xref: /third_party/skia/src/gpu/GrAppliedClip.h (revision cb93a386) 
1/*
2 * Copyright 2016 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#ifndef GrAppliedClip_DEFINED
9#define GrAppliedClip_DEFINED
10
11#include "src/gpu/GrFragmentProcessor.h"
12#include "src/gpu/GrScissorState.h"
13#include "src/gpu/GrWindowRectsState.h"
14
15#include "src/core/SkClipStack.h"
16
17
18/**
19 * Produced by GrHardClip. It provides a set of modifications to the hardware drawing state that
20 * implement the clip.
21 */
22class GrAppliedHardClip {
23public:
24    static const GrAppliedHardClip& Disabled() {
25        // The size doesn't really matter here since it's returned as const& so an actual scissor
26        // will never be set on it, and applied clips are not used to query or bounds test like
27        // the GrClip is.
28        static const GrAppliedHardClip kDisabled({1 << 29, 1 << 29});
29        return kDisabled;
30    }
31
32    GrAppliedHardClip(const SkISize& rtDims) : fScissorState(rtDims) {}
33    GrAppliedHardClip(const SkISize& logicalRTDims, const SkISize& backingStoreDims)
34            : fScissorState(backingStoreDims) {
35        fScissorState.set(SkIRect::MakeSize(logicalRTDims));
36    }
37
38    GrAppliedHardClip(GrAppliedHardClip&& that) = default;
39    explicit GrAppliedHardClip(const GrAppliedHardClip&) = default;
40
41    const GrScissorState& scissorState() const { return fScissorState; }
42    const GrWindowRectsState& windowRectsState() const { return fWindowRectsState; }
43    uint32_t stencilStackID() const { return fStencilStackID; }
44    bool hasStencilClip() const { return SkClipStack::kInvalidGenID != fStencilStackID; }
45
46    /**
47     * Intersects the applied clip with the provided rect. Returns false if the draw became empty.
48     * 'clippedDrawBounds' will be intersected with 'irect'. This returns false if the clip becomes
49     * empty or the draw no longer intersects the clip. In either case the draw can be skipped.
50     */
51    bool addScissor(const SkIRect& irect, SkRect* clippedDrawBounds) {
52        return fScissorState.intersect(irect) && clippedDrawBounds->intersect(SkRect::Make(irect));
53    }
54
55    void setScissor(const SkIRect& irect) {
56        fScissorState.set(irect);
57    }
58
59    void addWindowRectangles(const GrWindowRectsState& windowState) {
60        SkASSERT(!fWindowRectsState.enabled());
61        fWindowRectsState = windowState;
62    }
63
64    void addWindowRectangles(const GrWindowRectangles& windows, GrWindowRectsState::Mode mode) {
65        SkASSERT(!fWindowRectsState.enabled());
66        fWindowRectsState.set(windows, mode);
67    }
68
69    void addStencilClip(uint32_t stencilStackID) {
70        SkASSERT(SkClipStack::kInvalidGenID == fStencilStackID);
71        fStencilStackID = stencilStackID;
72    }
73
74    bool doesClip() const {
75        return fScissorState.enabled() || this->hasStencilClip() || fWindowRectsState.enabled();
76    }
77
78    bool operator==(const GrAppliedHardClip& that) const {
79        return fScissorState == that.fScissorState &&
80               fWindowRectsState == that.fWindowRectsState &&
81               fStencilStackID == that.fStencilStackID;
82    }
83    bool operator!=(const GrAppliedHardClip& that) const { return !(*this == that); }
84
85private:
86    GrScissorState             fScissorState;
87    GrWindowRectsState         fWindowRectsState;
88    uint32_t                   fStencilStackID = SkClipStack::kInvalidGenID;
89};
90
91/**
92 * Produced by GrClip. It provides a set of modifications to GrPipeline that implement the clip.
93 */
94class GrAppliedClip {
95public:
96    static GrAppliedClip Disabled() {
97        return GrAppliedClip({1 << 29, 1 << 29});
98    }
99
100    GrAppliedClip(const SkISize& rtDims) : fHardClip(rtDims) {}
101    GrAppliedClip(const SkISize& logicalRTDims, const SkISize& backingStoreDims)
102            : fHardClip(logicalRTDims, backingStoreDims) {}
103
104    GrAppliedClip(GrAppliedClip&& that) = default;
105    GrAppliedClip(const GrAppliedClip&) = delete;
106
107    const GrScissorState& scissorState() const { return fHardClip.scissorState(); }
108    const GrWindowRectsState& windowRectsState() const { return fHardClip.windowRectsState(); }
109    uint32_t stencilStackID() const { return fHardClip.stencilStackID(); }
110    bool hasStencilClip() const { return fHardClip.hasStencilClip(); }
111    int hasCoverageFragmentProcessor() const { return fCoverageFP != nullptr; }
112    const GrFragmentProcessor* coverageFragmentProcessor() const {
113        SkASSERT(fCoverageFP != nullptr);
114        return fCoverageFP.get();
115    }
116    std::unique_ptr<GrFragmentProcessor> detachCoverageFragmentProcessor() {
117        SkASSERT(fCoverageFP != nullptr);
118        return std::move(fCoverageFP);
119    }
120
121    const GrAppliedHardClip& hardClip() const { return fHardClip; }
122    GrAppliedHardClip& hardClip() { return fHardClip; }
123
124    void addCoverageFP(std::unique_ptr<GrFragmentProcessor> fp) {
125        if (fCoverageFP == nullptr) {
126            fCoverageFP = std::move(fp);
127        } else {
128            // Compose this coverage FP with the previously-added coverage.
129            fCoverageFP = GrFragmentProcessor::Compose(std::move(fp), std::move(fCoverageFP));
130        }
131    }
132
133    bool doesClip() const {
134        return fHardClip.doesClip() || fCoverageFP != nullptr;
135    }
136
137    bool operator==(const GrAppliedClip& that) const {
138        if (fHardClip != that.fHardClip ||
139            this->hasCoverageFragmentProcessor() != that.hasCoverageFragmentProcessor()) {
140            return false;
141        }
142        if (fCoverageFP != nullptr && !fCoverageFP->isEqual(*that.fCoverageFP)) {
143            return false;
144        }
145        return true;
146    }
147    bool operator!=(const GrAppliedClip& that) const { return !(*this == that); }
148
149    void visitProxies(const GrVisitProxyFunc& func) const {
150        if (fCoverageFP != nullptr) {
151            fCoverageFP->visitProxies(func);
152        }
153    }
154
155private:
156    GrAppliedHardClip fHardClip;
157    std::unique_ptr<GrFragmentProcessor> fCoverageFP;
158};
159
160#endif
161