aboutsummaryrefslogtreecommitdiffhomepage
path: root/src/gpu/gl/GrGLPath.cpp
blob: 0b35a7007f6a54fc527dbbcb4f615adafe8d3036 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229

/*
 * Copyright 2012 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "GrGLPath.h"
#include "GrGLPathRendering.h"
#include "GrGLGpu.h"

namespace {
inline GrGLubyte verb_to_gl_path_cmd(SkPath::Verb verb) {
    static const GrGLubyte gTable[] = {
        GR_GL_MOVE_TO,
        GR_GL_LINE_TO,
        GR_GL_QUADRATIC_CURVE_TO,
        GR_GL_CONIC_CURVE_TO,
        GR_GL_CUBIC_CURVE_TO,
        GR_GL_CLOSE_PATH,
    };
    GR_STATIC_ASSERT(0 == SkPath::kMove_Verb);
    GR_STATIC_ASSERT(1 == SkPath::kLine_Verb);
    GR_STATIC_ASSERT(2 == SkPath::kQuad_Verb);
    GR_STATIC_ASSERT(3 == SkPath::kConic_Verb);
    GR_STATIC_ASSERT(4 == SkPath::kCubic_Verb);
    GR_STATIC_ASSERT(5 == SkPath::kClose_Verb);

    SkASSERT(verb >= 0 && (size_t)verb < SK_ARRAY_COUNT(gTable));
    return gTable[verb];
}

#ifdef SK_DEBUG
inline int num_coords(SkPath::Verb verb) {
    static const int gTable[] = {
        2, // move
        2, // line
        4, // quad
        5, // conic
        6, // cubic
        0, // close
    };
    GR_STATIC_ASSERT(0 == SkPath::kMove_Verb);
    GR_STATIC_ASSERT(1 == SkPath::kLine_Verb);
    GR_STATIC_ASSERT(2 == SkPath::kQuad_Verb);
    GR_STATIC_ASSERT(3 == SkPath::kConic_Verb);
    GR_STATIC_ASSERT(4 == SkPath::kCubic_Verb);
    GR_STATIC_ASSERT(5 == SkPath::kClose_Verb);

    SkASSERT(verb >= 0 && (size_t)verb < SK_ARRAY_COUNT(gTable));
    return gTable[verb];
}
#endif

inline GrGLenum join_to_gl_join(SkPaint::Join join) {
    static GrGLenum gSkJoinsToGrGLJoins[] = {
        GR_GL_MITER_REVERT,
        GR_GL_ROUND,
        GR_GL_BEVEL
    };
    return gSkJoinsToGrGLJoins[join];
    GR_STATIC_ASSERT(0 == SkPaint::kMiter_Join);
    GR_STATIC_ASSERT(1 == SkPaint::kRound_Join);
    GR_STATIC_ASSERT(2 == SkPaint::kBevel_Join);
    GR_STATIC_ASSERT(SK_ARRAY_COUNT(gSkJoinsToGrGLJoins) == SkPaint::kJoinCount);
}

inline GrGLenum cap_to_gl_cap(SkPaint::Cap cap) {
    static GrGLenum gSkCapsToGrGLCaps[] = {
        GR_GL_FLAT,
        GR_GL_ROUND,
        GR_GL_SQUARE
    };
    return gSkCapsToGrGLCaps[cap];
    GR_STATIC_ASSERT(0 == SkPaint::kButt_Cap);
    GR_STATIC_ASSERT(1 == SkPaint::kRound_Cap);
    GR_STATIC_ASSERT(2 == SkPaint::kSquare_Cap);
    GR_STATIC_ASSERT(SK_ARRAY_COUNT(gSkCapsToGrGLCaps) == SkPaint::kCapCount);
}

inline void points_to_coords(const SkPoint points[], size_t first_point, size_t amount,
                             GrGLfloat coords[]) {
    for (size_t i = 0;  i < amount; ++i) {
        coords[i * 2] =  SkScalarToFloat(points[first_point + i].fX);
        coords[i * 2 + 1] = SkScalarToFloat(points[first_point + i].fY);
    }
}
}

void GrGLPath::InitPathObject(GrGLGpu* gpu,
                              GrGLuint pathID,
                              const SkPath& skPath,
                              const GrStrokeInfo& stroke) {
    SkASSERT(!stroke.isDashed());
    if (!skPath.isEmpty()) {
        int verbCnt = skPath.countVerbs();
        int pointCnt = skPath.countPoints();
        int minCoordCnt = pointCnt * 2;

        SkSTArray<16, GrGLubyte, true> pathCommands(verbCnt);
        SkSTArray<16, GrGLfloat, true> pathCoords(minCoordCnt);

        SkDEBUGCODE(int numCoords = 0);

        if ((skPath.getSegmentMasks() & SkPath::kConic_SegmentMask) == 0) {
            // This branch does type punning, converting SkPoint* to GrGLfloat*.
            SK_COMPILE_ASSERT(sizeof(SkPoint) == sizeof(GrGLfloat) * 2, sk_point_not_two_floats);
            // This branch does not convert with SkScalarToFloat.
#ifndef SK_SCALAR_IS_FLOAT
#error Need SK_SCALAR_IS_FLOAT.
#endif
            pathCommands.resize_back(verbCnt);
            pathCoords.resize_back(minCoordCnt);
            skPath.getPoints(reinterpret_cast<SkPoint*>(&pathCoords[0]), pointCnt);
            skPath.getVerbs(&pathCommands[0], verbCnt);
            for (int i = 0; i < verbCnt; ++i) {
                SkPath::Verb v = static_cast<SkPath::Verb>(pathCommands[i]);
                pathCommands[i] = verb_to_gl_path_cmd(v);
                SkDEBUGCODE(numCoords += num_coords(v));
            }
        } else {
            SkPoint points[4];
            SkPath::RawIter iter(skPath);
            SkPath::Verb verb;
            while ((verb = iter.next(points)) != SkPath::kDone_Verb) {
                pathCommands.push_back(verb_to_gl_path_cmd(verb));
                GrGLfloat coords[6];
                int coordsForVerb;
                switch (verb) {
                    case SkPath::kMove_Verb:
                        points_to_coords(points, 0, 1, coords);
                        coordsForVerb = 2;
                        break;
                    case SkPath::kLine_Verb:
                        points_to_coords(points, 1, 1, coords);
                        coordsForVerb = 2;
                        break;
                    case SkPath::kConic_Verb:
                        points_to_coords(points, 1, 2, coords);
                        coords[4] = SkScalarToFloat(iter.conicWeight());
                        coordsForVerb = 5;
                        break;
                    case SkPath::kQuad_Verb:
                        points_to_coords(points, 1, 2, coords);
                        coordsForVerb = 4;
                        break;
                    case SkPath::kCubic_Verb:
                        points_to_coords(points, 1, 3, coords);
                        coordsForVerb = 6;
                        break;
                    case SkPath::kClose_Verb:
                        continue;
                    default:
                        SkASSERT(false);  // Not reached.
                        continue;
                }
                SkDEBUGCODE(numCoords += num_coords(verb));
                pathCoords.push_back_n(coordsForVerb, coords);
            }
        }

        SkASSERT(verbCnt == pathCommands.count());
        SkASSERT(numCoords == pathCoords.count());

        GR_GL_CALL(gpu->glInterface(), PathCommands(pathID, pathCommands.count(), &pathCommands[0],
                   pathCoords.count(), GR_GL_FLOAT, &pathCoords[0]));
    } else {
        GR_GL_CALL(gpu->glInterface(), PathCommands(pathID, 0, NULL, 0, GR_GL_FLOAT, NULL));
    }

    if (stroke.needToApply()) {
        SkASSERT(!stroke.isHairlineStyle());
        GR_GL_CALL(gpu->glInterface(),
            PathParameterf(pathID, GR_GL_PATH_STROKE_WIDTH, SkScalarToFloat(stroke.getWidth())));
        GR_GL_CALL(gpu->glInterface(),
            PathParameterf(pathID, GR_GL_PATH_MITER_LIMIT, SkScalarToFloat(stroke.getMiter())));
        GrGLenum join = join_to_gl_join(stroke.getJoin());
        GR_GL_CALL(gpu->glInterface(), PathParameteri(pathID, GR_GL_PATH_JOIN_STYLE, join));
        GrGLenum cap = cap_to_gl_cap(stroke.getCap());
        GR_GL_CALL(gpu->glInterface(), PathParameteri(pathID, GR_GL_PATH_END_CAPS, cap));
        GR_GL_CALL(gpu->glInterface(), PathParameterf(pathID, GR_GL_PATH_STROKE_BOUND, 0.02f));
    }
}

GrGLPath::GrGLPath(GrGLGpu* gpu, const SkPath& origSkPath, const GrStrokeInfo& origStroke)
    : INHERITED(gpu, origSkPath, origStroke),
      fPathID(gpu->glPathRendering()->genPaths(1)) {
    // Convert a dashing to either a stroke or a fill.
    const SkPath* skPath = &origSkPath;
    SkTLazy<SkPath> tmpPath;
    const GrStrokeInfo* stroke = &origStroke;
    GrStrokeInfo tmpStroke(SkStrokeRec::kFill_InitStyle);

    if (stroke->isDashed()) {
        if (stroke->applyDashToPath(tmpPath.init(), &tmpStroke, *skPath)) {
            skPath = tmpPath.get();
            stroke = &tmpStroke;
        }
    }

    InitPathObject(gpu, fPathID, *skPath, *stroke);

    fShouldStroke = stroke->needToApply();
    fShouldFill = stroke->isFillStyle() ||
            stroke->getStyle() == SkStrokeRec::kStrokeAndFill_Style;

    if (fShouldStroke) {
        // FIXME: try to account for stroking, without rasterizing the stroke.
        fBounds.outset(stroke->getWidth(), stroke->getWidth());
    }

    this->registerWithCache();
}

void GrGLPath::onRelease() {
    if (0 != fPathID && this->shouldFreeResources()) {
        static_cast<GrGLGpu*>(this->getGpu())->glPathRendering()->deletePaths(fPathID, 1);
        fPathID = 0;
    }

    INHERITED::onRelease();
}

void GrGLPath::onAbandon() {
    fPathID = 0;

    INHERITED::onAbandon();
}