| // 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/page/cpdf_shadingpattern.h" |
| |
| #include <algorithm> |
| |
| #include "core/fpdfapi/page/cpdf_docpagedata.h" |
| #include "core/fpdfapi/page/cpdf_function.h" |
| #include "core/fpdfapi/parser/cpdf_array.h" |
| #include "core/fpdfapi/parser/cpdf_dictionary.h" |
| #include "core/fpdfapi/parser/cpdf_document.h" |
| #include "core/fpdfapi/parser/cpdf_object.h" |
| #include "core/fpdfapi/parser/cpdf_stream.h" |
| #include "core/fxcrt/fx_safe_types.h" |
| #include "third_party/base/notreached.h" |
| |
| namespace { |
| |
| ShadingType ToShadingType(int type) { |
| return (type > kInvalidShading && type < kMaxShading) |
| ? static_cast<ShadingType>(type) |
| : kInvalidShading; |
| } |
| |
| } // namespace |
| |
| CPDF_ShadingPattern::CPDF_ShadingPattern(CPDF_Document* pDoc, |
| CPDF_Object* pPatternObj, |
| bool bShading, |
| const CFX_Matrix& parentMatrix) |
| : CPDF_Pattern(pDoc, pPatternObj, parentMatrix), m_bShading(bShading) { |
| ASSERT(document()); |
| if (!bShading) |
| SetPatternToFormMatrix(); |
| } |
| |
| CPDF_ShadingPattern::~CPDF_ShadingPattern() = default; |
| |
| CPDF_ShadingPattern* CPDF_ShadingPattern::AsShadingPattern() { |
| return this; |
| } |
| |
| bool CPDF_ShadingPattern::Load() { |
| if (m_ShadingType != kInvalidShading) |
| return true; |
| |
| const CPDF_Object* pShadingObj = GetShadingObject(); |
| const CPDF_Dictionary* pShadingDict = |
| pShadingObj ? pShadingObj->GetDict() : nullptr; |
| if (!pShadingDict) |
| return false; |
| |
| m_pFunctions.clear(); |
| const CPDF_Object* pFunc = pShadingDict->GetDirectObjectFor("Function"); |
| if (pFunc) { |
| if (const CPDF_Array* pArray = pFunc->AsArray()) { |
| m_pFunctions.resize(std::min<size_t>(pArray->size(), 4)); |
| for (size_t i = 0; i < m_pFunctions.size(); ++i) |
| m_pFunctions[i] = CPDF_Function::Load(pArray->GetDirectObjectAt(i)); |
| } else { |
| m_pFunctions.push_back(CPDF_Function::Load(pFunc)); |
| } |
| } |
| const CPDF_Object* pCSObj = pShadingDict->GetDirectObjectFor("ColorSpace"); |
| if (!pCSObj) |
| return false; |
| |
| auto* pDocPageData = CPDF_DocPageData::FromDocument(document()); |
| m_pCS = pDocPageData->GetColorSpace(pCSObj, nullptr); |
| |
| // The color space is required and cannot be a Pattern space, according to the |
| // PDF 1.7 spec, page 305. |
| if (!m_pCS || m_pCS->GetFamily() == PDFCS_PATTERN) |
| return false; |
| |
| m_ShadingType = ToShadingType(pShadingDict->GetIntegerFor("ShadingType")); |
| return Validate(); |
| } |
| |
| const CPDF_Object* CPDF_ShadingPattern::GetShadingObject() const { |
| return m_bShading ? pattern_obj() |
| : pattern_obj()->GetDict()->GetDirectObjectFor("Shading"); |
| } |
| |
| bool CPDF_ShadingPattern::Validate() const { |
| if (m_ShadingType == kInvalidShading) |
| return false; |
| |
| // We expect to have a stream if our shading type is a mesh. |
| if (IsMeshShading() && !ToStream(GetShadingObject())) |
| return false; |
| |
| // Validate color space |
| switch (m_ShadingType) { |
| case kFunctionBasedShading: |
| case kAxialShading: |
| case kRadialShading: { |
| if (m_pCS->GetFamily() == PDFCS_INDEXED) |
| return false; |
| break; |
| } |
| case kFreeFormGouraudTriangleMeshShading: |
| case kLatticeFormGouraudTriangleMeshShading: |
| case kCoonsPatchMeshShading: |
| case kTensorProductPatchMeshShading: { |
| if (!m_pFunctions.empty() && m_pCS->GetFamily() == PDFCS_INDEXED) |
| return false; |
| break; |
| } |
| default: { |
| NOTREACHED(); |
| return false; |
| } |
| } |
| |
| uint32_t nNumColorSpaceComponents = m_pCS->CountComponents(); |
| switch (m_ShadingType) { |
| case kFunctionBasedShading: { |
| // Either one 2-to-N function or N 2-to-1 functions. |
| return ValidateFunctions(1, 2, nNumColorSpaceComponents) || |
| ValidateFunctions(nNumColorSpaceComponents, 2, 1); |
| } |
| case kAxialShading: |
| case kRadialShading: { |
| // Either one 1-to-N function or N 1-to-1 functions. |
| return ValidateFunctions(1, 1, nNumColorSpaceComponents) || |
| ValidateFunctions(nNumColorSpaceComponents, 1, 1); |
| } |
| case kFreeFormGouraudTriangleMeshShading: |
| case kLatticeFormGouraudTriangleMeshShading: |
| case kCoonsPatchMeshShading: |
| case kTensorProductPatchMeshShading: { |
| // Either no function, one 1-to-N function, or N 1-to-1 functions. |
| return m_pFunctions.empty() || |
| ValidateFunctions(1, 1, nNumColorSpaceComponents) || |
| ValidateFunctions(nNumColorSpaceComponents, 1, 1); |
| } |
| default: |
| break; |
| } |
| NOTREACHED(); |
| return false; |
| } |
| |
| bool CPDF_ShadingPattern::ValidateFunctions( |
| uint32_t nExpectedNumFunctions, |
| uint32_t nExpectedNumInputs, |
| uint32_t nExpectedNumOutputs) const { |
| if (m_pFunctions.size() != nExpectedNumFunctions) |
| return false; |
| |
| FX_SAFE_UINT32 nTotalOutputs = 0; |
| for (const auto& function : m_pFunctions) { |
| if (!function) |
| return false; |
| |
| if (function->CountInputs() != nExpectedNumInputs || |
| function->CountOutputs() != nExpectedNumOutputs) { |
| return false; |
| } |
| |
| nTotalOutputs += function->CountOutputs(); |
| } |
| |
| return nTotalOutputs.IsValid(); |
| } |