gfx/2d/BufferUnrotate.cpp
author Brian Hackett <bhackett1024@gmail.com>
Thu, 27 Dec 2018 13:24:55 -1000
changeset 453697 e2af5f75beaf4ec851514352d62ff6f4b8a1d037
parent 448947 6f3709b3878117466168c40affa7bca0b60cf75b
child 460194 7183e211d4eb2faf52ca92391bf8809d13989a3f
permissions -rw-r--r--
Bug 1516578 Part 1 - Merge HitCheckpoint and HitBreakpoint messages, r=mccr8.

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include <algorithm>  // min & max
#include <cstdlib>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

namespace mozilla {
namespace gfx {

void BufferUnrotate(uint8_t* aBuffer, int aByteWidth, int aHeight,
                    int aByteStride, int aXBoundary, int aYBoundary) {
  if (aXBoundary != 0) {
    uint8_t* line = new uint8_t[aByteWidth];
    uint32_t smallStart = 0;
    uint32_t smallLen = aXBoundary;
    uint32_t smallDest = aByteWidth - aXBoundary;
    uint32_t largeStart = aXBoundary;
    uint32_t largeLen = aByteWidth - aXBoundary;
    uint32_t largeDest = 0;
    if (aXBoundary > aByteWidth / 2) {
      smallStart = aXBoundary;
      smallLen = aByteWidth - aXBoundary;
      smallDest = 0;
      largeStart = 0;
      largeLen = aXBoundary;
      largeDest = smallLen;
    }

    for (int y = 0; y < aHeight; y++) {
      int yOffset = y * aByteStride;
      memcpy(line, &aBuffer[yOffset + smallStart], smallLen);
      memmove(&aBuffer[yOffset + largeDest], &aBuffer[yOffset + largeStart],
              largeLen);
      memcpy(&aBuffer[yOffset + smallDest], line, smallLen);
    }

    delete[] line;
  }

  if (aYBoundary != 0) {
    uint32_t smallestHeight = std::min(aHeight - aYBoundary, aYBoundary);
    uint32_t largestHeight = std::max(aHeight - aYBoundary, aYBoundary);
    uint32_t smallOffset = 0;
    uint32_t largeOffset = aYBoundary * aByteStride;
    uint32_t largeDestOffset = 0;
    uint32_t smallDestOffset = largestHeight * aByteStride;
    if (aYBoundary > aHeight / 2) {
      smallOffset = aYBoundary * aByteStride;
      largeOffset = 0;
      largeDestOffset = smallestHeight * aByteStride;
      smallDestOffset = 0;
    }

    uint8_t* smallestSide = new uint8_t[aByteStride * smallestHeight];
    memcpy(smallestSide, &aBuffer[smallOffset], aByteStride * smallestHeight);
    memmove(&aBuffer[largeDestOffset], &aBuffer[largeOffset],
            aByteStride * largestHeight);
    memcpy(&aBuffer[smallDestOffset], smallestSide,
           aByteStride * smallestHeight);
    delete[] smallestSide;
  }
}

}  // namespace gfx
}  // namespace mozilla