GetDimensions precision

[kwhopper]

Implementation of #179...

Round SvgExtensions.Transforms.GetDimensions return value to three decimal places. Otherwise, non-integer viewbox dimensions lose precision. This can cause subtle left/top shifts in raster output.

The standard data type for viewbox dimensions is a "number" and can be decimal:
https://developer.mozilla.org/en-US/docs/Web/SVG/Content_type#number

SKSize members and all relevant local variables are floats so this should cause no issues. The only unsure part is whether "3" is too arbitrary; a very large ViewBox could have four significant integer figures so a case could be made for "4" instead.

[wieslawsoltes]

Implementation of #179...

Round SvgExtensions.Transforms.GetDimensions return value to three decimal places. Otherwise, non-integer viewbox dimensions lose precision. This can cause subtle left/top shifts in raster output.

The standard data type for viewbox dimensions is a "number" and can be decimal: https://developer.mozilla.org/en-US/docs/Web/SVG/Content_type#number

SKSize members and all relevant local variables are floats so this should cause no issues. The only unsure part is whether "3" is too arbitrary; a very large ViewBox could have four significant integer figures so a case could be made for "4" instead.

And why 4 is not too arbitrary. If it can be decimal we should use decimal precision everywhere.

[kwhopper]

And why 4 is not too arbitrary. If it can be decimal we should use decimal precision everywhere.

I believe in the spec it says "real" or "decimal" number in a generic sense so I'm not sure of the best practice for scale in this case. But one way to avoid any arbitrary rounding is to not use Math.Round at all for these values?