Add CPDF_Page::DeviceToPage() / PageToDevice().

Just like CPDFXFA_Page. Also mark the methods const.

Change-Id: I6717b4b61a29663780f45bf872f76fe8e671df75
Reviewed-on: https://pdfium-review.googlesource.com/30132
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

2 files changed, 38 insertions, 0 deletions

diff --git a/core/fpdfapi/page/cpdf_page.cpp b/core/fpdfapi/page/cpdf_page.cpp
index eb1f0b535d..06043ead35 100644
--- a/core/fpdfapi/page/cpdf_page.cpp
+++ b/core/fpdfapi/page/cpdf_page.cpp
@@ -118,6 +118,32 @@ CFX_FloatRect CPDF_Page::GetBox(const ByteString& name) const {
   return box;
 }
 
+void CPDF_Page::DeviceToPage(const FX_RECT& rect,
+                             int rotate,
+                             const CFX_PointF& device_point,
+                             double* page_x,
+                             double* page_y) const {
+  CFX_Matrix page2device = GetDisplayMatrix(rect, rotate);
+  CFX_PointF pos = page2device.GetInverse().Transform(device_point);
+
+  *page_x = pos.x;
+  *page_y = pos.y;
+}
+
+void CPDF_Page::PageToDevice(const FX_RECT& rect,
+                             int rotate,
+                             double page_x,
+                             double page_y,
+                             int* device_x,
+                             int* device_y) const {
+  CFX_Matrix page2device = GetDisplayMatrix(rect, rotate);
+  CFX_PointF pos = page2device.Transform(
+      CFX_PointF(static_cast<float>(page_x), static_cast<float>(page_y)));
+
+  *device_x = FXSYS_round(pos.x);
+  *device_y = FXSYS_round(pos.y);
+}
+
 CFX_Matrix CPDF_Page::GetDisplayMatrix(const FX_RECT& rect, int iRotate) const {
   if (m_PageSize.width == 0 || m_PageSize.height == 0)
     return CFX_Matrix();
diff --git a/core/fpdfapi/page/cpdf_page.h b/core/fpdfapi/page/cpdf_page.h
index 39c1b72c27..d199ea41db 100644
--- a/core/fpdfapi/page/cpdf_page.h
+++ b/core/fpdfapi/page/cpdf_page.h
@@ -33,6 +33,18 @@ class CPDF_Page : public CPDF_PageObjectHolder {
 
   void ParseContent();
 
+  void DeviceToPage(const FX_RECT& rect,
+                    int rotate,
+                    const CFX_PointF& device_point,
+                    double* page_x,
+                    double* page_y) const;
+  void PageToDevice(const FX_RECT& rect,
+                    int rotate,
+                    double page_x,
+                    double page_y,
+                    int* device_x,
+                    int* device_y) const;
+
   CFX_Matrix GetDisplayMatrix(const FX_RECT& rect, int iRotate) const;
 
   float GetPageWidth() const { return m_PageSize.width; }