51d40d7e9b
This corrects the mismatch between using floats for internal storage and qreal in the API of QVector*D which leads to lots of implicit casts between double and float. This change also stops users from being surprised by the loss of precision when using these classes on desktop platforms and removes the need for the private constructors taking a dummy int as the final argument. The QMatrix4x4 and QQuaternion classes have been changed to use float for their internal storage since these are meant to be used in conjunction with the QVector*D classes. This is to prevent unexpected loss of precision and to improve performance. The on-disk format has also been changed from double to float thereby reducing the storage required when streaming vectors and matrices. This is potentially a large saving when working with complex 3D meshes etc. This also has a significant performance improvement when passing matrices to QOpenGLShaderProgram (and QGLShaderProgram) as we no longer have to iterate and convert the data to floats. This is an operation that could easily be needed many times per frame. This change also opens the door for further optimisations of these classes to be implemented by using SIMD intrinsics. This needs to be applied in conjunction with https://codereview.qt-project.org/#change,33548 Task-number: QTBUG-21035 Task-number: QTBUG-20661 Change-Id: I9321b06040ffb93ae1cbd72fd2013267ac901b2e Reviewed-by: Lars Knoll <lars.knoll@nokia.com> |
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| dbus | ||
| embedded | ||
| gestures | ||
| gui | ||
| ipc | ||
| ja_JP/linguist/hellotr | ||
| linguist | ||
| network | ||
| opengl | ||
| qmake | ||
| qpa | ||
| qtconcurrent | ||
| qtestlib | ||
| sql | ||
| threads | ||
| tools | ||
| touch | ||
| tutorials | ||
| webkit/webkit-guide | ||
| widgets | ||
| xml | ||
| examples.pro | ||
| README | ||
Qt is supplied with a number of example applications that have been written to provide developers with examples of the Qt API in use, highlight good programming practice, and showcase features found in each of Qt's core technologies. Documentation for examples can be found in the Examples section of the Qt documentation.