tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
Log | Files | Refs | README | LICENSE

BufferUnrotate.cpp (2427B)

      1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
      2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
      3 /* This Source Code Form is subject to the terms of the Mozilla Public
      4 * License, v. 2.0. If a copy of the MPL was not distributed with this
      5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      6 
      7 #include "BufferUnrotate.h"
      8 
      9 #include <algorithm>  // min & max
     10 #include <stdint.h>
     11 #include <string.h>
     12 
     13 namespace mozilla {
     14 namespace gfx {
     15 
     16 void BufferUnrotate(uint8_t* aBuffer, int aByteWidth, int aHeight,
     17                    int aByteStride, int aXBoundary, int aYBoundary) {
     18  if (aXBoundary != 0) {
     19    uint8_t* line = new uint8_t[aByteWidth];
     20    uint32_t smallStart = 0;
     21    uint32_t smallLen = aXBoundary;
     22    uint32_t smallDest = aByteWidth - aXBoundary;
     23    uint32_t largeStart = aXBoundary;
     24    uint32_t largeLen = aByteWidth - aXBoundary;
     25    uint32_t largeDest = 0;
     26    if (aXBoundary > aByteWidth / 2) {
     27      smallStart = aXBoundary;
     28      smallLen = aByteWidth - aXBoundary;
     29      smallDest = 0;
     30      largeStart = 0;
     31      largeLen = aXBoundary;
     32      largeDest = smallLen;
     33    }
     34 
     35    for (int y = 0; y < aHeight; y++) {
     36      int yOffset = y * aByteStride;
     37      memcpy(line, &aBuffer[yOffset + smallStart], smallLen);
     38      memmove(&aBuffer[yOffset + largeDest], &aBuffer[yOffset + largeStart],
     39              largeLen);
     40      memcpy(&aBuffer[yOffset + smallDest], line, smallLen);
     41    }
     42 
     43    delete[] line;
     44  }
     45 
     46  if (aYBoundary != 0) {
     47    uint32_t smallestHeight = std::min(aHeight - aYBoundary, aYBoundary);
     48    uint32_t largestHeight = std::max(aHeight - aYBoundary, aYBoundary);
     49    uint32_t smallOffset = 0;
     50    uint32_t largeOffset = aYBoundary * aByteStride;
     51    uint32_t largeDestOffset = 0;
     52    uint32_t smallDestOffset = largestHeight * aByteStride;
     53    if (aYBoundary > aHeight / 2) {
     54      smallOffset = aYBoundary * aByteStride;
     55      largeOffset = 0;
     56      largeDestOffset = smallestHeight * aByteStride;
     57      smallDestOffset = 0;
     58    }
     59 
     60    uint8_t* smallestSide = new uint8_t[aByteStride * smallestHeight];
     61    memcpy(smallestSide, &aBuffer[smallOffset], aByteStride * smallestHeight);
     62    memmove(&aBuffer[largeDestOffset], &aBuffer[largeOffset],
     63            aByteStride * largestHeight);
     64    memcpy(&aBuffer[smallDestOffset], smallestSide,
     65           aByteStride * smallestHeight);
     66    delete[] smallestSide;
     67  }
     68 }
     69 
     70 }  // namespace gfx
     71 }  // namespace mozilla