SkLightingImageFilter.h revision 4b681bc95b14e081f1cc5b68cb755d57fc8eb977 
1/*
2 * Copyright 2012 The Android Open Source Project
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
9#ifndef SkLightingImageFilter_DEFINED
10#define SkLightingImageFilter_DEFINED
11
12#include "SkImageFilter.h"
13#include "SkColor.h"
14
15class SK_API SkPoint3 {
16public:
17    SkPoint3() {}
18    SkPoint3(SkScalar x, SkScalar y, SkScalar z)
19      : fX(x), fY(y), fZ(z) {}
20    SkScalar dot(const SkPoint3& other) const {
21        return SkScalarMul(fX, other.fX)
22             + SkScalarMul(fY, other.fY)
23             + SkScalarMul(fZ, other.fZ);
24    }
25    SkScalar maxComponent() const {
26        return fX > fY ? (fX > fZ ? fX : fZ) : (fY > fZ ? fY : fZ);
27    }
28    void normalize() {
29        // Small epsilon is added to prevent division by 0.
30        SkScalar scale = SkScalarInvert(SkScalarSqrt(dot(*this)) + SK_ScalarNearlyZero);
31        fX = SkScalarMul(fX, scale);
32        fY = SkScalarMul(fY, scale);
33        fZ = SkScalarMul(fZ, scale);
34    }
35    SkPoint3 operator*(SkScalar scalar) const {
36        return SkPoint3(SkScalarMul(fX, scalar),
37                        SkScalarMul(fY, scalar),
38                        SkScalarMul(fZ, scalar));
39    }
40    SkPoint3 operator-(const SkPoint3& other) const {
41        return SkPoint3(fX - other.fX, fY - other.fY, fZ - other.fZ);
42    }
43    bool operator==(const SkPoint3& other) const {
44        return fX == other.fX && fY == other.fY && fZ == other.fZ;
45    }
46    SkScalar fX, fY, fZ;
47};
48
49class SkLight;
50
51class SK_API SkLightingImageFilter : public SkImageFilter {
52public:
53    static SkImageFilter* CreateDistantLitDiffuse(const SkPoint3& direction,
54        SkColor lightColor, SkScalar surfaceScale, SkScalar kd,
55        SkImageFilter* input = NULL, const SkIRect* cropRect = NULL);
56    static SkImageFilter* CreatePointLitDiffuse(const SkPoint3& location,
57        SkColor lightColor, SkScalar surfaceScale, SkScalar kd,
58        SkImageFilter* input = NULL, const SkIRect* cropRect = NULL);
59    static SkImageFilter* CreateSpotLitDiffuse(const SkPoint3& location,
60        const SkPoint3& target, SkScalar specularExponent, SkScalar cutoffAngle,
61        SkColor lightColor, SkScalar surfaceScale, SkScalar kd,
62        SkImageFilter* input = NULL, const SkIRect* cropRect = NULL);
63    static SkImageFilter* CreateDistantLitSpecular(const SkPoint3& direction,
64        SkColor lightColor, SkScalar surfaceScale, SkScalar ks,
65        SkScalar shininess, SkImageFilter* input = NULL, const SkIRect* cropRect = NULL);
66    static SkImageFilter* CreatePointLitSpecular(const SkPoint3& location,
67        SkColor lightColor, SkScalar surfaceScale, SkScalar ks,
68        SkScalar shininess, SkImageFilter* input = NULL, const SkIRect* cropRect = NULL);
69    static SkImageFilter* CreateSpotLitSpecular(const SkPoint3& location,
70        const SkPoint3& target, SkScalar specularExponent, SkScalar cutoffAngle,
71        SkColor lightColor, SkScalar surfaceScale, SkScalar ks,
72        SkScalar shininess, SkImageFilter* input = NULL, const SkIRect* cropRect = NULL);
73    ~SkLightingImageFilter();
74
75    SK_DECLARE_FLATTENABLE_REGISTRAR_GROUP()
76
77protected:
78    SkLightingImageFilter(SkLight* light,
79                          SkScalar surfaceScale,
80                          SkImageFilter* input,
81                          const SkIRect* cropRect = NULL);
82    explicit SkLightingImageFilter(SkFlattenableReadBuffer& buffer);
83    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
84    const SkLight* light() const { return fLight; }
85    SkScalar surfaceScale() const { return fSurfaceScale; }
86
87private:
88    typedef SkImageFilter INHERITED;
89    SkLight* fLight;
90    SkScalar fSurfaceScale;
91};
92
93#endif
94