pdf/number_image_generator.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "pdf/number_image_generator.h"
   6
   7 #include "base/logging.h"
   8 #include "base/strings/string_util.h"
   9 #include "pdf/draw_utils.h"
  10 #include "pdf/instance.h"
  11
  12 namespace chrome_pdf {
  13
  14 const int kPageNumberSeparator = 0;
  15 const int kPageNumberOriginX = 8;
  16 const int kPageNumberOriginY = 4;
  17
  18 NumberImageGenerator::NumberImageGenerator(Instance* instance)
  19     : instance_(instance),
  20       device_scale_(1.0f) {
  21 }
  22
  23 NumberImageGenerator::~NumberImageGenerator() {
  24 }
  25
  26 void NumberImageGenerator::Configure(const pp::ImageData& number_background,
  27     const std::vector<pp::ImageData>& number_images, float device_scale) {
  28   number_background_ = number_background;
  29   number_images_ = number_images;
  30   device_scale_ = device_scale;
  31 }
  32
  33 void NumberImageGenerator::GenerateImage(
  34     int page_number, pp::ImageData* image) {
  35   char buffer[12];
  36   base::snprintf(buffer, sizeof(buffer), "%u", page_number);
  37   int extra_width = 0;
  38   DCHECK(number_images_.size() >= 10);
  39   DCHECK(!number_background_.is_null());
  40   for (size_t i = 1; i < strlen(buffer); ++i) {
  41     int index = buffer[i] - '0';
  42     extra_width += number_images_[index].size().width();
  43     extra_width += static_cast<int>(kPageNumberSeparator * device_scale_);
  44   }
  45
  46   *image = pp::ImageData(
  47       instance_,
  48       PP_IMAGEDATAFORMAT_BGRA_PREMUL,
  49       pp::Size(number_background_.size().width() + extra_width,
  50                number_background_.size().height()),
  51       false);
  52
  53   int stretch_point = number_background_.size().width() / 2;
  54
  55   pp::Rect src_rc(0, 0, stretch_point, number_background_.size().height());
  56   pp::Rect dest_rc(src_rc);
  57   CopyImage(number_background_, src_rc, image, dest_rc, false);
  58   src_rc.Offset(number_background_.size().width() - stretch_point, 0);
  59   dest_rc.Offset(image->size().width() - stretch_point, 0);
  60   CopyImage(number_background_, src_rc, image, dest_rc, false);
  61   src_rc = pp::Rect(stretch_point, 0, 1, number_background_.size().height());
  62   dest_rc = src_rc;
  63   dest_rc.set_width(extra_width + 1);
  64   CopyImage(number_background_, src_rc, image, dest_rc, true);
  65
  66   pp::Point origin(static_cast<int>(kPageNumberOriginX * device_scale_),
  67                    static_cast<int>(kPageNumberOriginY * device_scale_));
  68   for (size_t i = 0; i < strlen(buffer); ++i) {
  69     int index = buffer[i] - '0';
  70     CopyImage(
  71         number_images_[index],
  72         pp::Rect(pp::Point(), number_images_[index].size()),
  73         image, pp::Rect(origin, number_images_[index].size()), false);
  74     origin += pp::Point(
  75         number_images_[index].size().width() +
  76         static_cast<int>(kPageNumberSeparator * device_scale_), 0);
  77   }
  78 }
  79
  80 }  // namespace chrome_pdf
  81