1
2/*
3 * Copyright 2006 The Android Open Source Project
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 "SkDrawGradient.h"
11#include "SkAnimateMaker.h"
12#include "SkAnimatorScript.h"
13#include "SkGradientShader.h"
14#include "SkUnitMapper.h"
15
16SkScalar SkUnitToScalar(U16CPU x) {
17#ifdef SK_SCALAR_IS_FLOAT
18    return x / 65535.0f;
19#else
20    return x + (x >> 8);
21#endif
22}
23
24U16CPU SkScalarToUnit(SkScalar x) {
25    SkScalar pin =  SkScalarPin(x, 0, SK_Scalar1);
26#ifdef SK_SCALAR_IS_FLOAT
27    return (int) (pin * 65535.0f);
28#else
29    return pin - (pin >= 32768);
30#endif
31}
32
33class SkGradientUnitMapper : public SkUnitMapper {
34public:
35    SkGradientUnitMapper(SkAnimateMaker* maker, const char* script) : fMaker(maker), fScript(script) {
36    }
37
38    // overrides for SkFlattenable
39    virtual Factory getFactory() { return NULL; }
40
41protected:
42    virtual uint16_t mapUnit16(uint16_t x) {
43        fUnit = SkUnitToScalar(x);
44        SkScriptValue value;
45        SkAnimatorScript engine(*fMaker, NULL, SkType_Float);
46        engine.propertyCallBack(GetUnitValue, &fUnit);
47        if (engine.evaluate(fScript, &value, SkType_Float))
48            x = SkScalarToUnit(value.fOperand.fScalar);
49        return x;
50    }
51
52    static bool GetUnitValue(const char* token, size_t len, void* unitPtr, SkScriptValue* value) {
53        if (SK_LITERAL_STR_EQUAL("unit", token, len)) {
54            value->fOperand.fScalar = *(SkScalar*) unitPtr;
55            value->fType = SkType_Float;
56            return true;
57        }
58        return false;
59    }
60
61    SkAnimateMaker* fMaker;
62    const char* fScript;
63    SkScalar fUnit;
64};
65
66
67#if SK_USE_CONDENSED_INFO == 0
68
69const SkMemberInfo SkGradient::fInfo[] = {
70    SK_MEMBER_INHERITED,
71    SK_MEMBER_ARRAY(offsets, Float),
72    SK_MEMBER(unitMapper, String)
73};
74
75#endif
76
77DEFINE_GET_MEMBER(SkGradient);
78
79SkGradient::SkGradient() : fUnitMapper(NULL) {
80}
81
82SkGradient::~SkGradient() {
83    for (int index = 0; index < fDrawColors.count(); index++)
84        delete fDrawColors[index];
85    delete fUnitMapper;
86}
87
88bool SkGradient::add(SkAnimateMaker& , SkDisplayable* child) {
89    SkASSERT(child);
90    if (child->isColor()) {
91        SkDrawColor* color = (SkDrawColor*) child;
92        *fDrawColors.append() = color;
93        return true;
94    }
95    return false;
96}
97
98int SkGradient::addPrelude() {
99    int count = fDrawColors.count();
100    fColors.setCount(count);
101    for (int index = 0; index < count; index++)
102        fColors[index] = fDrawColors[index]->color;
103    return count;
104}
105
106#ifdef SK_DUMP_ENABLED
107void SkGradient::dumpRest(SkAnimateMaker* maker) {
108    dumpAttrs(maker);
109    //can a gradient have no colors?
110    bool closedYet = false;
111    SkDisplayList::fIndent += 4;
112    for (SkDrawColor** ptr = fDrawColors.begin(); ptr < fDrawColors.end(); ptr++) {
113        if (closedYet == false) {
114            SkDebugf(">\n");
115            closedYet = true;
116        }
117        SkDrawColor* color = *ptr;
118        color->dump(maker);
119    }
120    SkDisplayList::fIndent -= 4;
121    dumpChildren(maker, closedYet); //dumps the matrix if it has one
122}
123#endif
124
125void SkGradient::onEndElement(SkAnimateMaker& maker) {
126    if (offsets.count() != 0) {
127        if (offsets.count() != fDrawColors.count()) {
128            maker.setErrorCode(SkDisplayXMLParserError::kGradientOffsetsDontMatchColors);
129            return;
130        }
131        if (offsets[0] != 0) {
132            maker.setErrorCode(SkDisplayXMLParserError::kGradientOffsetsMustStartWithZero);
133            return;
134        }
135        if (offsets[offsets.count()-1] != SK_Scalar1) {
136            maker.setErrorCode(SkDisplayXMLParserError::kGradientOffsetsMustEndWithOne);
137            return;
138        }
139        for (int i = 1; i < offsets.count(); i++) {
140            if (offsets[i] <= offsets[i-1]) {
141                maker.setErrorCode(SkDisplayXMLParserError::kGradientOffsetsMustIncrease);
142                return;
143            }
144            if (offsets[i] > SK_Scalar1) {
145                maker.setErrorCode(SkDisplayXMLParserError::kGradientOffsetsMustBeNoMoreThanOne);
146                return;
147            }
148        }
149    }
150    if (unitMapper.size() > 0)
151        fUnitMapper = new SkGradientUnitMapper(&maker, unitMapper.c_str());
152    INHERITED::onEndElement(maker);
153}
154
155#if SK_USE_CONDENSED_INFO == 0
156
157const SkMemberInfo SkLinearGradient::fInfo[] = {
158    SK_MEMBER_INHERITED,
159    SK_MEMBER_ARRAY(points, Float),
160};
161
162#endif
163
164DEFINE_GET_MEMBER(SkLinearGradient);
165
166SkLinearGradient::SkLinearGradient() {
167}
168
169void SkLinearGradient::onEndElement(SkAnimateMaker& maker)
170{
171    if (points.count() != 4)
172        maker.setErrorCode(SkDisplayXMLParserError::kGradientPointsLengthMustBeFour);
173    INHERITED::onEndElement(maker);
174}
175
176#ifdef SK_DUMP_ENABLED
177void SkLinearGradient::dump(SkAnimateMaker* maker) {
178    dumpBase(maker);
179    dumpRest(maker);
180    }
181#endif
182
183SkShader* SkLinearGradient::getShader() {
184    if (addPrelude() == 0 || points.count() != 4)
185        return NULL;
186    SkShader* shader = SkGradientShader::CreateLinear((SkPoint*)points.begin(),
187        fColors.begin(), offsets.begin(), fColors.count(), (SkShader::TileMode) tileMode, fUnitMapper);
188    SkAutoTDelete<SkShader> autoDel(shader);
189    addPostlude(shader);
190    (void)autoDel.detach();
191    return shader;
192}
193
194
195#if SK_USE_CONDENSED_INFO == 0
196
197const SkMemberInfo SkRadialGradient::fInfo[] = {
198    SK_MEMBER_INHERITED,
199    SK_MEMBER(center, Point),
200    SK_MEMBER(radius, Float)
201};
202
203#endif
204
205DEFINE_GET_MEMBER(SkRadialGradient);
206
207SkRadialGradient::SkRadialGradient() : radius(0) {
208    center.set(0, 0);
209}
210
211#ifdef SK_DUMP_ENABLED
212void SkRadialGradient::dump(SkAnimateMaker* maker) {
213    dumpBase(maker);
214    dumpRest(maker);
215}
216#endif
217
218SkShader* SkRadialGradient::getShader() {
219    if (addPrelude() == 0)
220        return NULL;
221    SkShader* shader = SkGradientShader::CreateRadial(center,
222        radius, fColors.begin(), offsets.begin(), fColors.count(), (SkShader::TileMode) tileMode, fUnitMapper);
223    SkAutoTDelete<SkShader> autoDel(shader);
224    addPostlude(shader);
225    (void)autoDel.detach();
226    return shader;
227}
228