GrPathRendererChain.cpp revision 45a15f551b5b3c6c747d8eaf6466b7d3b76a8fae 
1
2/*
3 * Copyright 2011 Google Inc.
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9
10#include "GrPathRendererChain.h"
11
12#include "GrContext.h"
13#include "GrDefaultPathRenderer.h"
14#include "GrGpu.h"
15
16SK_DEFINE_INST_COUNT(GrPathRendererChain)
17
18GrPathRendererChain::GrPathRendererChain(GrContext* context)
19    : fInit(false)
20    , fOwner(context) {
21}
22
23GrPathRendererChain::~GrPathRendererChain() {
24    for (int i = 0; i < fChain.count(); ++i) {
25        fChain[i]->unref();
26    }
27}
28
29GrPathRenderer* GrPathRendererChain::addPathRenderer(GrPathRenderer* pr) {
30    fChain.push_back() = pr;
31    pr->ref();
32    return pr;
33}
34
35GrPathRenderer* GrPathRendererChain::getPathRenderer(const SkPath& path,
36                                                     const SkStroke& stroke,
37                                                     const GrDrawTarget* target,
38                                                     DrawType drawType,
39                                                     StencilSupport* stencilSupport) {
40    if (!fInit) {
41        this->init();
42    }
43    bool antiAlias = (kColorAntiAlias_DrawType == drawType ||
44                      kStencilAndColorAntiAlias_DrawType == drawType);
45
46    GR_STATIC_ASSERT(GrPathRenderer::kNoSupport_StencilSupport <
47                     GrPathRenderer::kStencilOnly_StencilSupport);
48    GR_STATIC_ASSERT(GrPathRenderer::kStencilOnly_StencilSupport <
49                     GrPathRenderer::kNoRestriction_StencilSupport);
50    GrPathRenderer::StencilSupport minStencilSupport;
51    if (kStencilOnly_DrawType == drawType) {
52        minStencilSupport = GrPathRenderer::kStencilOnly_StencilSupport;
53    } else if (kStencilAndColor_DrawType == drawType ||
54               kStencilAndColorAntiAlias_DrawType == drawType) {
55        minStencilSupport = GrPathRenderer::kNoRestriction_StencilSupport;
56    } else {
57        minStencilSupport = GrPathRenderer::kNoSupport_StencilSupport;
58    }
59
60
61    for (int i = 0; i < fChain.count(); ++i) {
62        if (fChain[i]->canDrawPath(path, stroke, target, antiAlias)) {
63            if (GrPathRenderer::kNoSupport_StencilSupport != minStencilSupport) {
64                GrPathRenderer::StencilSupport support = fChain[i]->getStencilSupport(path,
65                                                                                      stroke,
66                                                                                      target);
67                if (support < minStencilSupport) {
68                    continue;
69                } else if (NULL != stencilSupport) {
70                    *stencilSupport = support;
71                }
72            }
73            return fChain[i];
74        }
75    }
76    return NULL;
77}
78
79void GrPathRendererChain::init() {
80    GrAssert(!fInit);
81    GrGpu* gpu = fOwner->getGpu();
82    bool twoSided = gpu->getCaps().twoSidedStencilSupport();
83    bool wrapOp = gpu->getCaps().stencilWrapOpsSupport();
84    GrPathRenderer::AddPathRenderers(fOwner, this);
85    this->addPathRenderer(SkNEW_ARGS(GrDefaultPathRenderer,
86                                     (twoSided, wrapOp)))->unref();
87    fInit = true;
88}
89