StencilMaskHelper.cpp | Explore in Territory

/*
 * Copyright 2020 Google LLC
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "src/gpu/ganesh/StencilMaskHelper.h"

#include "include/core/SkMatrix.h"
#include "include/core/SkPath.h"
#include "include/core/SkRect.h"
#include "include/core/SkRegion.h"
#include "include/gpu/ganesh/GrRecordingContext.h"
#include "include/private/base/SkAssert.h"
#include "include/private/gpu/ganesh/GrTypesPriv.h"
#include "src/base/SkTLazy.h"
#include "src/gpu/ganesh/GrClip.h"
#include "src/gpu/ganesh/GrDrawingManager.h"
#include "src/gpu/ganesh/GrFixedClip.h"
#include "src/gpu/ganesh/GrPaint.h"
#include "src/gpu/ganesh/GrRecordingContextPriv.h"
#include "src/gpu/ganesh/GrStencilSettings.h"
#include "src/gpu/ganesh/GrStyle.h"
#include "src/gpu/ganesh/GrUserStencilSettings.h"
#include "src/gpu/ganesh/GrWindowRectangles.h"
#include "src/gpu/ganesh/GrWindowRectsState.h"
#include "src/gpu/ganesh/PathRenderer.h"
#include "src/gpu/ganesh/PathRendererChain.h"
#include "src/gpu/ganesh/SurfaceDrawContext.h"
#include "src/gpu/ganesh/effects/GrDisableColorXP.h"
#include "src/gpu/ganesh/geometry/GrShape.h"
#include "src/gpu/ganesh/geometry/GrStyledShape.h"

#include <utility>

namespace {

////////////////////////////////////////////////////////////////////////////////
// Stencil Rules for Merging user stencil space into clip
//

///////
// Replace
static constexpr GrUserStencilSettings gUserToClipReplace(
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kNotEqual,
        0xffff,
        GrUserStencilOp::kSetClipAndReplaceUserBits,
        GrUserStencilOp::kZeroClipAndUserBits,
        0xffff>()
);

static constexpr GrUserStencilSettings gInvUserToClipReplace(
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kEqual,
        0xffff,
        GrUserStencilOp::kSetClipAndReplaceUserBits,
        GrUserStencilOp::kZeroClipAndUserBits,
        0xffff>()
);

///////
// Intersect
static constexpr GrUserStencilSettings gUserToClipIsect(
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kLessIfInClip, // "0 < userBits" is equivalent to "0 != userBits".
        0xffff,
        GrUserStencilOp::kSetClipAndReplaceUserBits,
        GrUserStencilOp::kZeroClipAndUserBits,
        0xffff>()
);

///////
// Difference
static constexpr GrUserStencilSettings gUserToClipDiff(
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kEqualIfInClip,
        0xffff,
        GrUserStencilOp::kSetClipAndReplaceUserBits,
        GrUserStencilOp::kZeroClipAndUserBits,
        0xffff>()
);

///////
// Union
static constexpr GrUserStencilSettings gUserToClipUnion(
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kNotEqual,
        0xffff,
        GrUserStencilOp::kSetClipAndReplaceUserBits,
        GrUserStencilOp::kKeep,
        0xffff>()
);

static constexpr GrUserStencilSettings gInvUserToClipUnionPass0( // Does not zero user bits.
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kEqual,
        0xffff,
        GrUserStencilOp::kSetClipBit,
        GrUserStencilOp::kKeep,
        0x0000>()
);

///////
// Xor
static constexpr GrUserStencilSettings gUserToClipXorPass0( // Does not zero user bits.
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kNotEqual,
        0xffff,
        GrUserStencilOp::kInvertClipBit,
        GrUserStencilOp::kKeep,
        0x0000>()
);

static constexpr GrUserStencilSettings gInvUserToClipXorPass0( // Does not zero user bits.
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kEqual,
        0xffff,
        GrUserStencilOp::kInvertClipBit,
        GrUserStencilOp::kKeep,
        0x0000>()
);

///////
// Reverse Diff
static constexpr GrUserStencilSettings gUserToClipRDiffPass0( // Does not zero user bits.
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kNotEqual,
        0xffff,
        GrUserStencilOp::kInvertClipBit,
        GrUserStencilOp::kZeroClipBit,
        0x0000>()
);

static constexpr GrUserStencilSettings gInvUserToClipRDiffPass0( // Does not zero user bits.
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kEqual,
        0xffff,
        GrUserStencilOp::kInvertClipBit,
        GrUserStencilOp::kZeroClipBit,
        0x0000>()
);

///////
// Second pass to clear user bits (only needed sometimes)
static constexpr GrUserStencilSettings gZeroUserBits(
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kNotEqual,
        0xffff,
        GrUserStencilOp::kZero,
        GrUserStencilOp::kKeep,
        0xffff>()
);

static constexpr const GrUserStencilSettings* gUserToClipTable[2][1 + SkRegion::kLastOp][3] = …;

///////
// Direct to Stencil

// We can render a clip element directly without first writing to the client
// portion of the clip when the fill is not inverse and the set operation will
// only modify the in/out status of samples covered by the clip element.

// this one only works if used right after stencil clip was cleared.
// Our clip mask creation code doesn't allow midstream replace ops.
static constexpr GrUserStencilSettings gReplaceClip(
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kAlways,
        0xffff,
        GrUserStencilOp::kSetClipBit,
        GrUserStencilOp::kSetClipBit,
        0x0000>()
);

static constexpr GrUserStencilSettings gUnionClip(
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kAlwaysIfInClip,
        0xffff,
        GrUserStencilOp::kKeep,
        GrUserStencilOp::kSetClipBit,
        0x0000>()
);

static constexpr GrUserStencilSettings gXorClip(
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kAlways,
        0xffff,
        GrUserStencilOp::kInvertClipBit,
        GrUserStencilOp::kInvertClipBit,
        0x0000>()
);

static constexpr GrUserStencilSettings gDiffClip(
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kAlwaysIfInClip,
        0xffff,
        GrUserStencilOp::kZeroClipBit,
        GrUserStencilOp::kKeep,
        0x0000>()
);

static constexpr const GrUserStencilSettings* gDirectDrawTable[1 + SkRegion::kLastOp][2] = …;

static_assert …;
static_assert …;
static_assert …;
static_assert …;
static_assert …;
static_assert …;

// Settings used to when not allowed to draw directly to the clip to fill the user stencil bits
// before applying the covering clip stencil passes.
static constexpr GrUserStencilSettings gDrawToStencil(
    GrUserStencilSettings::StaticInit<
        0x0000,
        GrUserStencilTest::kAlways,
        0xffff,
        GrUserStencilOp::kIncMaybeClamp,
        GrUserStencilOp::kIncMaybeClamp,
        0xffff>()
);

// Get the stencil settings per-pass to achieve the given fill+region op effect on the
// stencil buffer.
//
// If drawDirectToClip comes back false, the caller must first draw the element into the user
// stencil bits, and then cover the clip area with multiple passes using the returned
// stencil settings.

// If drawDirectToClip is true, the returned array will only have one pass and the
// caller should use those stencil settings while drawing the element directly.
//
// This returns a null-terminated list of const GrUserStencilSettings*
GrUserStencilSettings const* const* get_stencil_passes(
        SkRegion::Op op,
        skgpu::ganesh::PathRenderer::StencilSupport stencilSupport,
        bool fillInverted,
        bool* drawDirectToClip) { … }

void draw_stencil_rect(skgpu::ganesh::SurfaceDrawContext* sdc,
                       const GrHardClip& clip,
                       const GrUserStencilSettings* ss,
                       const SkMatrix& matrix,
                       const SkRect& rect,
                       GrAA aa) { … }

void draw_path(GrRecordingContext* rContext,
               skgpu::ganesh::SurfaceDrawContext* sdc,
               skgpu::ganesh::PathRenderer* pr,
               const GrHardClip& clip,
               const SkIRect& bounds,
               const GrUserStencilSettings* ss,
               const SkMatrix& matrix,
               const GrStyledShape& shape,
               GrAA aa) { … }

void stencil_path(GrRecordingContext* rContext,
                  skgpu::ganesh::SurfaceDrawContext* sdc,
                  skgpu::ganesh::PathRenderer* pr,
                  const GrFixedClip& clip,
                  const SkMatrix& matrix,
                  const GrStyledShape& shape,
                  GrAA aa) { … }

GrAA supported_aa(skgpu::ganesh::SurfaceDrawContext* sdc, GrAA aa) { … }

}  // namespace

namespace skgpu::ganesh {

StencilMaskHelper::StencilMaskHelper(GrRecordingContext* rContext,
                                     SurfaceDrawContext* sdc)
        : … { … }

bool StencilMaskHelper::init(const SkIRect& bounds, uint32_t genID,
                             const GrWindowRectangles& windowRects, int numFPs) { … }

void StencilMaskHelper::drawRect(const SkRect& rect,
                                 const SkMatrix& matrix,
                                 SkRegion::Op op,
                                 GrAA aa) { … }

bool StencilMaskHelper::drawPath(const SkPath& path,
                                 const SkMatrix& matrix,
                                 SkRegion::Op op,
                                 GrAA aa) { … }

bool StencilMaskHelper::drawShape(const GrShape& shape,
                                  const SkMatrix& matrix,
                                  SkRegion::Op op,
                                  GrAA aa) { … }

void StencilMaskHelper::clear(bool insideStencil) { … }

void StencilMaskHelper::finish() { … }

}  // namespace skgpu::ganesh
chromium/third_party/skia/src/gpu/ganesh/StencilMaskHelper.cpp
