| /* |
| * Copyright 2007 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. |
| */ |
| |
| #include "SkMask.h" |
| |
| #include "SkMalloc.h" |
| |
| //#define TRACK_SKMASK_LIFETIME |
| |
| /** returns the product if it is positive and fits in 31 bits. Otherwise this |
| returns 0. |
| */ |
| static int32_t safeMul32(int32_t a, int32_t b) { |
| int64_t size = sk_64_mul(a, b); |
| if (size > 0 && sk_64_isS32(size)) { |
| return sk_64_asS32(size); |
| } |
| return 0; |
| } |
| |
| size_t SkMask::computeImageSize() const { |
| return safeMul32(fBounds.height(), fRowBytes); |
| } |
| |
| size_t SkMask::computeTotalImageSize() const { |
| size_t size = this->computeImageSize(); |
| if (fFormat == SkMask::k3D_Format) { |
| size = safeMul32(SkToS32(size), 3); |
| } |
| return size; |
| } |
| |
| #ifdef TRACK_SKMASK_LIFETIME |
| static int gCounter; |
| #endif |
| |
| /** We explicitly use this allocator for SkBimap pixels, so that we can |
| freely assign memory allocated by one class to the other. |
| */ |
| uint8_t* SkMask::AllocImage(size_t size) { |
| #ifdef TRACK_SKMASK_LIFETIME |
| SkDebugf("SkMask::AllocImage %d\n", gCounter++); |
| #endif |
| return (uint8_t*)sk_malloc_throw(SkAlign4(size)); |
| } |
| |
| /** We explicitly use this allocator for SkBimap pixels, so that we can |
| freely assign memory allocated by one class to the other. |
| */ |
| void SkMask::FreeImage(void* image) { |
| #ifdef TRACK_SKMASK_LIFETIME |
| if (image) { |
| SkDebugf("SkMask::FreeImage %d\n", --gCounter); |
| } |
| #endif |
| sk_free(image); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| static const int gMaskFormatToShift[] = { |
| ~0, // BW -- not supported |
| 0, // A8 |
| 0, // 3D |
| 2, // ARGB32 |
| 1, // LCD16 |
| }; |
| |
| static int maskFormatToShift(SkMask::Format format) { |
| SkASSERT((unsigned)format < SK_ARRAY_COUNT(gMaskFormatToShift)); |
| SkASSERT(SkMask::kBW_Format != format); |
| return gMaskFormatToShift[format]; |
| } |
| |
| void* SkMask::getAddr(int x, int y) const { |
| SkASSERT(kBW_Format != fFormat); |
| SkASSERT(fBounds.contains(x, y)); |
| SkASSERT(fImage); |
| |
| char* addr = (char*)fImage; |
| addr += (y - fBounds.fTop) * fRowBytes; |
| addr += (x - fBounds.fLeft) << maskFormatToShift(fFormat); |
| return addr; |
| } |