Convert some PDF transform code to use gfx::SizeF.

Now that PDFium has APIs to return float values, use them in conjunction
with gfx::SizeF to simplify CalculateScaleFactor() and related code.

Change-Id: I8d8e96c05db5eb6225e9f0a332b69706fa5a2d5d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1954770
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Cr-Commit-Position: refs/heads/master@{#723589}

pdf/pdf_transform.cc

@@ -8,7 +8,9 @@
 #include <utility>
 
 #include "base/logging.h"
+#include "ui/gfx/geometry/point_f.h"
 #include "ui/gfx/geometry/rect.h"
+#include "ui/gfx/geometry/size_f.h"
 
 namespace chrome_pdf {
 
@@ -25,19 +27,18 @@ void SwapPdfRectangleValuesIfNeeded(PdfRectangle* rect) {
 
 }  // namespace
 
-double CalculateScaleFactor(const gfx::Rect& content_rect,
-                            double src_width,
-                            double src_height,
+float CalculateScaleFactor(const gfx::Rect& content_rect,
+                           const gfx::SizeF& src_size,
                            bool rotated) {
-  if (src_width == 0 || src_height == 0)
-    return 1.0;
-
-  double actual_source_page_width = rotated ? src_height : src_width;
-  double actual_source_page_height = rotated ? src_width : src_height;
-  double ratio_x =
-      static_cast<double>(content_rect.width()) / actual_source_page_width;
-  double ratio_y =
-      static_cast<double>(content_rect.height()) / actual_source_page_height;
+  if (src_size.IsEmpty())
+    return 1.0f;
+
+  float actual_source_page_width =
+      rotated ? src_size.height() : src_size.width();
+  float actual_source_page_height =
+      rotated ? src_size.width() : src_size.height();
+  float ratio_x = content_rect.width() / actual_source_page_width;
+  float ratio_y = content_rect.height() / actual_source_page_height;
   return std::min(ratio_x, ratio_y);
 }
 
@@ -84,54 +85,45 @@ PdfRectangle CalculateClipBoxBoundary(const PdfRectangle& media_box,
   return clip_box;
 }
 
-void ScalePdfRectangle(double scale_factor, PdfRectangle* rect) {
+void ScalePdfRectangle(float scale_factor, PdfRectangle* rect) {
   rect->left *= scale_factor;
   rect->bottom *= scale_factor;
   rect->right *= scale_factor;
   rect->top *= scale_factor;
 }
 
-void CalculateScaledClipBoxOffset(const gfx::Rect& content_rect,
-                                  const PdfRectangle& source_clip_box,
-                                  double* offset_x,
-                                  double* offset_y) {
+gfx::PointF CalculateScaledClipBoxOffset(const gfx::Rect& content_rect,
+                                         const PdfRectangle& source_clip_box) {
   const float clip_box_width = source_clip_box.right - source_clip_box.left;
   const float clip_box_height = source_clip_box.top - source_clip_box.bottom;
 
   // Center the intended clip region to real clip region.
-  *offset_x = (content_rect.width() - clip_box_width) / 2 + content_rect.x() -
-              source_clip_box.left;
-  *offset_y = (content_rect.height() - clip_box_height) / 2 + content_rect.y() -
-              source_clip_box.bottom;
+  return gfx::PointF((content_rect.width() - clip_box_width) / 2 +
+                         content_rect.x() - source_clip_box.left,
+                     (content_rect.height() - clip_box_height) / 2 +
+                         content_rect.y() - source_clip_box.bottom);
 }
 
-void CalculateNonScaledClipBoxOffset(int rotation,
+gfx::PointF CalculateNonScaledClipBoxOffset(
+    int rotation,
     int page_width,
     int page_height,
-                                     const PdfRectangle& source_clip_box,
-                                     double* offset_x,
-                                     double* offset_y) {
+    const PdfRectangle& source_clip_box) {
   // Align the intended clip region to left-top corner of real clip region.
   switch (rotation) {
     case 0:
-      *offset_x = -1 * source_clip_box.left;
-      *offset_y = page_height - source_clip_box.top;
-      break;
+      return gfx::PointF(-1 * source_clip_box.left,
+                         page_height - source_clip_box.top);
     case 1:
-      *offset_x = 0;
-      *offset_y = -1 * source_clip_box.bottom;
-      break;
+      return gfx::PointF(0, -1 * source_clip_box.bottom);
     case 2:
-      *offset_x = page_width - source_clip_box.right;
-      *offset_y = 0;
-      break;
+      return gfx::PointF(page_width - source_clip_box.right, 0);
     case 3:
-      *offset_x = page_height - source_clip_box.right;
-      *offset_y = page_width - source_clip_box.top;
-      break;
+      return gfx::PointF(page_height - source_clip_box.right,
+                         page_width - source_clip_box.top);
     default:
       NOTREACHED();
-      break;
+      return gfx::PointF();
   }
 }
 

pdf/pdf_transform.h

@@ -6,7 +6,9 @@
 #define PDF_PDF_TRANSFORM_H_
 
 namespace gfx {
+class PointF;
 class Rect;
+class SizeF;
 }
 
 namespace chrome_pdf {
@@ -20,17 +22,14 @@ struct PdfRectangle {
   float top;
 };
 
-// Calculate the scale factor between |content_rect| and a page of size
-// |src_width| x |src_height|.
+// Calculate the scale factor between |content_rect| and a page of |src_size|.
 //
 // |content_rect| specifies the printable area of the destination page, with
 // origin at left-bottom. Values are in points.
-// |src_width| specifies the source page width in points.
-// |src_height| specifies the source page height in points.
+// |src_size| specifies the source page size in points.
 // |rotated| True if source page is rotated 90 degree or 270 degree.
-double CalculateScaleFactor(const gfx::Rect& content_rect,
-                            double src_width,
-                            double src_height,
+float CalculateScaleFactor(const gfx::Rect& content_rect,
+                           const gfx::SizeF& src_size,
                            bool rotated);
 
 // Make the default size to be letter size (8.5" X 11"). We are just following
@@ -58,7 +57,7 @@ PdfRectangle CalculateClipBoxBoundary(const PdfRectangle& media_box,
                                       const PdfRectangle& crop_box);
 
 // Scale |rect| by |scale_factor|.
-void ScalePdfRectangle(double scale_factor, PdfRectangle* rect);
+void ScalePdfRectangle(float scale_factor, PdfRectangle* rect);
 
 // Calculate the clip box translation offset for a page that does need to be
 // scaled. All parameters are in points.
@@ -67,12 +66,10 @@ void ScalePdfRectangle(double scale_factor, PdfRectangle* rect);
 // origin at left-bottom.
 // |source_clip_box| specifies the source clip box positions, relative to
 // origin at left-bottom.
-// |offset_x| and |offset_y| will contain the final translation offsets for the
-// source clip box, relative to origin at left-bottom.
-void CalculateScaledClipBoxOffset(const gfx::Rect& content_rect,
-                                  const PdfRectangle& source_clip_box,
-                                  double* offset_x,
-                                  double* offset_y);
+// Returns the final translation offsets for the source clip box, relative to
+// origin at left-bottom.
+gfx::PointF CalculateScaledClipBoxOffset(const gfx::Rect& content_rect,
+                                         const PdfRectangle& source_clip_box_);
 
 // Calculate the clip box offset for a page that does not need to be scaled.
 // All parameters are in points.
@@ -83,14 +80,13 @@ void CalculateScaledClipBoxOffset(const gfx::Rect& content_rect,
 // |page_height| specifies the screen destination page height.
 // |source_clip_box| specifies the source clip box positions, relative to origin
 // at left-bottom.
-// |offset_x| and |offset_y| will contain the final translation offsets for the
-// source clip box, relative to origin at left-bottom.
-void CalculateNonScaledClipBoxOffset(int rotation,
+// Returns the final translation offsets for the source clip box, relative to
+// origin at left-bottom.
+gfx::PointF CalculateNonScaledClipBoxOffset(
+    int rotation,
     int page_width,
     int page_height,
-                                     const PdfRectangle& source_clip_box,
-                                     double* offset_x,
-                                     double* offset_y);
+    const PdfRectangle& source_clip_box);
 
 }  // namespace chrome_pdf
 

pdf/pdfium/pdfium_print.cc

@@ -22,8 +22,10 @@
 #include "third_party/pdfium/public/fpdf_ppo.h"
 #include "third_party/pdfium/public/fpdf_transformpage.h"
 #include "ui/gfx/codec/jpeg_codec.h"
+#include "ui/gfx/geometry/point_f.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/size.h"
+#include "ui/gfx/geometry/size_f.h"
 
 using printing::ConvertUnit;
 using printing::ConvertUnitDouble;
@@ -69,17 +71,17 @@ void SetPageSizeAndContentRect(bool rotated,
 
 // Transform |page| contents to fit in the selected printer paper size.
 void TransformPDFPageForPrinting(FPDF_PAGE page,
-                                 double scale_factor,
+                                 float scale_factor,
                                  const PP_PrintSettings_Dev& print_settings) {
   // Get the source page width and height in points.
-  const double src_page_width = FPDF_GetPageWidth(page);
-  const double src_page_height = FPDF_GetPageHeight(page);
+  gfx::SizeF src_page_size(FPDF_GetPageWidthF(page), FPDF_GetPageHeightF(page));
   const int src_page_rotation = FPDFPage_GetRotation(page);
 
   pp::Size page_size(print_settings.paper_size);
   pp::Rect content_rect(print_settings.printable_area);
   const bool rotated = (src_page_rotation % 2 == 1);
-  SetPageSizeAndContentRect(rotated, src_page_width > src_page_height,
+  SetPageSizeAndContentRect(rotated,
+                            src_page_size.width() > src_page_size.height(),
                             &page_size, &content_rect);
 
   // Compute the screen page width and height in points.
@@ -106,8 +108,8 @@ void TransformPDFPageForPrinting(FPDF_PAGE page,
   }
 
   if (fitted_scaling) {
-    scale_factor = CalculateScaleFactor(gfx_printed_rect, src_page_width,
-                                        src_page_height, rotated);
+    scale_factor =
+        CalculateScaleFactor(gfx_printed_rect, src_page_size, rotated);
   }
 
   // Calculate positions for the clip box.
@@ -124,17 +126,12 @@ void TransformPDFPageForPrinting(FPDF_PAGE page,
   ScalePdfRectangle(scale_factor, &source_clip_box);
 
   // Calculate the translation offset values.
-  double offset_x = 0;
-  double offset_y = 0;
-
-  if (fitted_scaling) {
-    CalculateScaledClipBoxOffset(gfx_printed_rect, source_clip_box, &offset_x,
-                                 &offset_y);
-  } else {
-    CalculateNonScaledClipBoxOffset(src_page_rotation, actual_page_width,
-                                    actual_page_height, source_clip_box,
-                                    &offset_x, &offset_y);
-  }
+  gfx::PointF offset =
+      fitted_scaling
+          ? CalculateScaledClipBoxOffset(gfx_printed_rect, source_clip_box)
+          : CalculateNonScaledClipBoxOffset(
+                src_page_rotation, actual_page_width, actual_page_height,
+                source_clip_box);
 
   // Reset the media box and crop box. When the page has crop box and media box,
   // the plugin will display the crop box contents and not the entire media box.
@@ -148,28 +145,23 @@ void TransformPDFPageForPrinting(FPDF_PAGE page,
   // Transformation is not required, return. Do this check only after updating
   // the media box and crop box. For more detailed information, please refer to
   // the comment block right before FPDF_SetMediaBox and FPDF_GetMediaBox calls.
-  if (scale_factor == 1.0 && offset_x == 0 && offset_y == 0)
+  if (scale_factor == 1.0f && offset.IsOrigin())
     return;
 
   // All the positions have been calculated, now manipulate the PDF.
-  FS_MATRIX matrix = {static_cast<float>(scale_factor),
-                      0,
-                      0,
-                      static_cast<float>(scale_factor),
-                      static_cast<float>(offset_x),
-                      static_cast<float>(offset_y)};
-  FS_RECTF cliprect = {static_cast<float>(source_clip_box.left + offset_x),
-                       static_cast<float>(source_clip_box.top + offset_y),
-                       static_cast<float>(source_clip_box.right + offset_x),
-                       static_cast<float>(source_clip_box.bottom + offset_y)};
+  const FS_MATRIX matrix = {scale_factor, 0.0f,       0.0f,
+                            scale_factor, offset.x(), offset.y()};
+  const FS_RECTF cliprect = {
+      source_clip_box.left + offset.x(), source_clip_box.top + offset.y(),
+      source_clip_box.right + offset.x(), source_clip_box.bottom + offset.y()};
   FPDFPage_TransFormWithClip(page, &matrix, &cliprect);
-  FPDFPage_TransformAnnots(page, scale_factor, 0, 0, scale_factor, offset_x,
-                           offset_y);
+  FPDFPage_TransformAnnots(page, scale_factor, 0, 0, scale_factor, offset.x(),
+                           offset.y());
 }
 
 void FitContentsToPrintableAreaIfRequired(
     FPDF_DOCUMENT doc,
-    double scale_factor,
+    float scale_factor,
     const PP_PrintSettings_Dev& print_settings) {
   // Check to see if we need to fit pdf contents to printer paper size.
   if (print_settings.print_scaling_option == PP_PRINTSCALINGOPTION_SOURCE_SIZE)
@@ -334,7 +326,7 @@ void PDFiumPrint::FitContentsToPrintableArea(FPDF_DOCUMENT doc,
                printable_area.height());
   print_settings.print_scaling_option =
       PP_PRINTSCALINGOPTION_FIT_TO_PRINTABLE_AREA;
-  FitContentsToPrintableAreaIfRequired(doc, 1.0, print_settings);
+  FitContentsToPrintableAreaIfRequired(doc, 1.0f, print_settings);
 }
 
 std::vector<uint8_t> PDFiumPrint::PrintPagesAsPdf(
@@ -369,7 +361,7 @@ ScopedFPDFDocument PDFiumPrint::CreatePrintPdf(
     return nullptr;
   }
 
-  double scale_factor = pdf_print_settings.scale_factor / 100.0;
+  float scale_factor = pdf_print_settings.scale_factor / 100.0f;
   FitContentsToPrintableAreaIfRequired(output_doc.get(), scale_factor,
                                        print_settings);
   if (!FlattenPrintData(output_doc.get()))