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39
40#ifndef QT3DRENDER_RENDER_STATEVARIANT_P_H
41#define QT3DRENDER_RENDER_STATEVARIANT_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists for the convenience
48// of other Qt classes. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <Qt3DRender/private/renderstates_p.h>
55
56QT_BEGIN_NAMESPACE
57
58namespace Qt3DRender {
59namespace Render {
60
61struct Q_3DRENDERSHARED_PRIVATE_EXPORT StateVariant
62{
63 StateMask type;
64
65 union u_Data {
66 BlendEquationArguments blendEquationArguments;
67 BlendEquation blendEquation;
68 AlphaFunc alphaFunc;
69 MSAAEnabled msaaEnabled;
70 DepthRange depthRange;
71 DepthTest depthTest;
72 NoDepthMask noDepthMask;
73 CullFace cullFace;
74 FrontFace frontFace;
75 Dithering dithering;
76 ScissorTest scissorTest;
77 StencilTest stencilTest;
78 AlphaCoverage alphaCoverage;
79 PointSize pointSize;
80 PolygonOffset polygonOffset;
81 ColorMask colorMask;
82 ClipPlane clipPlane;
83 SeamlessCubemap seamlessCubemap;
84 StencilOp stencilOp;
85 StencilMask stencilMask;
86 LineWidth lineWidth;
87
88 u_Data()
89 {
90 // Assumes the above types don't need to have their ctor called
91 memset(s: static_cast<void *>(this), c: 0, n: sizeof(u_Data));
92 }
93
94 u_Data(const u_Data &other)
95 {
96 memcpy(dest: static_cast<void *>(this), src: static_cast<const void *>(&other), n: sizeof(u_Data));
97 }
98
99 u_Data& operator=(const u_Data &other)
100 {
101 memcpy(dest: static_cast<void *>(this), src: static_cast<const void *>(&other), n: sizeof(u_Data));
102 return *this;
103 }
104
105 ~u_Data()
106 {
107 // Assumes the above types don't need to have their dtor called
108 }
109 } data;
110
111 template<class State, typename ... Args>
112 static StateVariant createState(Args... values)
113 {
114 State state;
115 state.set(values...);
116 return StateVariant::fromValue(state);
117 }
118
119 template<typename GenericState>
120 static StateVariant fromValue(const GenericState &state)
121 {
122 StateVariant v;
123 v.type = GenericState::type();
124 // all union members start at the same memory address
125 // so we can just write into whichever we want
126 memcpy(dest: static_cast<void *>(&v.data), src: static_cast<const void *>(&state), n: sizeof(state));
127 return v;
128 }
129
130 RenderStateImpl *state();
131 const RenderStateImpl *constState() const;
132
133 bool operator ==(const StateVariant &other) const;
134 bool operator !=(const StateVariant &other) const;
135};
136
137} // namespace Render
138} // namespace Qt3DRender
139
140QT_END_NAMESPACE
141
142#endif // QT3DRENDER_RENDER_STATEVARIANT_P_H
143

source code of qt3d/src/render/renderstates/statevariant_p.h