1 files changed, 79 insertions, 0 deletions
diff --git a/core/fpdfapi/render/cpdf_scaledrenderbuffer.cpp b/core/fpdfapi/render/cpdf_scaledrenderbuffer.cpp
new file mode 100644
index 0000000000..a14bb9ea43
--- /dev/null
+++ b/core/fpdfapi/render/cpdf_scaledrenderbuffer.cpp
@@ -0,0 +1,79 @@
+// Copyright 2016 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 "core/fpdfapi/render/cpdf_scaledrenderbuffer.h"
+
+#include "core/fpdfapi/render/cpdf_rendercontext.h"
+#include "core/fpdfapi/render/cpdf_renderoptions.h"
+#include "core/fxge/cfx_fxgedevice.h"
+#include "core/fxge/cfx_renderdevice.h"
+
+#define _FPDFAPI_IMAGESIZE_LIMIT_ (30 * 1024 * 1024)
+
+CPDF_ScaledRenderBuffer::CPDF_ScaledRenderBuffer() {}
+
+CPDF_ScaledRenderBuffer::~CPDF_ScaledRenderBuffer() {}
+
+bool CPDF_ScaledRenderBuffer::Initialize(CPDF_RenderContext* pContext,
+                                         CFX_RenderDevice* pDevice,
+                                         const FX_RECT& pRect,
+                                         const CPDF_PageObject* pObj,
+                                         const CPDF_RenderOptions* pOptions,
+                                         int max_dpi) {
+  m_pDevice = pDevice;
+  if (m_pDevice->GetDeviceCaps(FXDC_RENDER_CAPS) & FXRC_GET_BITS)
+    return true;
+
+  m_pContext = pContext;
+  m_Rect = pRect;
+  m_pObject = pObj;
+  m_Matrix.TranslateI(-pRect.left, -pRect.top);
+  int horz_size = pDevice->GetDeviceCaps(FXDC_HORZ_SIZE);
+  int vert_size = pDevice->GetDeviceCaps(FXDC_VERT_SIZE);
+  if (horz_size && vert_size && max_dpi) {
+    int dpih =
+        pDevice->GetDeviceCaps(FXDC_PIXEL_WIDTH) * 254 / (horz_size * 10);
+    int dpiv =
+        pDevice->GetDeviceCaps(FXDC_PIXEL_HEIGHT) * 254 / (vert_size * 10);
+    if (dpih > max_dpi)
+      m_Matrix.Scale((FX_FLOAT)(max_dpi) / dpih, 1.0f);
+    if (dpiv > max_dpi)
+      m_Matrix.Scale(1.0f, (FX_FLOAT)(max_dpi) / (FX_FLOAT)dpiv);
+  }
+  m_pBitmapDevice.reset(new CFX_FxgeDevice);
+  FXDIB_Format dibFormat = FXDIB_Rgb;
+  int32_t bpp = 24;
+  if (m_pDevice->GetDeviceCaps(FXDC_RENDER_CAPS) & FXRC_ALPHA_OUTPUT) {
+    dibFormat = FXDIB_Argb;
+    bpp = 32;
+  }
+  while (1) {
+    CFX_FloatRect rect(pRect);
+    m_Matrix.TransformRect(rect);
+    FX_RECT bitmap_rect = rect.GetOuterRect();
+    int32_t iWidth = bitmap_rect.Width();
+    int32_t iHeight = bitmap_rect.Height();
+    int32_t iPitch = (iWidth * bpp + 31) / 32 * 4;
+    if (iWidth * iHeight < 1)
+      return false;
+
+    if (iPitch * iHeight <= _FPDFAPI_IMAGESIZE_LIMIT_ &&
+        m_pBitmapDevice->Create(iWidth, iHeight, dibFormat, nullptr)) {
+      break;
+    }
+    m_Matrix.Scale(0.5f, 0.5f);
+  }
+  m_pContext->GetBackground(m_pBitmapDevice->GetBitmap(), m_pObject, pOptions,
+                            &m_Matrix);
+  return true;
+}
+
+void CPDF_ScaledRenderBuffer::OutputToDevice() {
+  if (m_pBitmapDevice) {
+    m_pDevice->StretchDIBits(m_pBitmapDevice->GetBitmap(), m_Rect.left,
+                             m_Rect.top, m_Rect.Width(), m_Rect.Height());
+  }
+}