1a8e6aba48
Also remove the second, bespoke implementation in displacement map effect. Bug: skia: Change-Id: I7363673337caba73c1311fe3cef4385dd7d1804e Reviewed-on: https://skia-review.googlesource.com/c/167840 Commit-Queue: Brian Osman <brianosman@google.com> Commit-Queue: Mike Klein <mtklein@google.com> Auto-Submit: Brian Osman <brianosman@google.com> Reviewed-by: Mike Klein <mtklein@google.com>
57 lines
1.1 KiB
C++
57 lines
1.1 KiB
C++
|
|
/*
|
|
* Copyright 2008 The Android Open Source Project
|
|
*
|
|
* Use of this source code is governed by a BSD-style license that can be
|
|
* found in the LICENSE file.
|
|
*/
|
|
|
|
|
|
|
|
|
|
|
|
#ifndef SkUnPreMultiply_DEFINED
|
|
#define SkUnPreMultiply_DEFINED
|
|
|
|
#include "SkColor.h"
|
|
|
|
class SK_API SkUnPreMultiply {
|
|
public:
|
|
typedef uint32_t Scale;
|
|
|
|
// index this table with alpha [0..255]
|
|
static const Scale* GetScaleTable() {
|
|
return gTable;
|
|
}
|
|
|
|
static Scale GetScale(U8CPU alpha) {
|
|
SkASSERT(alpha <= 255);
|
|
return gTable[alpha];
|
|
}
|
|
|
|
/** Usage:
|
|
|
|
const Scale* table = SkUnPreMultiply::GetScaleTable();
|
|
|
|
for (...) {
|
|
unsigned a = ...
|
|
SkUnPreMultiply::Scale scale = table[a];
|
|
|
|
red = SkUnPreMultiply::ApplyScale(scale, red);
|
|
...
|
|
// now red is unpremultiplied
|
|
}
|
|
*/
|
|
static U8CPU ApplyScale(Scale scale, U8CPU component) {
|
|
SkASSERT(component <= 255);
|
|
return (scale * component + (1 << 23)) >> 24;
|
|
}
|
|
|
|
static SkColor PMColorToColor(SkPMColor c);
|
|
|
|
private:
|
|
static const uint32_t gTable[256];
|
|
};
|
|
|
|
#endif
|