03060: prescaling is costly

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
03060	Graphics	Trivial	Always	Mar 22, 2009, 17:07	Mar 23, 2009, 01:06

Tester	AndersH	View Status	Public	Platform	MAME (Official Binary)
Assigned To		Resolution	Invalid report	OS
Status [?]	Closed			Driver
Version	0.130	Fixed in Version		Build
		Fixed in Git Commit		Github Pull Request #

Summary	03060: prescaling is costly
Description	Warning: performance whining follows. Reported for the record. In all video options, there is a really heavy performance penalty as soon as the prescaling in use is larger than 1x1. It seems the prescaling has an inefficient implementation. (Some other emulators manage to do this with minimal performance cost.)
Steps To Reproduce
Additional Information	I almost apologize for reporting this. I do not expect anyone to "fix it", of course. But then again, someone might be interested in improving it.
Github Commit

Flags
Regression Version
Affected Sets / Systems

Attached Files

No.04033 Tafoid Administrator Mar 23, 2009, 01:06 edited on: Mar 23, 2009, 01:07	Quote from windows.txt in the DOCS folder: -prescale <amount> Controls the size of the screen images when they are passed off to the graphics system for scaling. At the minimum setting of 1, the screen is rendered at its original resolution before being scaled. At higher settings, the screen is expanded by a factor of <amount> before being scaled. With -video ddraw or -video d3d, this produces a less blurry image at the expense of some speed. In -video ddraw mode, this also increases the effective resolution of non-screen elements such as artwork and fonts. The default is 1. In short .. execution speed should be expected to be taken up by preforming this on all video output. No Bug.

No.04033

Tafoid

Administrator

Mar 23, 2009, 01:06

edited on: Mar 23, 2009, 01:07

Quote from windows.txt in the DOCS folder:

-prescale <amount>

Controls the size of the screen images when they are passed off to the
graphics system for scaling. At the minimum setting of 1, the screen
is rendered at its original resolution before being scaled. At higher
settings, the screen is expanded by a factor of <amount> before being
scaled. With -video ddraw or -video d3d, this produces a less blurry
image at the expense of some speed. In -video ddraw mode, this also
increases the effective resolution of non-screen elements such as
artwork and fonts. The default is 1.

In short .. execution speed should be expected to be taken up by preforming this on all video output. No Bug.