Re: A86: Re: Sprites (More)

To: assembly-86@lists.ticalc.org
Subject: Re: A86: Re: Sprites (More)
From: Smiths <smithrh@esper.com>
Date: Mon, 04 Jan 1999 15:38:35 -0500
Delivered-To: assembly-86-outgoing@towerguard.unix.edu.sollentuna.se
In-Reply-To: <005b01be36bf$ff402580$7046dacd@computername>
Reply-To: assembly-86@lists.ticalc.org


I understand what sprite masking does and is, but how do I use it in code?

Nat Sith
smithrh@esper.com
>
>>
>>More questions.
>>
>> 1)  What is the advantage to using masked sprites or vice versa?
>
>With sprite masking, you can make part of a sprite transparent, so that the
>background behind that pixel isn't erased.
>
>> 2)  What is the difference in the PutSprite routines?  I have seen them
>AND'd
>>and XOR'd, but I guess I don't understand the difference.
>
>XOR'ing is usually the best way to go.  It will clear a pixel if there is
>already a pixel set where another set pixel is being XOR'ed to.  Like:
>    ld bc,0101
>    ld hl,sprite
>    call _PutSprite_that_uses_xor
>    ;sprite is now pasted to the screen
>    call _PutSprite_that_uses_xor
>    ;sprite has now been erased from the screen
>Hope this helps some,
>_________
>JBrett
>tbarwick@esn.net
>ICQ UIN: 20607010
>AIM: BarwickBJ
>http://ww2.esn.net/~tbarwick
>Plexus Publishing member
>ACZ member

References:

A86: Re: Sprites (More)

From: "JBrett" <tbarwick@esn.net>