Bug 42419

Summary:	Failed to create sub-surface by cairo_surface_create_for_rectangle()
Product:	cairo	Reporter:	Seongwon Cho <seongwon79>
Component:	image backend	Assignee:	Carl Worth <cworth>
Status:	RESOLVED MOVED	QA Contact:	cairo-bugs mailing list <cairo-bugs>
Severity:	critical
Priority:	highest
Version:	1.10.3
Hardware:	x86 (IA32)
OS:	Linux (All)
URL:	https://bugzilla.samba.org/show_bug.cgi?id=11495
Whiteboard:
i915 platform:		i915 features:

Description Seongwon Cho 2011-10-31 04:41:09 UTC

Hi,

When I make sub-surface by cairo_surface_create_for_rectangle()
I got nil surface on special use case.

inside of cairo_surface_create_for_rectangle(cairo_surface_t *target, double x, double y, double width, double height)
cairo changes argument ,double to integer, like below.

    surface->extents.x = ceil (x);
    surface->extents.y = ceil (y);
    surface->extents.width = floor (x + width) - surface->extents.x;
    surface->extents.height = floor (y + height) - surface->extents.y;

But if I put the x = 0.2, width = 0.7 on cairo_surface_create_for_rectangle() the width of surface is assigned by -1.

    surface->extents.x = 1; //ceil(0.2) == 1
    surface->extents.width = -1; //floor(0.2+0.7) - 1 == 0 - 1 == -1

It looks like a cairo's bug

Thanks

Comment 1 GitLab Migration User 2018-08-25 13:50:44 UTC

-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

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