1/*
2 * Copyright 2016 Google Inc.
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 GrShaderVar_DEFINED
9#define GrShaderVar_DEFINED
10
11#include "include/core/SkString.h"
12#include "include/private/GrTypesPriv.h"
13
14class GrShaderCaps;
15
16/**
17 * Represents a variable in a shader
18 */
19class GrShaderVar {
20public:
21 enum class TypeModifier {
22 None,
23 Out,
24 In,
25 InOut,
26 Uniform,
27 };
28
29 /** Values for array count that have special meaning. We allow 1-sized arrays. */
30 enum {
31 kNonArray = 0, // not an array
32 kUnsizedArray = -1, // an unsized array (declared with [])
33 };
34
35 /** Defaults to a void with no type modifier or layout qualifier. */
36 GrShaderVar()
37 : fType(kVoid_GrSLType)
38 , fTypeModifier(TypeModifier::None)
39 , fCount(kNonArray) {}
40
41 GrShaderVar(SkString name, GrSLType type, int arrayCount = kNonArray)
42 : fType(type)
43 , fTypeModifier(TypeModifier::None)
44 , fCount(arrayCount)
45 , fName(std::move(name)) {}
46 GrShaderVar(const char* name, GrSLType type, int arrayCount = kNonArray)
47 : GrShaderVar(SkString(name), type, arrayCount) {}
48
49 GrShaderVar(SkString name, GrSLType type, TypeModifier typeModifier)
50 : fType(type)
51 , fTypeModifier(typeModifier)
52 , fCount(kNonArray)
53 , fName(std::move(name)) {}
54 GrShaderVar(const char* name, GrSLType type, TypeModifier typeModifier)
55 : GrShaderVar(SkString(name), type, typeModifier) {}
56
57 GrShaderVar(SkString name, GrSLType type, TypeModifier typeModifier, int arrayCount)
58 : fType(type)
59 , fTypeModifier(typeModifier)
60 , fCount(arrayCount)
61 , fName(std::move(name)) {}
62
63 GrShaderVar(SkString name, GrSLType type, TypeModifier typeModifier, int arrayCount,
64 SkString layoutQualifier, SkString extraModifier)
65 : fType(type)
66 , fTypeModifier(typeModifier)
67 , fCount(arrayCount)
68 , fName(std::move(name))
69 , fLayoutQualifier(std::move(layoutQualifier))
70 , fExtraModifiers(std::move(extraModifier)) {}
71
72 GrShaderVar(const GrShaderVar&) = default;
73 GrShaderVar& operator=(const GrShaderVar&) = default;
74 GrShaderVar(GrShaderVar&&) = default;
75 GrShaderVar& operator=(GrShaderVar&&) = default;
76
77 /** Sets as a non-array. */
78 void set(GrSLType type,
79 const char* name) {
80 SkASSERT(kVoid_GrSLType != type);
81 fType = type;
82 fName = name;
83 }
84
85 /** Is the var an array. */
86 bool isArray() const { return kNonArray != fCount; }
87
88 /** Is this an unsized array, (i.e. declared with []). */
89 bool isUnsizedArray() const { return kUnsizedArray == fCount; }
90
91 /** Get the array length. */
92 int getArrayCount() const { return fCount; }
93
94 /** Get the name. */
95 const SkString& getName() const { return fName; }
96
97 /** Shortcut for this->getName().c_str(); */
98 const char* c_str() const { return this->getName().c_str(); }
99
100 /** Get the type. */
101 GrSLType getType() const { return fType; }
102
103 TypeModifier getTypeModifier() const { return fTypeModifier; }
104 void setTypeModifier(TypeModifier type) { fTypeModifier = type; }
105
106 /** Appends to the layout qualifier. */
107 void addLayoutQualifier(const char* layoutQualifier) {
108 if (!layoutQualifier || !strlen(layoutQualifier)) {
109 return;
110 }
111 if (fLayoutQualifier.isEmpty()) {
112 fLayoutQualifier = layoutQualifier;
113 } else {
114 fLayoutQualifier.appendf(", %s", layoutQualifier);
115 }
116 }
117
118 /** Appends to the modifiers. */
119 void addModifier(const char* modifier) {
120 if (!modifier || !strlen(modifier)) {
121 return;
122 }
123 if (fExtraModifiers.isEmpty()) {
124 fExtraModifiers = modifier;
125 } else {
126 fExtraModifiers.appendf(" %s", modifier);
127 }
128 }
129
130 /** Write a declaration of this variable to out. */
131 void appendDecl(const GrShaderCaps*, SkString* out) const;
132
133private:
134 GrSLType fType;
135 TypeModifier fTypeModifier;
136 int fCount;
137
138 SkString fName;
139 SkString fLayoutQualifier;
140 SkString fExtraModifiers;
141};
142
143#endif
144