Re: modifying points of a polyline

[Stefan Kost <ensonic hora-obscura de>]

Am 18.12.2009 01:27, schrieb Damon Chaplin:
> 
> On Fri, 2009-12-18 at 00:10 +0200, Stefan Kost wrote:
>> hi,
>>
>> I have a polyline initialy created as
>>       item->citem = goo_canvas_polyline_new (self->priv->canvas_root, FALSE, 2,
>>         item->ns->x, item->ns->y,
>>         item->ne->x, item->ne->y,
>>         "stroke-color", "red",
>>         "line-width", 1.0,
>>         NULL);
>>
>> later on the coorinates change. Is this the way to update them?
>>
>>       GooCanvasPoints *points;
>>       // modify the points
>>       g_object_get (item->citem, "points", &points, NULL);
>>       points->coords[0]=item->ns->x;
>>       points->coords[1]=item->ns->y;
>>       points->coords[2]=item->ne->x;
>>       points->coords[3]=item->ne->y;
>>       g_object_set (item->citem, "points", points, NULL);
>>       goo_canvas_points_unref (points);
> 
> Yes, I think so. Does it work OK?
> 
> Damon
> 

I experiment with soem live-updated graph display. The lines are quite wrong
right now. But then I am not sure if they are properly redraws. If I understood
right, goocanvas updates in a idle-callback. That could be a problem, as my app
receives logdata from a sockets and emits signals for log-events. Those
log-events cause graph changes. The graphs is not changing very smoothly. Is
there any way to force a redraw (if only for debugging it right now)?

Stefan