1 // Copyright 2016 The PDFium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6
7 #include "core/fpdfapi/render/cpdf_scaledrenderbuffer.h"
8
9 #include "core/fpdfapi/parser/cpdf_dictionary.h"
10 #include "core/fpdfapi/render/cpdf_devicebuffer.h"
11 #include "core/fpdfapi/render/cpdf_rendercontext.h"
12 #include "core/fxge/cfx_defaultrenderdevice.h"
13 #include "core/fxge/dib/cfx_dibitmap.h"
14
15 namespace {
16
17 constexpr size_t kImageSizeLimitBytes = 30 * 1024 * 1024;
18
19 } // namespace
20
21 CPDF_ScaledRenderBuffer::CPDF_ScaledRenderBuffer() = default;
22
23 CPDF_ScaledRenderBuffer::~CPDF_ScaledRenderBuffer() = default;
24
Initialize(CPDF_RenderContext * pContext,CFX_RenderDevice * pDevice,const FX_RECT & rect,const CPDF_PageObject * pObj,const CPDF_RenderOptions * pOptions,int max_dpi)25 bool CPDF_ScaledRenderBuffer::Initialize(CPDF_RenderContext* pContext,
26 CFX_RenderDevice* pDevice,
27 const FX_RECT& rect,
28 const CPDF_PageObject* pObj,
29 const CPDF_RenderOptions* pOptions,
30 int max_dpi) {
31 m_pDevice = pDevice;
32 if (m_pDevice->GetDeviceCaps(FXDC_RENDER_CAPS) & FXRC_GET_BITS)
33 return true;
34
35 m_Rect = rect;
36 m_Matrix = CPDF_DeviceBuffer::CalculateMatrix(pDevice, rect, max_dpi,
37 /*scale=*/true);
38 m_pBitmapDevice = std::make_unique<CFX_DefaultRenderDevice>();
39 bool bIsAlpha =
40 !!(m_pDevice->GetDeviceCaps(FXDC_RENDER_CAPS) & FXRC_ALPHA_OUTPUT);
41 FXDIB_Format dibFormat = bIsAlpha ? FXDIB_Format::kArgb : FXDIB_Format::kRgb;
42 while (true) {
43 FX_RECT bitmap_rect =
44 m_Matrix.TransformRect(CFX_FloatRect(rect)).GetOuterRect();
45 int32_t width = bitmap_rect.Width();
46 int32_t height = bitmap_rect.Height();
47 // Set to 0 to make CalculatePitchAndSize() calculate it.
48 constexpr uint32_t kNoPitch = 0;
49 absl::optional<CFX_DIBitmap::PitchAndSize> pitch_size =
50 CFX_DIBitmap::CalculatePitchAndSize(width, height, dibFormat, kNoPitch);
51 if (!pitch_size.has_value())
52 return false;
53
54 if (pitch_size.value().size <= kImageSizeLimitBytes &&
55 m_pBitmapDevice->Create(width, height, dibFormat, nullptr)) {
56 break;
57 }
58 m_Matrix.Scale(0.5f, 0.5f);
59 }
60 pContext->GetBackground(m_pBitmapDevice->GetBitmap(), pObj, pOptions,
61 m_Matrix);
62 return true;
63 }
64
GetDevice() const65 CFX_RenderDevice* CPDF_ScaledRenderBuffer::GetDevice() const {
66 return m_pBitmapDevice ? static_cast<CFX_RenderDevice*>(m_pBitmapDevice.get())
67 : m_pDevice.get();
68 }
69
OutputToDevice()70 void CPDF_ScaledRenderBuffer::OutputToDevice() {
71 if (m_pBitmapDevice) {
72 m_pDevice->StretchDIBits(m_pBitmapDevice->GetBitmap(), m_Rect.left,
73 m_Rect.top, m_Rect.Width(), m_Rect.Height());
74 }
75 }
76