1/*
2 * Copyright 2011 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 "Test.h"
9#include "TestClassDef.h"
10#include "SkPath.h"
11#include "SkCanvas.h"
12
13static void appendStr(SkString* str, const SkPaint& paint) {
14    str->appendf(" style[%d] cap[%d] join[%d] antialias[%d]",
15                 paint.getStyle(), paint.getStrokeCap(),
16                 paint.getStrokeJoin(), paint.isAntiAlias());
17}
18
19static void appendStr(SkString* str, const SkPath& path) {
20    str->appendf(" filltype[%d] ptcount[%d]",
21                 path.getFillType(), path.countPoints());
22}
23
24#define DIMENSION   32
25
26static void drawAndTest(skiatest::Reporter* reporter, const SkPath& path,
27                        const SkPaint& paint, bool shouldDraw) {
28    SkBitmap bm;
29    // explicitly specify a trim rowbytes, so we have no padding on each row
30    bm.setConfig(SkBitmap::kARGB_8888_Config, DIMENSION, DIMENSION, DIMENSION*4);
31    bm.allocPixels();
32    bm.eraseColor(SK_ColorTRANSPARENT);
33
34    SkCanvas canvas(bm);
35    SkPaint p(paint);
36    p.setColor(SK_ColorWHITE);
37
38    canvas.drawPath(path, p);
39
40    size_t count = DIMENSION * DIMENSION;
41    const SkPMColor* ptr = bm.getAddr32(0, 0);
42
43    SkPMColor andValue = ~0U;
44    SkPMColor orValue = 0;
45    for (size_t i = 0; i < count; ++i) {
46        SkPMColor c = ptr[i];
47        andValue &= c;
48        orValue |= c;
49    }
50
51    // success means we drew everywhere or nowhere (depending on shouldDraw)
52    bool success = shouldDraw ? (~0U == andValue) : (0 == orValue);
53
54    if (!success) {
55        SkString str;
56        if (shouldDraw) {
57            str.set("Path expected to draw everywhere, but didn't. ");
58        } else {
59            str.set("Path expected to draw nowhere, but did. ");
60        }
61        appendStr(&str, paint);
62        appendStr(&str, path);
63        reporter->reportFailed(str);
64
65// uncomment this if you want to step in to see the failure
66//        canvas.drawPath(path, p);
67    }
68}
69
70static void iter_paint(skiatest::Reporter* reporter, const SkPath& path, bool shouldDraw) {
71    static const SkPaint::Cap gCaps[] = {
72        SkPaint::kButt_Cap,
73        SkPaint::kRound_Cap,
74        SkPaint::kSquare_Cap
75    };
76    static const SkPaint::Join gJoins[] = {
77        SkPaint::kMiter_Join,
78        SkPaint::kRound_Join,
79        SkPaint::kBevel_Join
80    };
81    static const SkPaint::Style gStyles[] = {
82        SkPaint::kFill_Style,
83        SkPaint::kStroke_Style,
84        SkPaint::kStrokeAndFill_Style
85    };
86    for (size_t cap = 0; cap < SK_ARRAY_COUNT(gCaps); ++cap) {
87        for (size_t join = 0; join < SK_ARRAY_COUNT(gJoins); ++join) {
88            for (size_t style = 0; style < SK_ARRAY_COUNT(gStyles); ++style) {
89                SkPaint paint;
90                paint.setStrokeWidth(SkIntToScalar(10));
91
92                paint.setStrokeCap(gCaps[cap]);
93                paint.setStrokeJoin(gJoins[join]);
94                paint.setStyle(gStyles[style]);
95
96                paint.setAntiAlias(false);
97                drawAndTest(reporter, path, paint, shouldDraw);
98                paint.setAntiAlias(true);
99                drawAndTest(reporter, path, paint, shouldDraw);
100            }
101        }
102    }
103}
104
105#define CX  (SkIntToScalar(DIMENSION) / 2)
106#define CY  (SkIntToScalar(DIMENSION) / 2)
107
108static void make_empty(SkPath*) {}
109static void make_M(SkPath* path) { path->moveTo(CX, CY); }
110static void make_MM(SkPath* path) { path->moveTo(CX, CY); path->moveTo(CX, CY); }
111static void make_MZM(SkPath* path) { path->moveTo(CX, CY); path->close(); path->moveTo(CX, CY); }
112static void make_L(SkPath* path) { path->moveTo(CX, CY); path->lineTo(CX, CY); }
113static void make_Q(SkPath* path) { path->moveTo(CX, CY); path->quadTo(CX, CY, CX, CY); }
114static void make_C(SkPath* path) { path->moveTo(CX, CY); path->cubicTo(CX, CY, CX, CY, CX, CY); }
115
116/*  Two invariants are tested: How does an empty/degenerate path draw?
117 *  - if the path is drawn inverse, it should draw everywhere
118 *  - if the path is drawn non-inverse, it should draw nowhere
119 *
120 *  Things to iterate on:
121 *  - path (empty, degenerate line/quad/cubic w/ and w/o close
122 *  - paint style
123 *  - path filltype
124 *  - path stroke variants (e.g. caps, joins, width)
125 */
126static void test_emptydrawing(skiatest::Reporter* reporter) {
127    static void (*gMakeProc[])(SkPath*) = {
128        make_empty, make_M, make_MM, make_MZM, make_L, make_Q, make_C
129    };
130    static SkPath::FillType gFills[] = {
131        SkPath::kWinding_FillType,
132        SkPath::kEvenOdd_FillType,
133        SkPath::kInverseWinding_FillType,
134        SkPath::kInverseEvenOdd_FillType
135    };
136    for (int doClose = 0; doClose < 2; ++doClose) {
137        for  (size_t i = 0; i < SK_ARRAY_COUNT(gMakeProc); ++i) {
138            SkPath path;
139            gMakeProc[i](&path);
140            if (doClose) {
141                path.close();
142            }
143            for (size_t fill = 0; fill < SK_ARRAY_COUNT(gFills); ++fill) {
144                path.setFillType(gFills[fill]);
145                bool shouldDraw = path.isInverseFillType();
146                iter_paint(reporter, path, shouldDraw);
147            }
148        }
149    }
150}
151
152DEF_TEST(EmptyPath, reporter) {
153    test_emptydrawing(reporter);
154}
155