xref: /third_party/skia/src/gpu/ops/ClearOp.cpp (revision cb93a386) 
1/*
2 * Copyright 2017 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#include "src/gpu/ops/ClearOp.h"
9
10#include "include/gpu/GrRecordingContext.h"
11#include "src/gpu/GrMemoryPool.h"
12#include "src/gpu/GrOpFlushState.h"
13#include "src/gpu/GrOpsRenderPass.h"
14#include "src/gpu/GrProxyProvider.h"
15#include "src/gpu/GrRecordingContextPriv.h"
16
17namespace {
18
19bool contains_scissor(const GrScissorState& a, const GrScissorState& b) {
20    return !a.enabled() || (b.enabled() && a.rect().contains(b.rect()));
21}
22
23} // anonymous namespace
24
25namespace skgpu::v1 {
26
27GrOp::Owner ClearOp::MakeColor(GrRecordingContext* context,
28                               const GrScissorState& scissor,
29                               std::array<float, 4> color) {
30    return GrOp::Make<ClearOp>(context, Buffer::kColor, scissor, color, false);
31}
32
33GrOp::Owner ClearOp::MakeStencilClip(GrRecordingContext* context,
34                                     const GrScissorState& scissor,
35                                     bool insideMask) {
36    return GrOp::Make<ClearOp>(context,
37                               Buffer::kStencilClip,
38                               scissor,
39                               std::array<float, 4>(),
40                               insideMask);
41}
42
43ClearOp::ClearOp(Buffer buffer,
44                 const GrScissorState& scissor,
45                 std::array<float, 4> color,
46                 bool insideMask)
47        : GrOp(ClassID())
48        , fScissor(scissor)
49        , fColor(color)
50        , fStencilInsideMask(insideMask)
51        , fBuffer(buffer) {
52    this->setBounds(SkRect::Make(scissor.rect()), HasAABloat::kNo, IsHairline::kNo);
53}
54
55GrOp::CombineResult ClearOp::onCombineIfPossible(GrOp* t, SkArenaAlloc*, const GrCaps& caps) {
56    auto other = t->cast<ClearOp>();
57
58    if (other->fBuffer == fBuffer) {
59        // This could be much more complicated. Currently we look at cases where the new clear
60        // contains the old clear, or when the new clear is a subset of the old clear and they clear
61        // to the same value (color or stencil mask depending on target).
62        if (contains_scissor(other->fScissor, fScissor)) {
63            fScissor = other->fScissor;
64            fColor = other->fColor;
65            fStencilInsideMask = other->fStencilInsideMask;
66            return CombineResult::kMerged;
67        } else if (other->fColor == fColor && other->fStencilInsideMask == fStencilInsideMask &&
68                   contains_scissor(fScissor, other->fScissor)) {
69            return CombineResult::kMerged;
70        }
71    } else if (other->fScissor == fScissor) {
72        // When the scissors are the exact same but the buffers are different, we can combine and
73        // clear both stencil and clear together in onExecute().
74        if (other->fBuffer & Buffer::kColor) {
75            fColor = other->fColor;
76        }
77        if (other->fBuffer & Buffer::kStencilClip) {
78            fStencilInsideMask = other->fStencilInsideMask;
79        }
80        fBuffer = Buffer::kBoth;
81        return CombineResult::kMerged;
82    }
83    return CombineResult::kCannotCombine;
84}
85
86void ClearOp::onExecute(GrOpFlushState* state, const SkRect& chainBounds) {
87    SkASSERT(state->opsRenderPass());
88    if (fBuffer & Buffer::kColor) {
89        state->opsRenderPass()->clear(fScissor, fColor);
90    }
91
92    if (fBuffer & Buffer::kStencilClip) {
93        state->opsRenderPass()->clearStencilClip(fScissor, fStencilInsideMask);
94    }
95}
96
97} // namespace skgpu::v1
98
99