Add setDisplaySize method in BitmapText

[rexrainbow]

Please do not update the README or Change Log, we will do this when we merge your PR.

This PR (delete as applicable)

• Adds a new feature

Describe the changes below:

Since BitmapText does not have original size, I set scaleX, scaleY to 1 to get original size,
then calculate new scaleX, scaleY by displayWidth, displayHeight.

[photonstorm]

Does it fix something to add this? Or is it just a feature?

[rexrainbow]

Since displayWidth, displayHeight properties does not have setter, I thought it is a new feature.

Because that BitmapText has scaleX, scaleY properties, it can have setter of displayWidth, displayHeight propertie.
But BitmapText does not store original size (size when scale is 1) directly, I have to get this original size first. This solution is not straightforward I agree.

[photonstorm]

I think I'd rather just store the original size somewhere and use that. Although I guess it will need resetting every time you change the font size, for example.

[rexrainbow]

I think I'd rather just store the original size somewhere and use that. Although I guess it will need resetting every time you change the font size, for example.

It is a better solution.

[zekeatchan]

Hi @rexrainbow. Thanks for the PR. We have merged it with the master branch. It will be part of the next release. Do test it out and let us know if you encounter any issues.