Usage and precautions of transform

1. Function:

1) Transform can control panning, scaling, and rotation.

2) The methods in transform are mainly divided into two types: with make and without make.

3) The method with make is changed mainly based on the initial state of the control, so it is usually only changed once.

4) The method without make needs to pass in a transform, and the control is changed according to the incoming transform, which is usually the transform of the control itself.

5) Transform and frame must not be mixed, otherwise unexpected problems will occur.

2. Use of methods:

1) A panning method with make, () the previous value is the distance moved on the x-axis, and the last value is the distance traveled on the y-axis. Control can only be moved once based on the original state.

2) without make translation method, generally need to pass in their own transform, can be changed multiple positions.

3) with Make zoom method, can only do one zoom, () The number is to represent the scale of the number 1 represents 100% less than 1 to zoom out greater than 1 to zoom in.

4) The scaling method without make can be scaled multiple times on the basis of the incoming transform.

5) with make rotation method, can only rotate once, the default is to the right clockwise rotation, positive, negative for the right rotation,-m_pi_4 to the right 45 degrees, and so on.

6) The rotation method without make can be rotated multiple times.

3.transform and bounds and frame of the differences and mixed development considerations:

Usage and precautions of transform