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
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
|
/*
* Copyright 2013 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef GrCoordTransform_DEFINED
#define GrCoordTransform_DEFINED
#include "GrProcessor.h"
#include "SkMatrix.h"
#include "GrTexture.h"
#include "GrTypes.h"
/**
* Coordinates available to GrProcessor subclasses for requesting transformations. Transformed
* coordinates are made available in the the portion of fragment shader emitted by the effect.
*/
enum GrCoordSet {
/**
* The user-space coordinates that map to the fragment being rendered. These coords account for
* any change of coordinate system done on the CPU by GrContext before rendering, and also are
* correct for draws that take explicit local coords rather than inferring them from the
* primitive's positions (e.g. drawVertices). These are usually the coords a GrProcessor wants.
*/
kLocal_GrCoordSet,
/**
* The actual vertex position. Note that GrContext may not draw using the original view matrix
* specified by the caller, as it may have transformed vertices into another space. These are
* usually not the coordinates a GrProcessor wants.
*/
kPosition_GrCoordSet
};
/**
* A class representing a linear transformation from one of the built-in coordinate sets (local or
* position). GrProcessors just define these transformations, and the framework does the rest of the
* work to make the transformed coordinates available in their fragment shader.
*/
class GrCoordTransform : SkNoncopyable {
public:
GrCoordTransform() { SkDEBUGCODE(fInProcessor = false); }
/**
* Create a transformation that maps [0, 1] to a texture's boundaries.
*/
GrCoordTransform(GrCoordSet sourceCoords, const GrTexture* texture) {
SkDEBUGCODE(fInProcessor = false);
this->reset(sourceCoords, texture);
}
/**
* Create a transformation from a matrix. The optional texture parameter is used to infer if the
* framework should internally do a y reversal to account for it being upside down by Skia's
* coord convention.
*/
GrCoordTransform(GrCoordSet sourceCoords, const SkMatrix& m, const GrTexture* texture = NULL) {
SkDEBUGCODE(fInProcessor = false);
this->reset(sourceCoords, m, texture);
}
void reset(GrCoordSet sourceCoords, const GrTexture* texture) {
SkASSERT(!fInProcessor);
SkASSERT(texture);
this->reset(sourceCoords, MakeDivByTextureWHMatrix(texture), texture);
}
void reset(GrCoordSet sourceCoords, const SkMatrix& m, const GrTexture* texture = NULL) {
SkASSERT(!fInProcessor);
fSourceCoords = sourceCoords;
fMatrix = m;
fReverseY = texture && kBottomLeft_GrSurfaceOrigin == texture->origin();
}
GrCoordTransform& operator= (const GrCoordTransform& other) {
SkASSERT(!fInProcessor);
fSourceCoords = other.fSourceCoords;
fMatrix = other.fMatrix;
fReverseY = other.fReverseY;
return *this;
}
/**
* Access the matrix for editing. Note, this must be done before adding the transform to an
* effect, since effects are immutable.
*/
SkMatrix* accessMatrix() {
SkASSERT(!fInProcessor);
return &fMatrix;
}
bool operator== (const GrCoordTransform& that) const {
return fSourceCoords == that.fSourceCoords &&
fMatrix.cheapEqualTo(that.fMatrix) &&
fReverseY == that.fReverseY;
}
bool operator!= (const GrCoordTransform& that) const { return !(*this == that); }
GrCoordSet sourceCoords() const { return fSourceCoords; }
const SkMatrix& getMatrix() const { return fMatrix; }
bool reverseY() const { return fReverseY; }
/** Useful for effects that want to insert a texture matrix that is implied by the texture
dimensions */
static inline SkMatrix MakeDivByTextureWHMatrix(const GrTexture* texture) {
SkASSERT(texture);
SkMatrix mat;
mat.setIDiv(texture->width(), texture->height());
return mat;
}
private:
GrCoordSet fSourceCoords;
SkMatrix fMatrix;
bool fReverseY;
typedef SkNoncopyable INHERITED;
#ifdef SK_DEBUG
public:
void setInProcessor() const { fInProcessor = true; }
private:
mutable bool fInProcessor;
#endif
};
#endif
|
