1 files changed, 142 insertions, 0 deletions
diff --git a/gfx/skia/skia/src/pdf/SkPDFGraphicState.cpp b/gfx/skia/skia/src/pdf/SkPDFGraphicState.cpp
new file mode 100644
index 0000000000..6cab7441a6
--- /dev/null
+++ b/gfx/skia/skia/src/pdf/SkPDFGraphicState.cpp
@@ -0,0 +1,142 @@
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "src/pdf/SkPDFGraphicState.h"
+
+#include "include/core/SkData.h"
+#include "include/core/SkPaint.h"
+#include "include/docs/SkPDFDocument.h"
+#include "include/private/base/SkTo.h"
+#include "src/pdf/SkPDFDocumentPriv.h"
+#include "src/pdf/SkPDFFormXObject.h"
+#include "src/pdf/SkPDFUtils.h"
+
+static const char* as_pdf_blend_mode_name(SkBlendMode mode) {
+    const char* name = SkPDFUtils::BlendModeName(mode);
+    SkASSERT(name);
+    return name;
+}
+
+static int to_stroke_cap(uint8_t cap) {
+    // PDF32000.book section 8.4.3.3 "Line Cap Style"
+    switch ((SkPaint::Cap)cap) {
+        case SkPaint::kButt_Cap:   return 0;
+        case SkPaint::kRound_Cap:  return 1;
+        case SkPaint::kSquare_Cap: return 2;
+        default: SkASSERT(false);  return 0;
+    }
+}
+
+static int to_stroke_join(uint8_t join) {
+    // PDF32000.book section 8.4.3.4 "Line Join Style"
+    switch ((SkPaint::Join)join) {
+        case SkPaint::kMiter_Join: return 0;
+        case SkPaint::kRound_Join: return 1;
+        case SkPaint::kBevel_Join: return 2;
+        default: SkASSERT(false);  return 0;
+    }
+}
+
+// If a SkXfermode is unsupported in PDF, this function returns
+// SrcOver, otherwise, it returns that Xfermode as a Mode.
+static uint8_t pdf_blend_mode(SkBlendMode mode) {
+    if (!SkPDFUtils::BlendModeName(mode)
+        || SkBlendMode::kXor  == mode
+        || SkBlendMode::kPlus == mode)
+    {
+        mode = SkBlendMode::kSrcOver;
+    }
+    return SkToU8((unsigned)mode);
+}
+
+SkPDFIndirectReference SkPDFGraphicState::GetGraphicStateForPaint(SkPDFDocument* doc,
+                                                                  const SkPaint& p) {
+    SkASSERT(doc);
+    const SkBlendMode mode = p.getBlendMode_or(SkBlendMode::kSrcOver);
+
+    if (SkPaint::kFill_Style == p.getStyle()) {
+        SkPDFFillGraphicState fillKey = {p.getColor4f().fA, pdf_blend_mode(mode)};
+        auto& fillMap = doc->fFillGSMap;
+        if (SkPDFIndirectReference* statePtr = fillMap.find(fillKey)) {
+            return *statePtr;
+        }
+        SkPDFDict state;
+        state.reserve(2);
+        state.insertColorComponentF("ca", fillKey.fAlpha);
+        state.insertName("BM", as_pdf_blend_mode_name((SkBlendMode)fillKey.fBlendMode));
+        SkPDFIndirectReference ref = doc->emit(state);
+        fillMap.set(fillKey, ref);
+        return ref;
+    } else {
+        SkPDFStrokeGraphicState strokeKey = {
+            p.getStrokeWidth(),
+            p.getStrokeMiter(),
+            p.getColor4f().fA,
+            SkToU8(p.getStrokeCap()),
+            SkToU8(p.getStrokeJoin()),
+            pdf_blend_mode(mode)
+        };
+        auto& sMap = doc->fStrokeGSMap;
+        if (SkPDFIndirectReference* statePtr = sMap.find(strokeKey)) {
+            return *statePtr;
+        }
+        SkPDFDict state;
+        state.reserve(8);
+        state.insertColorComponentF("CA", strokeKey.fAlpha);
+        state.insertColorComponentF("ca", strokeKey.fAlpha);
+        state.insertInt("LC", to_stroke_cap(strokeKey.fStrokeCap));
+        state.insertInt("LJ", to_stroke_join(strokeKey.fStrokeJoin));
+        state.insertScalar("LW", strokeKey.fStrokeWidth);
+        state.insertScalar("ML", strokeKey.fStrokeMiter);
+        state.insertBool("SA", true);  // SA = Auto stroke adjustment.
+        state.insertName("BM", as_pdf_blend_mode_name((SkBlendMode)strokeKey.fBlendMode));
+        SkPDFIndirectReference ref = doc->emit(state);
+        sMap.set(strokeKey, ref);
+        return ref;
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+static SkPDFIndirectReference make_invert_function(SkPDFDocument* doc) {
+    // Acrobat crashes if we use a type 0 function, kpdf crashes if we use
+    // a type 2 function, so we use a type 4 function.
+    static const char psInvert[] = "{1 exch sub}";
+    // Do not copy the trailing '\0' into the SkData.
+    auto invertFunction = SkData::MakeWithoutCopy(psInvert, strlen(psInvert));
+
+    std::unique_ptr<SkPDFDict> dict = SkPDFMakeDict();
+    dict->insertInt("FunctionType", 4);
+    dict->insertObject("Domain", SkPDFMakeArray(0, 1));
+    dict->insertObject("Range", SkPDFMakeArray(0, 1));
+    return SkPDFStreamOut(std::move(dict), SkMemoryStream::Make(std::move(invertFunction)), doc);
+}
+
+SkPDFIndirectReference SkPDFGraphicState::GetSMaskGraphicState(SkPDFIndirectReference sMask,
+                                                               bool invert,
+                                                               SkPDFSMaskMode sMaskMode,
+                                                               SkPDFDocument* doc) {
+    // The practical chances of using the same mask more than once are unlikely
+    // enough that it's not worth canonicalizing.
+    auto sMaskDict = SkPDFMakeDict("Mask");
+    if (sMaskMode == kAlpha_SMaskMode) {
+        sMaskDict->insertName("S", "Alpha");
+    } else if (sMaskMode == kLuminosity_SMaskMode) {
+        sMaskDict->insertName("S", "Luminosity");
+    }
+    sMaskDict->insertRef("G", sMask);
+    if (invert) {
+        // let the doc deduplicate this object.
+        if (doc->fInvertFunction == SkPDFIndirectReference()) {
+            doc->fInvertFunction = make_invert_function(doc);
+        }
+        sMaskDict->insertRef("TR", doc->fInvertFunction);
+    }
+    SkPDFDict result("ExtGState");
+    result.insertObject("SMask", std::move(sMaskDict));
+    return doc->emit(result);
+}