Add the pdf plugin's source in src\pdf.

pdf/draw_utils.cc

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "pdf/draw_utils.h"
+
+#include <algorithm>
+#include <math.h>
+#include <vector>
+
+#include "base/logging.h"
+
+namespace chrome_pdf {
+
+inline uint8 GetBlue(const uint32& pixel) {
+  return static_cast<uint8>(pixel & 0xFF);
+}
+
+inline uint8 GetGreen(const uint32& pixel) {
+  return static_cast<uint8>((pixel >> 8) & 0xFF);
+}
+
+inline uint8 GetRed(const uint32& pixel) {
+  return static_cast<uint8>((pixel >> 16) & 0xFF);
+}
+
+inline uint8 GetAlpha(const uint32& pixel) {
+  return static_cast<uint8>((pixel >> 24) & 0xFF);
+}
+
+inline uint32_t MakePixel(uint8 red, uint8 green, uint8 blue, uint8 alpha) {
+  return (static_cast<uint32_t>(alpha) << 24) |
+      (static_cast<uint32_t>(red) << 16) |
+      (static_cast<uint32_t>(green) << 8) |
+      static_cast<uint32_t>(blue);
+}
+
+inline uint8 GradientChannel(uint8 start, uint8 end, double ratio) {
+  double new_channel = start - (static_cast<double>(start) - end) * ratio;
+  if (new_channel < 0)
+    return 0;
+  if (new_channel > 255)
+    return 255;
+  return static_cast<uint8>(new_channel + 0.5);
+}
+
+inline uint8 ProcessColor(uint8 src_color, uint8 dest_color, uint8 alpha) {
+  uint32 processed = static_cast<uint32>(src_color) * alpha +
+      static_cast<uint32>(dest_color) * (0xFF - alpha);
+  return static_cast<uint8>((processed / 0xFF) & 0xFF);
+}
+
+bool AlphaBlend(const pp::ImageData& src, const pp::Rect& src_rc,
+                pp::ImageData* dest, const pp::Point& dest_origin,
+                uint8 alpha_adjustment) {
+  const uint32_t* src_origin_pixel = src.GetAddr32(src_rc.point());
+  uint32_t* dest_origin_pixel = dest->GetAddr32(dest_origin);
+
+  int height = src_rc.height();
+  int width = src_rc.width();
+  for (int y = 0; y < height; y++) {
+    const uint32_t* src_pixel = src_origin_pixel;
+    uint32_t* dest_pixel = dest_origin_pixel;
+    for (int x = 0; x < width; x++) {
+      uint8 alpha = static_cast<uint8>(static_cast<uint32_t>(alpha_adjustment) *
+          GetAlpha(*src_pixel) / 0xFF);
+      uint8 red = ProcessColor(GetRed(*src_pixel), GetRed(*dest_pixel), alpha);
+      uint8 green = ProcessColor(GetGreen(*src_pixel),
+                                 GetGreen(*dest_pixel), alpha);
+      uint8 blue = ProcessColor(GetBlue(*src_pixel),
+                                GetBlue(*dest_pixel), alpha);
+      *dest_pixel = MakePixel(red, green, blue, GetAlpha(*dest_pixel));
+
+      src_pixel++;
+      dest_pixel++;
+    }
+    src_origin_pixel = reinterpret_cast<const uint32_t*>(
+        reinterpret_cast<const char*>(src_origin_pixel) + src.stride());
+    dest_origin_pixel = reinterpret_cast<uint32_t*>(
+        reinterpret_cast<char*>(dest_origin_pixel) + dest->stride());
+  }
+  return true;
+}
+
+void GradientFill(pp::ImageData* image, const pp::Rect& rc,
+                  uint32 start_color, uint32 end_color, bool horizontal) {
+  std::vector<uint32> colors;
+  colors.resize(horizontal ? rc.width() : rc.height());
+  for (size_t i = 0; i < colors.size(); ++i) {
+    double ratio = static_cast<double>(i) / colors.size();
+    colors[i] = MakePixel(
+        GradientChannel(GetRed(start_color), GetRed(end_color), ratio),
+        GradientChannel(GetGreen(start_color), GetGreen(end_color), ratio),
+        GradientChannel(GetBlue(start_color), GetBlue(end_color), ratio),
+        GradientChannel(GetAlpha(start_color), GetAlpha(end_color), ratio));
+  }
+
+  if (horizontal) {
+    const void* data = &(colors[0]);
+    size_t size = colors.size() * 4;
+    uint32_t* origin_pixel = image->GetAddr32(rc.point());
+    for (int y = 0; y < rc.height(); y++) {
+      memcpy(origin_pixel, data, size);
+      origin_pixel = reinterpret_cast<uint32_t*>(
+          reinterpret_cast<char*>(origin_pixel) + image->stride());
+    }
+  } else {
+    uint32_t* origin_pixel = image->GetAddr32(rc.point());
+    for (int y = 0; y < rc.height(); y++) {
+      uint32_t* pixel = origin_pixel;
+      for (int x = 0; x < rc.width(); x++) {
+        *pixel = colors[y];
+        pixel++;
+      }
+      origin_pixel = reinterpret_cast<uint32_t*>(
+          reinterpret_cast<char*>(origin_pixel) + image->stride());
+    }
+  }
+}
+
+void GradientFill(pp::Instance* instance,
+                  pp::ImageData* image,
+                  const pp::Rect& dirty_rc,
+                  const pp::Rect& gradient_rc,
+                  uint32 start_color,
+                  uint32 end_color,
+                  bool horizontal,
+                  uint8 transparency) {
+  pp::Rect draw_rc = gradient_rc.Intersect(dirty_rc);
+  if (draw_rc.IsEmpty())
+    return;
+
+  pp::ImageData gradient(instance, PP_IMAGEDATAFORMAT_BGRA_PREMUL,
+      gradient_rc.size(), false);
+
+  GradientFill(&gradient, pp::Rect(pp::Point(), gradient_rc.size()),
+               start_color, end_color, horizontal);
+
+  pp::Rect copy_rc(draw_rc);
+  copy_rc.Offset(-gradient_rc.x(), -gradient_rc.y());
+  AlphaBlend(gradient, copy_rc, image, draw_rc.point(), transparency);
+}
+
+void CopyImage(const pp::ImageData& src, const pp::Rect& src_rc,
+               pp::ImageData* dest, const pp::Rect& dest_rc,
+               bool stretch) {
+  DCHECK(src_rc.width() <= dest_rc.width() &&
+      src_rc.height() <= dest_rc.height());
+
+  const uint32_t* src_origin_pixel = src.GetAddr32(src_rc.point());
+  uint32_t* dest_origin_pixel = dest->GetAddr32(dest_rc.point());
+  if (stretch) {
+    double x_ratio = static_cast<double>(src_rc.width()) / dest_rc.width();
+    double y_ratio = static_cast<double>(src_rc.height()) / dest_rc.height();
+    int height = dest_rc.height();
+    int width = dest_rc.width();
+    for (int y = 0; y < height; y++) {
+      uint32_t* dest_pixel = dest_origin_pixel;
+      for (int x = 0; x < width; x++) {
+        uint32 src_x = static_cast<uint32>(x * x_ratio);
+        uint32 src_y = static_cast<uint32>(y * y_ratio);
+        const uint32_t* src_pixel = src.GetAddr32(
+            pp::Point(src_rc.x() + src_x, src_rc.y() + src_y));
+        *dest_pixel = *src_pixel;
+        dest_pixel++;
+      }
+      dest_origin_pixel = reinterpret_cast<uint32_t*>(
+          reinterpret_cast<char*>(dest_origin_pixel) + dest->stride());
+    }
+  } else {
+    int height = src_rc.height();
+    int width_bytes = src_rc.width() * 4;
+    for (int y = 0; y < height; y++) {
+      memcpy(dest_origin_pixel, src_origin_pixel, width_bytes);
+      src_origin_pixel = reinterpret_cast<const uint32_t*>(
+          reinterpret_cast<const char*>(src_origin_pixel) + src.stride());
+      dest_origin_pixel = reinterpret_cast<uint32_t*>(
+          reinterpret_cast<char*>(dest_origin_pixel) + dest->stride());
+    }
+  }
+}
+
+void FillRect(pp::ImageData* image, const pp::Rect& rc, uint32 color) {
+  int height = rc.height();
+  if (height == 0)
+    return;
+
+  // Fill in first row.
+  uint32_t* top_line = image->GetAddr32(rc.point());
+  int width = rc.width();
+  for (int x = 0; x < width; x++)
+    top_line[x] = color;
+
+  // Fill in the rest of the rectangle.
+  int byte_width = width * 4;
+  uint32_t* cur_line = reinterpret_cast<uint32_t*>(
+          reinterpret_cast<char*>(top_line) + image->stride());
+  for (int y = 1; y < height; y++) {
+    memcpy(cur_line, top_line, byte_width);
+    cur_line = reinterpret_cast<uint32_t*>(
+            reinterpret_cast<char*>(cur_line) + image->stride());
+  }
+}
+
+ShadowMatrix::ShadowMatrix(uint32 depth, double factor, uint32 background)
+    : depth_(depth), factor_(factor), background_(background) {
+  DCHECK(depth_ > 0);
+  matrix_.resize(depth_ * depth_);
+
+  // pv - is a rounding power factor for smoothing corners.
+  // pv = 2.0 will make corners completely round.
+  const double pv = 4.0;
+  // pow_pv - cache to avoid recalculating pow(x, pv) every time.
+  std::vector<double> pow_pv(depth_, 0.0);
+
+  double r = static_cast<double>(depth_);
+  double coef = 256.0 / pow(r, factor);
+
+  for (uint32 y = 0; y < depth_; y++) {
+    // Since matrix is symmetrical, we can reduce the number of calculations
+    // by mirroring results.
+    for (uint32 x = 0; x <= y; x++) {
+      // Fill cache if needed.
+      if (pow_pv[x] == 0.0)
+        pow_pv[x] =  pow(x, pv);
+      if (pow_pv[y] == 0.0)
+        pow_pv[y] =  pow(y, pv);
+
+      // v - is a value for the smoothing function.
+      // If x == 0 simplify calculations.
+      double v = (x == 0) ? y : pow(pow_pv[x] + pow_pv[y], 1 / pv);
+
+      // Smoothing function.
+      // If factor == 1, smoothing will be linear from 0 to the end,
+      // if 0 < factor < 1, smoothing will drop faster near 0.
+      // if factor > 1, smoothing will drop faster near the end (depth).
+      double f = 256.0 - coef * pow(v, factor);
+
+      uint8 alpha = 0;
+      if (f > kOpaqueAlpha)
+        alpha = kOpaqueAlpha;
+      else if (f < kTransparentAlpha)
+        alpha = kTransparentAlpha;
+      else
+        alpha = static_cast<uint8>(f);
+
+      uint8 red = ProcessColor(0, GetRed(background), alpha);
+      uint8 green = ProcessColor(0, GetGreen(background), alpha);
+      uint8 blue = ProcessColor(0, GetBlue(background), alpha);
+      uint32 pixel = MakePixel(red, green, blue, GetAlpha(background));
+
+      // Mirror matrix.
+      matrix_[y * depth_ + x] = pixel;
+      matrix_[x * depth_ + y] = pixel;
+    }
+  }
+}
+
+ShadowMatrix::~ShadowMatrix() {
+}
+
+void PaintShadow(pp::ImageData* image,
+                 const pp::Rect& clip_rc,
+                 const pp::Rect& shadow_rc,
+                 const ShadowMatrix& matrix) {
+  pp::Rect draw_rc = shadow_rc.Intersect(clip_rc);
+  if (draw_rc.IsEmpty())
+    return;
+
+  int32 depth = static_cast<int32>(matrix.depth());
+  for (int32_t y = draw_rc.y(); y < draw_rc.bottom(); y++) {
+    for (int32_t x = draw_rc.x(); x < draw_rc.right(); x++) {
+      int32_t matrix_x = std::max(depth + shadow_rc.x() - x - 1,
+                                  depth - shadow_rc.right() + x);
+      int32_t matrix_y = std::max(depth + shadow_rc.y() - y - 1,
+                                  depth - shadow_rc.bottom() + y);
+      uint32_t* pixel = image->GetAddr32(pp::Point(x, y));
+
+      if (matrix_x < 0)
+        matrix_x = 0;
+      else if (matrix_x >= static_cast<int32>(depth))
+        matrix_x = depth - 1;
+
+      if (matrix_y < 0)
+        matrix_y = 0;
+      else if (matrix_y >= static_cast<int32>(depth))
+        matrix_y = depth - 1;
+
+      *pixel = matrix.GetValue(matrix_x, matrix_y);
+    }
+  }
+}
+
+void DrawShadow(pp::ImageData* image,
+                const pp::Rect& shadow_rc,
+                const pp::Rect& object_rc,
+                const pp::Rect& clip_rc,
+                const ShadowMatrix& matrix) {
+  if (shadow_rc == object_rc)
+    return;  // Nothing to paint.
+
+  // Fill top part.
+  pp::Rect rc(shadow_rc.point(),
+              pp::Size(shadow_rc.width(), object_rc.y() - shadow_rc.y()));
+  PaintShadow(image, rc.Intersect(clip_rc), shadow_rc, matrix);
+
+  // Fill bottom part.
+  rc = pp::Rect(shadow_rc.x(), object_rc.bottom(),
+                shadow_rc.width(), shadow_rc.bottom() - object_rc.bottom());
+  PaintShadow(image, rc.Intersect(clip_rc), shadow_rc, matrix);
+
+  // Fill left part.
+  rc = pp::Rect(shadow_rc.x(), object_rc.y(),
+                object_rc.x() - shadow_rc.x(), object_rc.height());
+  PaintShadow(image, rc.Intersect(clip_rc), shadow_rc, matrix);
+
+  // Fill right part.
+  rc = pp::Rect(object_rc.right(), object_rc.y(),
+                shadow_rc.right() - object_rc.right(), object_rc.height());
+  PaintShadow(image, rc.Intersect(clip_rc), shadow_rc, matrix);
+}
+
+}  // namespace chrome_pdf
+