PySide.QtOpenGL.QGLPixelBuffer class encapsulates an OpenGL pbuffer.
Rendering into a pbuffer is normally done using full hardware acceleration. This can be significantly faster than rendering into a PySide.QtGui.QPixmap .
There are three approaches to using this class:
As of Qt 4.8, it's possible to render into a PySide.QtOpenGL.QGLPixelBuffer 使用 PySide.QtGui.QPainter in a separate thread. Note that OpenGL 2.0 or OpenGL ES 2.0 is required for this to work. Also, under X11, it's necessary to set the Qt.AA_X11InitThreads 应用程序属性。
Pbuffers are provided by the OpenGL pbuffer extension; call hasOpenGLPbuffer() to find out if the system provides pbuffers.
另请参阅
Pbuffers Example
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Constructs an OpenGL pbuffer of the given size . If no format is specified, the default format is used. If the shareWidget parameter points to a valid PySide.QtOpenGL.QGLWidget , the pbuffer will share its context with shareWidget .
If you intend to bind this pbuffer as a dynamic texture, the width and height components of size must be powers of two (e.g., 512 x 128).
这是重载函数。
Constructs an OpenGL pbuffer with the width and height . If no format is specified, the default format is used. If the shareWidget parameter points to a valid PySide.QtOpenGL.QGLWidget , the pbuffer will share its context with shareWidget .
If you intend to bind this pbuffer as a dynamic texture, the width and height components of size must be powers of two (e.g., 512 x 128).
| 参数： | fileName – unicode |
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| 返回类型： | PySide.QtOpenGL.GLuint |
这是重载函数。
Reads the DirectDrawSurface (DDS) compressed file fileName and generates a 2D GL texture from it.
相当于调用 QGLContext.bindTexture() .
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PySide.QtOpenGL.GLuint |
这是重载函数。
Generates and binds a 2D GL texture based on pixmap .
相当于调用 QGLContext.bindTexture() .
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PySide.QtOpenGL.GLuint |
Generates and binds a 2D GL texture to the current context, based on image . The generated texture id is returned and can be used in later glBindTexture() calls.
target parameter specifies the texture target.
相当于调用 QGLContext.bindTexture() .
| 参数： | texture – PySide.QtOpenGL.GLuint |
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| 返回类型： | PySide.QtCore.bool |
Binds the texture specified by texture_id to this pbuffer. Returns true on success; otherwise returns false.
The texture must be of the same size and format as the pbuffer.
To unbind the texture, call PySide.QtOpenGL.QGLPixelBuffer.releaseFromDynamicTexture() . While the texture is bound, it is updated automatically when the pbuffer contents change, eliminating the need for additional copy operations.
范例：
pbuffer QGLPixelBuffer(...)
...
pbuffer.makeCurrent()
dynamicTexture = pbuffer.generateDynamicTexture()
pbuffer.bindToDynamicTexture(dynamicTexture)
...
pbuffer.releaseFromDynamicTexture()
警告
This function uses the render_texture extension, which is currently not supported under X11. An alternative that works on all systems (including X11) is to manually copy the pbuffer contents to a texture using PySide.QtOpenGL.QGLPixelBuffer.updateDynamicTexture() .
警告
对于 PySide.QtOpenGL.QGLPixelBuffer.bindToDynamicTexture() call to succeed on the Mac OS X, the pbuffer needs a shared context, i.e. the PySide.QtOpenGL.QGLPixelBuffer must be created with a share widget.
| 参数： | texture_id – PySide.QtOpenGL.GLuint |
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Removes the texture identified by texture_id from the texture cache.
相当于调用 QGLContext.deleteTexture() .
| 返回类型： | PySide.QtCore.bool |
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Makes no context the current OpenGL context. Returns true on success; otherwise returns false.
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Draws the given texture, textureId , at the given point in OpenGL model space. The textureTarget parameter should be a 2D texture target.
Equivalent to the corresponding QGLContext.drawTexture() .
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Draws the given texture, textureId , to the given target rectangle, target , in OpenGL model space. The textureTarget should be a 2D texture target.
Equivalent to the corresponding QGLContext.drawTexture() .
| 返回类型： | PySide.QtOpenGL.QGLFormat |
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Returns the format of the pbuffer. The format may be different from the one that was requested.
| 返回类型： | PySide.QtOpenGL.GLuint |
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| 返回类型： | PySide.QtCore.Qt::HANDLE |
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Returns the native pbuffer handle.
| 返回类型： | PySide.QtCore.bool |
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Returns true if the OpenGL pbuffer extension is present on this system; otherwise returns false.
| 返回类型： | PySide.QtCore.bool |
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Returns true if this pbuffer is valid; otherwise returns false.
| 返回类型： | PySide.QtCore.bool |
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Makes this pbuffer the current OpenGL rendering context. Returns true on success; otherwise returns false.
Releases the pbuffer from any previously bound texture.
| 返回类型： | PySide.QtCore.QSize |
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Returns the size of the pbuffer.
| 返回类型： | PySide.QtGui.QImage |
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Returns the contents of the pbuffer as a PySide.QtGui.QImage .
| 参数： | texture_id – PySide.QtOpenGL.GLuint |
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Copies the pbuffer contents into the texture specified with texture_id .
The texture must be of the same size and format as the pbuffer.
范例：
pbuffer QGLPixelBuffer(...)
...
pbuffer.makeCurrent()
dynamicTexture = pbuffer.generateDynamicTexture()
...
pbuffer.updateDynamicTexture(dynamicTexture)
An alternative on Windows and Mac OS X systems that support the render_texture extension is to use PySide.QtOpenGL.QGLPixelBuffer.bindToDynamicTexture() to get dynamic updates of the texture.