SkLightingImageFilter.h revision 1a5e51f94ed8cb01600184119e52bb64bdb3dccc 
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#ifndef SkLightingImageFilter_DEFINED
9#define SkLightingImageFilter_DEFINED
10
11#include "SkImageFilter.h"
12#include "SkColor.h"
13
14class SK_API SkPoint3 {
15public:
16    SkPoint3() {}
17    SkPoint3(SkScalar x, SkScalar y, SkScalar z)
18      : fX(x), fY(y), fZ(z) {}
19    SkScalar dot(const SkPoint3& other) const {
20        return fX * other.fX + fY * other.fY + fZ * other.fZ;
21    }
22    SkScalar maxComponent() const {
23        return fX > fY ? (fX > fZ ? fX : fZ) : (fY > fZ ? fY : fZ);
24    }
25    void normalize() {
26        // Small epsilon is added to prevent division by 0.
27        SkScalar scale = SkScalarInvert(SkScalarSqrt(dot(*this)) + SK_ScalarNearlyZero);
28        fX = fX * scale;
29        fY = fY * scale;
30        fZ = fZ * scale;
31    }
32    SkPoint3 operator*(SkScalar scalar) const {
33        return SkPoint3(fX * scalar, fY * scalar, fZ * scalar);
34    }
35    SkPoint3 operator-(const SkPoint3& other) const {
36        return SkPoint3(fX - other.fX, fY - other.fY, fZ - other.fZ);
37    }
38    bool operator==(const SkPoint3& other) const {
39        return fX == other.fX && fY == other.fY && fZ == other.fZ;
40    }
41    SkScalar fX, fY, fZ;
42};
43
44class SkLight;
45
46class SK_API SkLightingImageFilter : public SkImageFilter {
47public:
48    static SkImageFilter* CreateDistantLitDiffuse(const SkPoint3& direction,
49        SkColor lightColor, SkScalar surfaceScale, SkScalar kd,
50        SkImageFilter* input = NULL, const CropRect* cropRect = NULL);
51    static SkImageFilter* CreatePointLitDiffuse(const SkPoint3& location,
52        SkColor lightColor, SkScalar surfaceScale, SkScalar kd,
53        SkImageFilter* input = NULL, const CropRect* cropRect = NULL);
54    static SkImageFilter* CreateSpotLitDiffuse(const SkPoint3& location,
55        const SkPoint3& target, SkScalar specularExponent, SkScalar cutoffAngle,
56        SkColor lightColor, SkScalar surfaceScale, SkScalar kd,
57        SkImageFilter* input = NULL, const CropRect* cropRect = NULL);
58    static SkImageFilter* CreateDistantLitSpecular(const SkPoint3& direction,
59        SkColor lightColor, SkScalar surfaceScale, SkScalar ks,
60        SkScalar shininess, SkImageFilter* input = NULL, const CropRect* cropRect = NULL);
61    static SkImageFilter* CreatePointLitSpecular(const SkPoint3& location,
62        SkColor lightColor, SkScalar surfaceScale, SkScalar ks,
63        SkScalar shininess, SkImageFilter* input = NULL, const CropRect* cropRect = NULL);
64    static SkImageFilter* CreateSpotLitSpecular(const SkPoint3& location,
65        const SkPoint3& target, SkScalar specularExponent, SkScalar cutoffAngle,
66        SkColor lightColor, SkScalar surfaceScale, SkScalar ks,
67        SkScalar shininess, SkImageFilter* input = NULL, const CropRect* cropRect = NULL);
68    ~SkLightingImageFilter();
69
70    SK_DECLARE_FLATTENABLE_REGISTRAR_GROUP()
71
72protected:
73    SkLightingImageFilter(SkLight* light,
74                          SkScalar surfaceScale,
75                          SkImageFilter* input,
76                          const CropRect* cropRect = NULL);
77    explicit SkLightingImageFilter(SkFlattenableReadBuffer& buffer);
78    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
79    const SkLight* light() const { return fLight; }
80    SkScalar surfaceScale() const { return fSurfaceScale; }
81
82private:
83    typedef SkImageFilter INHERITED;
84    SkLight* fLight;
85    SkScalar fSurfaceScale;
86};
87
88#endif
89