blob: 2e52485791f9ca6c31cd382058514c749b3f636b (
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
|
/*
* Copyright 2017 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef GrBlurredEdgeFragmentProcessor_DEFINED
#define GrBlurredEdgeFragmentProcessor_DEFINED
#include "GrFragmentProcessor.h"
/**
* Shader for managing a blurred edge for a shadow.
*
* There are two blurring modes supported: Gaussian blur function and smoothstep function.
*
* If the primitive supports an implicit distance to the edge, the radius of the blur is specified
* by r & g values of the color in 14.2 fixed point. For spot shadows, we increase the stroke width
* to set the shadow against the shape. This pad is specified by b, also in 6.2 fixed point.
*
* When not using implicit distance, then b in the input color represents the input to the
* blur function.
*
* In either case, the a value represents the max final alpha.
*/
class GrBlurredEdgeFP : public GrFragmentProcessor {
public:
enum Mode {
kGaussian_Mode,
kSmoothstep_Mode,
kLastMode = kSmoothstep_Mode
};
static const int kModeCnt = kLastMode + 1;
static sk_sp<GrFragmentProcessor> Make(Mode mode = kGaussian_Mode) {
return sk_sp<GrFragmentProcessor>(new GrBlurredEdgeFP(mode));
}
const char* name() const override { return "BlurredEdge"; }
Mode mode() const { return fMode; }
private:
GrBlurredEdgeFP(Mode mode)
: INHERITED(kNone_OptimizationFlags)
, fMode(mode) {
// enable output of distance information for shape
this->setWillUseDistanceVectorField();
this->initClassID<GrBlurredEdgeFP>();
}
GrGLSLFragmentProcessor* onCreateGLSLInstance() const override;
void onGetGLSLProcessorKey(const GrShaderCaps&, GrProcessorKeyBuilder*) const override;
bool onIsEqual(const GrFragmentProcessor&) const override;
void onComputeInvariantOutput(GrInvariantOutput* inout) const override;
GR_DECLARE_FRAGMENT_PROCESSOR_TEST;
Mode fMode;
typedef GrFragmentProcessor INHERITED;
};
#endif
|
