Re: About x_draw_xwidget_glyph_string

[Eli Zaretskii]

> Date: Mon, 25 Jan 2016 11:07:16 +0900
> From: YAMAMOTO Mitsuharu <address@hidden>
> 
> 2. Comment on clipping.
> 
>    578          /* Calculate clipping, which is used for all manner of 
> onscreen
>    579             xwidget views.  Each widget border can get clipped by 
> other emacs
>    580             objects so there are four clipping variables.  */
>    581          clip_right =
>    582            min (xww->width,
>    583                 WINDOW_RIGHT_EDGE_X (s->w) - x -
>    584                 WINDOW_RIGHT_SCROLL_BAR_AREA_WIDTH (s->w) -
>    585                 WINDOW_RIGHT_FRINGE_WIDTH (s->w));
>    586          clip_left =
>    587            max (0,
>    588                 WINDOW_LEFT_EDGE_X (s->w) - x +
>    589                 WINDOW_LEFT_SCROLL_BAR_AREA_WIDTH (s->w) +
>    590                 WINDOW_LEFT_FRINGE_WIDTH (s->w));
>    591        
>    592          clip_bottom =
>    593            min (xww->height,
>    594                 WINDOW_BOTTOM_EDGE_Y (s->w) - WINDOW_MODE_LINE_HEIGHT 
> (s->w) - y);
>    595          clip_top = max (0, WINDOW_TOP_EDGE_Y (s->w) - y);
> 
> I think the calculation of clipping should use the function window_box
> rather than manual calculation with various window macros.  Otherwise,
> xwidget views will cover horizontal scroll bars, for example.

I agree.

Thanks.