blob: cab071c747c6cff39b28d02f56d5e8833e4b60ca [file] [log] [blame]
* 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 "SkData.h"
#include "SkPaint.h"
#include "SkPDFCanon.h"
#include "SkPDFFormXObject.h"
#include "SkPDFGraphicState.h"
#include "SkPDFUtils.h"
static const char* as_pdf_blend_mode_name(SkBlendMode mode) {
// section 11.3.5 "Blend Mode"
switch (mode) {
case SkBlendMode::kScreen: return "Screen";
case SkBlendMode::kOverlay: return "Overlay";
case SkBlendMode::kDarken: return "Darken";
case SkBlendMode::kLighten: return "Lighten";
case SkBlendMode::kColorDodge: return "ColorDodge";
case SkBlendMode::kColorBurn: return "ColorBurn";
case SkBlendMode::kHardLight: return "HardLight";
case SkBlendMode::kSoftLight: return "SoftLight";
case SkBlendMode::kDifference: return "Difference";
case SkBlendMode::kExclusion: return "Exclusion";
case SkBlendMode::kMultiply: return "Multiply";
case SkBlendMode::kHue: return "Hue";
case SkBlendMode::kSaturation: return "Saturation";
case SkBlendMode::kColor: return "Color";
case SkBlendMode::kLuminosity: return "Luminosity";
// Other blendmodes are either unsupported or handled in
// SkPDFDevice::setUpContentEntry.
default: return "Normal";
static int to_stroke_cap(uint8_t cap) {
// section "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) {
// section "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) {
switch (mode) {
case SkBlendMode::kSrcOver:
case SkBlendMode::kMultiply:
case SkBlendMode::kScreen:
case SkBlendMode::kOverlay:
case SkBlendMode::kDarken:
case SkBlendMode::kLighten:
case SkBlendMode::kColorDodge:
case SkBlendMode::kColorBurn:
case SkBlendMode::kHardLight:
case SkBlendMode::kSoftLight:
case SkBlendMode::kDifference:
case SkBlendMode::kExclusion:
case SkBlendMode::kHue:
case SkBlendMode::kSaturation:
case SkBlendMode::kColor:
case SkBlendMode::kLuminosity:
return SkToU8((unsigned)mode);
return SkToU8((unsigned)SkBlendMode::kSrcOver);
sk_sp<SkPDFDict> SkPDFGraphicState::GetGraphicStateForPaint(SkPDFCanon* canon,
const SkPaint& p) {
if (SkPaint::kFill_Style == p.getStyle()) {
SkPDFFillGraphicState fillKey = {p.getAlpha(), pdf_blend_mode(p.getBlendMode())};
auto& fillMap = canon->fFillGSMap;
if (sk_sp<SkPDFDict>* statePtr = fillMap.find(fillKey)) {
return *statePtr;
auto state = sk_make_sp<SkPDFDict>();
state->insertScalar("ca", fillKey.fAlpha / 255.0f);
state->insertName("BM", as_pdf_blend_mode_name((SkBlendMode)fillKey.fBlendMode));
fillMap.set(fillKey, state);
return state;
} else {
SkPDFStrokeGraphicState strokeKey = {
p.getStrokeWidth(), p.getStrokeMiter(),
SkToU8(p.getStrokeCap()), SkToU8(p.getStrokeJoin()),
p.getAlpha(), pdf_blend_mode(p.getBlendMode())};
auto& sMap = canon->fStrokeGSMap;
if (sk_sp<SkPDFDict>* statePtr = sMap.find(strokeKey)) {
return *statePtr;
auto state = sk_make_sp<SkPDFDict>();
state->insertScalar("CA", strokeKey.fAlpha / 255.0f);
state->insertScalar("ca", strokeKey.fAlpha / 255.0f);
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));
sMap.set(strokeKey, state);
return state;
static sk_sp<SkPDFStream> make_invert_function() {
// 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.
auto domainAndRange = sk_make_sp<SkPDFArray>();
static const char psInvert[] = "{1 exch sub}";
// Do not copy the trailing '\0' into the SkData.
auto invertFunction = sk_make_sp<SkPDFStream>(
SkData::MakeWithoutCopy(psInvert, strlen(psInvert)));
invertFunction->dict()->insertInt("FunctionType", 4);
invertFunction->dict()->insertObject("Domain", domainAndRange);
invertFunction->dict()->insertObject("Range", std::move(domainAndRange));
return invertFunction;
sk_sp<SkPDFDict> SkPDFGraphicState::GetSMaskGraphicState(
sk_sp<SkPDFObject> sMask,
bool invert,
SkPDFSMaskMode sMaskMode,
SkPDFCanon* canon) {
// The practical chances of using the same mask more than once are unlikely
// enough that it's not worth canonicalizing.
auto sMaskDict = sk_make_sp<SkPDFDict>("Mask");
if (sMaskMode == kAlpha_SMaskMode) {
sMaskDict->insertName("S", "Alpha");
} else if (sMaskMode == kLuminosity_SMaskMode) {
sMaskDict->insertName("S", "Luminosity");
sMaskDict->insertObjRef("G", std::move(sMask));
if (invert) {
// Instead of calling SkPDFGraphicState::MakeInvertFunction,
// let the canon deduplicate this object.
sk_sp<SkPDFStream>& invertFunction = canon->fInvertFunction;
if (!invertFunction) {
invertFunction = make_invert_function();
sMaskDict->insertObjRef("TR", invertFunction);
auto result = sk_make_sp<SkPDFDict>("ExtGState");
result->insertObject("SMask", std::move(sMaskDict));
return result;