Tidy up shading patterns

core/src/fpdfapi/fpdf_render/fpdf_render_image.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "render_int.h"
 
 #include <utility>
 #include <vector>
@@ skipping 504 matching lines @@
     return TRUE;
   }
   bitmap_device1.GetBitmap()->Clear(0xffffff);
   {
     CPDF_RenderStatus bitmap_render;
     bitmap_render.Initialize(m_pRenderStatus->m_pContext, &bitmap_device1, NULL,
                              NULL, NULL, NULL, &m_pRenderStatus->m_Options, 0,
                              m_pRenderStatus->m_bDropObjects, NULL, TRUE);
     CFX_Matrix patternDevice = *pObj2Device;
     patternDevice.Translate((FX_FLOAT)-rect.left, (FX_FLOAT)-rect.top);
-    if (m_pPattern->m_PatternType == PATTERN_TILING) {
-      bitmap_render.DrawTilingPattern((CPDF_TilingPattern*)m_pPattern,
-                                      m_pImageObject, &patternDevice, FALSE);
+    if (m_pPattern->m_PatternType == CPDF_Pattern::TILING) {
+      bitmap_render.DrawTilingPattern(
+          static_cast<CPDF_TilingPattern*>(m_pPattern), m_pImageObject,
+          &patternDevice, FALSE);
     } else {
-      bitmap_render.DrawShadingPattern((CPDF_ShadingPattern*)m_pPattern,
-                                       m_pImageObject, &patternDevice, FALSE);
+      bitmap_render.DrawShadingPattern(
+          static_cast<CPDF_ShadingPattern*>(m_pPattern), m_pImageObject,
+          &patternDevice, FALSE);
     }
   }
   {
     CFX_FxgeDevice bitmap_device2;
     if (!bitmap_device2.Create(rect.Width(), rect.Height(), FXDIB_8bppRgb)) {
       return TRUE;
     }
     bitmap_device2.GetBitmap()->Clear(0);
     CPDF_RenderStatus bitmap_render;
     bitmap_render.Initialize(m_pRenderStatus->m_pContext, &bitmap_device2, NULL,
@@ skipping 441 matching lines @@
   } else if (pFunc) {
     int size = dest_pitch * height;
     for (int i = 0; i < size; i++) {
       dest_buf[i] = transfers[src_buf[i]];
     }
   } else {
     FXSYS_memcpy(dest_buf, src_buf, dest_pitch * height);
   }
   return pMask.release();
 }