Add FPDFText_GetTextRenderMode() API

This allows deciding if FPDFPageObj_GetFillColor() or
FPDFPageObj_GetStrokeColor() should be used to get the effective color
of a text object.

Change-Id: Ic6e99a9eb8512b164756da8b5fcd8cd7771271ae
Reviewed-on: https://pdfium-review.googlesource.com/36750
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

5 files changed, 147 insertions, 0 deletions

diff --git a/fpdfsdk/fpdf_edit_embeddertest.cpp b/fpdfsdk/fpdf_edit_embeddertest.cpp
index 9464417da1..445b0cc6b9 100644
--- a/fpdfsdk/fpdf_edit_embeddertest.cpp
+++ b/fpdfsdk/fpdf_edit_embeddertest.cpp
@@ -1487,6 +1487,23 @@ TEST_F(FPDFEditEmbeddertest, AddStandardFontText) {
   FPDF_ClosePage(page);
 }
 
+TEST_F(FPDFEditEmbeddertest, TestGetTextRenderMode) {
+  EXPECT_TRUE(OpenDocument("text_render_mode.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+  ASSERT_EQ(2, FPDFPage_CountObjects(page));
+
+  ASSERT_EQ(-1, FPDFText_GetTextRenderMode(nullptr));
+
+  FPDF_PAGEOBJECT fill = FPDFPage_GetObject(page, 0);
+  ASSERT_EQ(FPDF_TEXTRENDERMODE_FILL, FPDFText_GetTextRenderMode(fill));
+
+  FPDF_PAGEOBJECT stroke = FPDFPage_GetObject(page, 1);
+  ASSERT_EQ(FPDF_TEXTRENDERMODE_STROKE, FPDFText_GetTextRenderMode(stroke));
+
+  UnloadPage(page);
+}
+
 // Tests adding text from standard font using FPDFText_LoadStandardFont.
 TEST_F(FPDFEditEmbeddertest, AddStandardFontText2) {
   // Start with a blank page
diff --git a/fpdfsdk/fpdf_edittext.cpp b/fpdfsdk/fpdf_edittext.cpp
index 3115e2a16e..c552d615e4 100644
--- a/fpdfsdk/fpdf_edittext.cpp
+++ b/fpdfsdk/fpdf_edittext.cpp
@@ -14,6 +14,7 @@
 #include "core/fpdfapi/font/cpdf_type1font.h"
 #include "core/fpdfapi/page/cpdf_docpagedata.h"
 #include "core/fpdfapi/page/cpdf_textobject.h"
+#include "core/fpdfapi/page/cpdf_textstate.h"
 #include "core/fpdfapi/parser/cpdf_array.h"
 #include "core/fpdfapi/parser/cpdf_dictionary.h"
 #include "core/fpdfapi/parser/cpdf_document.h"
@@ -27,6 +28,31 @@
 #include "fpdfsdk/cpdfsdk_helpers.h"
 #include "public/fpdf_edit.h"
 
+// These checks are here because core/ and public/ cannot depend on each other.
+static_assert(static_cast<int>(TextRenderingMode::MODE_FILL) ==
+                  FPDF_TEXTRENDERMODE_FILL,
+              "TextRenderingMode::MODE_FILL value mismatch");
+static_assert(static_cast<int>(TextRenderingMode::MODE_STROKE) ==
+                  FPDF_TEXTRENDERMODE_STROKE,
+              "TextRenderingMode::MODE_STROKE value mismatch");
+static_assert(static_cast<int>(TextRenderingMode::MODE_FILL_STROKE) ==
+                  FPDF_TEXTRENDERMODE_FILL_STROKE,
+              "TextRenderingMode::MODE_FILL_STROKE value mismatch");
+static_assert(static_cast<int>(TextRenderingMode::MODE_INVISIBLE) ==
+                  FPDF_TEXTRENDERMODE_INVISIBLE,
+              "TextRenderingMode::MODE_INVISIBLE value mismatch");
+static_assert(static_cast<int>(TextRenderingMode::MODE_FILL_CLIP) ==
+                  FPDF_TEXTRENDERMODE_FILL_CLIP,
+              "TextRenderingMode::MODE_FILL_CLIP value mismatch");
+static_assert(static_cast<int>(TextRenderingMode::MODE_STROKE_CLIP) ==
+                  FPDF_TEXTRENDERMODE_STROKE_CLIP,
+              "TextRenderingMode::MODE_STROKE_CLIP value mismatch");
+static_assert(static_cast<int>(TextRenderingMode::MODE_FILL_STROKE_CLIP) ==
+                  FPDF_TEXTRENDERMODE_FILL_STROKE_CLIP,
+              "TextRenderingMode::MODE_FILL_STROKE_CLIP value mismatch");
+static_assert(static_cast<int>(TextRenderingMode::MODE_CLIP) ==
+                  FPDF_TEXTRENDERMODE_CLIP,
+              "TextRenderingMode::MODE_CLIP value mismatch");
 namespace {
 
 CPDF_Dictionary* LoadFontDesc(CPDF_Document* pDoc,
@@ -545,3 +571,14 @@ FPDFPageObj_CreateTextObj(FPDF_DOCUMENT document,
   pTextObj->DefaultStates();
   return FPDFPageObjectFromCPDFPageObject(pTextObj.release());
 }
+
+FPDF_EXPORT int FPDF_CALLCONV FPDFText_GetTextRenderMode(FPDF_PAGEOBJECT text) {
+  if (!text)
+    return -1;
+
+  CPDF_TextObject* pTextObj = CPDFTextObjectFromFPDFPageObject(text);
+  if (!pTextObj)
+    return -1;
+
+  return static_cast<int>(pTextObj->m_TextState.GetTextMode());
+}
diff --git a/fpdfsdk/fpdf_view_c_api_test.c b/fpdfsdk/fpdf_view_c_api_test.c
index 997423a4a8..1837b58e2a 100644
--- a/fpdfsdk/fpdf_view_c_api_test.c
+++ b/fpdfsdk/fpdf_view_c_api_test.c
@@ -197,6 +197,7 @@ int CheckPDFiumCApi() {
     CHK(FPDFPath_SetStrokeWidth);
     CHK(FPDFTextObj_GetFontSize);
     CHK(FPDFText_GetMatrix);
+    CHK(FPDFText_GetTextRenderMode);
     CHK(FPDFText_LoadFont);
     CHK(FPDFText_LoadStandardFont);
     CHK(FPDFText_SetFillColor);
diff --git a/public/fpdf_edit.h b/public/fpdf_edit.h
index 6e613bca07..6490c18c6a 100644
--- a/public/fpdf_edit.h
+++ b/public/fpdf_edit.h
@@ -70,6 +70,15 @@
 #define FPDF_PRINTMODE_POSTSCRIPT2_PASSTHROUGH 4
 #define FPDF_PRINTMODE_POSTSCRIPT3_PASSTHROUGH 5
 
+#define FPDF_TEXTRENDERMODE_FILL 0
+#define FPDF_TEXTRENDERMODE_STROKE 1
+#define FPDF_TEXTRENDERMODE_FILL_STROKE 2
+#define FPDF_TEXTRENDERMODE_INVISIBLE 3
+#define FPDF_TEXTRENDERMODE_FILL_CLIP 4
+#define FPDF_TEXTRENDERMODE_STROKE_CLIP 5
+#define FPDF_TEXTRENDERMODE_FILL_STROKE_CLIP 6
+#define FPDF_TEXTRENDERMODE_CLIP 7
+
 typedef struct FPDF_IMAGEOBJ_METADATA {
   // The image width in pixels.
   unsigned int width;
@@ -1116,6 +1125,14 @@ FPDFPageObj_CreateTextObj(FPDF_DOCUMENT document,
                           FPDF_FONT font,
                           float font_size);
 
+// Experimental API.
+// Get the text rendering mode of a text object.
+//
+// text     - the handle to the text object.
+//
+// Returns one of the FPDF_TEXTRENDERMODE_* flags on success, -1 on error.
+FPDF_EXPORT int FPDF_CALLCONV FPDFText_GetTextRenderMode(FPDF_PAGEOBJECT text);
+
 #ifdef __cplusplus
 }  // extern "C"
 #endif  // __cplusplus
diff --git a/testing/resources/text_render_mode.pdf b/testing/resources/text_render_mode.pdf
new file mode 100644
index 0000000000..220e143757
--- /dev/null
+++ b/testing/resources/text_render_mode.pdf
@@ -0,0 +1,75 @@
+%PDF-1.2
+%âãÏÓ
+1 0 obj 
+<<
+/Resources 2 0 R
+/Contents 3 0 R
+/Parent 4 0 R
+/Type /Page
+/MediaBox [0 0 612 446]
+>>
+endobj 
+3 0 obj 
+<<
+/Length 102
+>>
+stream
+  BT
+  /F1 24 Tf
+  0 Tr
+  1 0 0 1 260 250 Tm
+  (fill)Tj
+  1 Tr
+  1 0 0 1 260 200 Tm
+  (stroke)Tj
+  ET
+
+endstream 
+endobj 
+2 0 obj 
+<<
+/Font 
+<<
+/F1 5 0 R
+>>
+>>
+endobj 
+5 0 obj 
+<<
+/Subtype /Type1
+/Name /F1
+/Type /Font
+/BaseFont /Helvetica
+>>
+endobj 
+4 0 obj 
+<<
+/Kids [1 0 R]
+/Type /Pages
+/MediaBox [0 0 612 446]
+/Count 1
+>>
+endobj 
+6 0 obj 
+<<
+/Type /Catalog
+/Pages 4 0 R
+>>
+endobj xref
+0 7
+0000000000 65535 f 
+0000000015 00000 n 
+0000000277 00000 n 
+0000000121 00000 n 
+0000000405 00000 n 
+0000000323 00000 n 
+0000000488 00000 n 
+trailer
+
+<<
+/Root 6 0 R
+/Size 7
+>>
+startxref
+538
+%%EOF