[comp.windows.interviews] How to check that Bitmap is valid?

linton@marktwain.rad.sgi.com (Mark Linton) (04/15/91)

In article <9104121357.AA03653@control.lth.se>, dag@CONTROL.LTH.SE (Dag Bruck) writes:
|> Environment: InterViews 2.6 with patches, Sun-4, SunOS 4.1.1, Cfront 2.1.
|> 
|> I create bitmap objects using the constructor
|> 
|> 	Bitmap(const char* filename);
|> 
|> However, if the given filename doesn't refer to a valid bitmap file,
|> I get some strange X protocol error later on.
|> 
|> QUESTION: How do I check that the created Bitmap object really refers
|> to a valid bitmap?

This is a bug.  3.0 no longer has that constructor, but instead has a static member
function "open" that returns a Bitmap* if the file is found or nil otherwise.

Tom.Emerson@UVM.EDU (Tom Emerson) (04/16/91)

>>>>> On Fri, 12 Apr 91 15:57:09 +0200, Dag Bruck <dag@control.lth.se> said:

Dag> Environment: InterViews 2.6 with patches, Sun-4, SunOS 4.1.1,
Dag> Cfront 2.1.

Dag> I create bitmap objects using the constructor

Dag> 	Bitmap(const char* filename);

Dag> However, if the given filename doesn't refer to a valid bitmap file,
Dag> I get some strange X protocol error later on.

Dag> QUESTION: How do I check that the created Bitmap object really refers
Dag> to a valid bitmap?

The way I do it is to #include the bitmap sources and then use the
bitmap(void* data, int width, int height, int x0, int y0) with the
information supplied with the bitmap.

Thomas


--
                                     Thomas Emerson
________________   Student Systems Programmer - EMBA Computer Facility
 /  /_) /_  /_                    University of Vermont
/  / \ /__ /__                     tree@newton.uvm.edu 
     "It's a pity the universe doesn't use segmented architecture
		       with a protected mode."           --- Rick Cook