reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame^] | 1 | /* libs/graphics/sgl/SkBlitter_A1.cpp |
| 2 | ** |
| 3 | ** Copyright 2006, The Android Open Source Project |
| 4 | ** |
| 5 | ** Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | ** you may not use this file except in compliance with the License. |
| 7 | ** You may obtain a copy of the License at |
| 8 | ** |
| 9 | ** http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | ** |
| 11 | ** Unless required by applicable law or agreed to in writing, software |
| 12 | ** distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | ** See the License for the specific language governing permissions and |
| 15 | ** limitations under the License. |
| 16 | */ |
| 17 | |
| 18 | #include "SkCoreBlitters.h" |
| 19 | |
| 20 | SkA1_Blitter::SkA1_Blitter(const SkBitmap& device, const SkPaint& paint) |
| 21 | : INHERITED(device) |
| 22 | { |
| 23 | fSrcA = SkToU8(SkColorGetA(paint.getColor())); |
| 24 | } |
| 25 | |
| 26 | void SkA1_Blitter::blitH(int x, int y, int width) |
| 27 | { |
| 28 | SkASSERT(x >= 0 && y >= 0 && (unsigned)(x + width) <= (unsigned)fDevice.width()); |
| 29 | |
| 30 | if (fSrcA <= 0x7F) |
| 31 | return; |
| 32 | |
| 33 | uint8_t* dst = fDevice.getAddr1(x, y); |
| 34 | int right = x + width; |
| 35 | |
| 36 | int left_mask = 0xFF >> (x & 7); |
| 37 | int rite_mask = 0xFF << (8 - (right & 7)); |
| 38 | int full_runs = (right >> 3) - ((x + 7) >> 3); |
| 39 | |
| 40 | // check for empty right mask, so we don't read off the end (or go slower than we need to) |
| 41 | if (rite_mask == 0) |
| 42 | { |
| 43 | SkASSERT(full_runs >= 0); |
| 44 | full_runs -= 1; |
| 45 | rite_mask = 0xFF; |
| 46 | } |
| 47 | if (left_mask == 0xFF) |
| 48 | full_runs -= 1; |
| 49 | |
| 50 | if (full_runs < 0) |
| 51 | { |
| 52 | SkASSERT((left_mask & rite_mask) != 0); |
| 53 | *dst |= (left_mask & rite_mask); |
| 54 | } |
| 55 | else |
| 56 | { |
| 57 | *dst++ |= left_mask; |
| 58 | memset(dst, 0xFF, full_runs); |
| 59 | dst += full_runs; |
| 60 | *dst |= rite_mask; |
| 61 | } |
| 62 | } |
| 63 | |