573687 - Radial gradients with small radii are not clamped correctly

Status: RESOLVED FIXED

(Core :: SVG, defect)

Description

[Robert Longson [:longsonr]]

Attachment: patch

We need to take an absolute value off to ensure different cairo fractions, not an amount we multiply by the radius because this will fail if the radius is significantly less than 1.

Comment 1

[Robert Longson [:longsonr]]

See also http://dev.w3.org/SVG/profiles/1.1F2/test/harness/htmlObject/pservers-grad-21-b.html

Comment 2

[Jonathan Watt [:jwatt]]

Does what we get here depend on the CTM of the element being filled? In other words do you know if cairo could end up rounding the value due to converting to absolute coordinates?

Comment 3

[Robert Longson [:longsonr]]

The problem is here:
http://mxr.mozilla.org/mozilla-central/source/gfx/cairo/cairo/src/cairo-pattern.c#444

The call stack is

new gfxPattern
cairo_pattern_create_radial
_cairo_pattern_innit_radial

And the arguments are passed through unchanged to that point.

There is a cairo_pattern_transform but it looks like when this is applied in _cairo_pattern_get_extents it's working in doubles.

So on the whole it looks OK to me.

Comment 4

[Robert Longson [:longsonr]]

btw I should have used NS_MAX rather than PR_MAX as it seems PR_MAX is deprecated now. I can fix that on check in.

Comment 5

[Jonathan Watt [:jwatt]]

Comment on attachment 452999 [details] [diff] [review]
patch

Okay, great. Thanks for checking.

Comment 6

[Robert Longson [:longsonr]]

pushed http://hg.mozilla.org/mozilla-central/rev/c5c14a904af4