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39
40#include "qnodraw.h"
41
42QT_BEGIN_NAMESPACE
43
44namespace Qt3DRender {
45
46/*!
47 \class Qt3DRender::QNoDraw
48 \inmodule Qt3DRender
49
50 \brief When a Qt3DRender::QNoDraw node is present in a FrameGraph branch, this
51 prevents the renderer from rendering any primitive.
52
53 Qt3DRender::QNoDraw should be used when the FrameGraph needs to set up some render
54 states or clear some buffers without requiring any mesh to be drawn. It has
55 the same effect as having a Qt3DRender::QRenderPassFilter that matches none of
56 available Qt3DRender::QRenderPass instances of the scene without the overhead cost
57 of actually performing the filtering.
58
59 When disabled, a Qt3DRender::QNoDraw node won't prevent the scene from
60 being rendered. Toggling the enabled property is therefore a way to make a
61 Qt3DRender::QNoDraw active or inactive.
62
63 Qt3DRender::QNoDraw is usually used as a child of a
64 Qt3DRendeR::QClearBuffers node to prevent from drawing the scene when there
65 are multiple render passes.
66
67 \code
68 Qt3DRender::QViewport *viewport = new Qt3DRender::QViewport();
69 Qt3DRender::QCameraSelector *cameraSelector = new Qt3DRender::QCameraSelector(viewport);
70
71 Qt3DRender::QClearBuffers *clearBuffers = new Qt3DRender::QClearBuffers(cameraSelector);
72 clearBuffers->setBuffers(Qt3DRender::QClearBuffers::ColorDepthBuffer);
73
74 Qt3DRender::QNoDraw *noDraw = new Qt3DRender::QNoDraw(clearBuffers);
75
76 Qt3DRender::QRenderPassFilter *mainPass = new Qt3DRender::QRenderPassFilter(cameraSelector);
77 ....
78 Qt3DRender::QRenderPassFilter *previewPass = new Qt3DRender::QRenderPassFilter(cameraSelector);
79 ....
80 \endcode
81
82 \since 5.5
83 */
84
85/*!
86 \qmltype NoDraw
87 \instantiates Qt3DRender::QNoDraw
88 \inherits FrameGraphNode
89 \inqmlmodule Qt3D.Render
90 \since 5.5
91 \brief When a NoDraw node is present in a FrameGraph branch, this
92 prevents the renderer from rendering any primitive.
93
94 NoDraw should be used when the FrameGraph needs to set up some render
95 states or clear some buffers without requiring any mesh to be drawn. It has
96 the same effect as having a Qt3DRender::QRenderPassFilter that matches none
97 of available Qt3DRender::QRenderPass instances of the scene without the
98 overhead cost of actually performing the filtering.
99
100 When disabled, a NoDraw node won't prevent the scene from being rendered.
101 Toggling the enabled property is therefore a way to make a NoDraw active or
102 inactive.
103
104 NoDraw is usually used as a child of a ClearBuffers node to prevent from
105 drawing the scene when there are multiple render passes.
106
107 \code
108
109 Viewport {
110 CameraSelector {
111 ClearBuffers {
112 buffers: ClearBuffers.ColorDepthBuffer
113 NoDraw { } // Prevents from drawing anything
114 }
115 RenderPassFilter {
116 ...
117 }
118 RenderPassFilter {
119 ...
120 }
121 }
122 }
123
124 \endcode
125*/
126
127/*!
128 The constructor creates an instance with the specified \a parent.
129 */
130QNoDraw::QNoDraw(QNode *parent)
131 : QFrameGraphNode(parent)
132{
133}
134
135/*! \internal */
136QNoDraw::~QNoDraw()
137{
138}
139
140} // namespace Qt3DRender
141
142QT_END_NAMESPACE
143

source code of qt3d/src/render/framegraph/qnodraw.cpp