644
--- a/src/core/SkMathPriv.h
+++ b/src/core/SkMathPriv.h
@@ -10,6 +10,12 @@
#include "SkMath.h"
+#ifdef SK_BUILD_FOR_IOS
+// The iOS ARM processor discards small denormalized numbers to go faster.
+// Algorithms that rely on denormalized numbers need alternative implementations.
+#define SK_DISCARD_DENORMALIZED_FOR_SPEED
+#endif
+
/** Returns -1 if n < 0, else returns 0
*/
#define SkExtractSign(n) ((int32_t)(n) >> 31)
diff --git a/src/core/SkPoint.cpp b/src/core/SkPoint.cpp
index 719ee54..8a6d056 100644
--- a/src/core/SkPoint.cpp
+++ b/src/core/SkPoint.cpp
@@ -7,6 +7,7 @@
*/
+#include "SkMathPriv.h"
#include "SkPoint.h"
void SkIPoint::rotateCW(SkIPoint* dst) const {
@@ -168,7 +169,17 @@
// divide by inf. and return (0,0) vector.
double xx = x;
double yy = y;
+ #ifdef SK_DISCARD_DENORMALIZED_FOR_SPEED
+ // The iOS ARM processor discards small denormalized numbers to go faster.
+ // Casting this to a float would cause the scale to go to zero. Keeping it
+ // as a double for the multiply keeps the scale non-zero.
+ double dscale = length / sqrt(xx * xx + yy * yy);
+ fX = x * dscale;
+ fY = y * dscale;
+ return true;
+ #else
scale = (float)(length / sqrt(xx * xx + yy * yy));
+ #endif
}
fX = x * scale;
fY = y * scale;