i understand that if i wanted to make a sprite i would have to use code that looked like this.


Code:

and so on and so forth. but if i wanted to move it around and display it what exactly would i do because 28 days got me confused and asmguru didnt even explain it.

Well, first you need to understand the basic components you need:

1>> a sprite to move around
2>> a routine to draw it at x,y
3>> a routine to erase it at x,y
4>> a routine to check keys
5>> a routine to inc/dec x and y based on keys.

Luckily, as I'm sure you know, parts (2) and (3) can use the same XORed sprite routine, such as the one Ion provides.

how exactly would i go about doing parts (2) and (3). and the xor,and,or

those things confused me a lot so i think that might be a part of my problem. as for the other parts i basicaly know how to do them.

OK, let's discuss bitwise AND, OR, and XOR then. For all these examples, let's assume we have two variables, a and b.

a = %11010010
b = %10111011

a AND b
When you bitwise AND two sets of bits together, only the bits where both are 1 become one. If one or more bits are 0, it's zero. So,

a AND b = %11010010 AND %10111011 = %10010010

a OR b
When you bitwise OR two sets of bits together, any bit where either bit is 1 become one. It's only zero when both are zero. So,

a OR b = %11010010 OR %10111011 = %11111011

a XOR b
XOR is the strangest operator of the bunch. With XOR, the output bit is only 1 if exactly one of the input bits is one and the other is zero. If both are zero, or both are one, the output is zero. Therefore:

a XOR b = %11010010 XOR %10111011 = %01101001

so with knowledge of the and,or, xor

how exactly would i do parts (2),(3),(5)

i know with five i would have to do something like


Code:


so the parts two and three are the only other problems

OK. When you XOR something to the screen, it draws it. But if you XOR the exact same sprite OVER that sprite, it erases it! So just XOR before the key loop to draw, then loop until you get a key, then XOR again to erase, then change the coordinates, and start over!

okay sounds easy enough. if i wanted to xor the sprite what would i do though. would this work.


Code:


also if i wanted the sprite to be larger wouldnt i have to use .dw

Come on, this is not BASIC. I'm not going to list out the routine you need to make this work, but I will tell you what it will involve and rely on you to make the code because you seem to take the easy/short way out on everything (I say this because the routine and an explanation thereof is in asmin28days and you must have just skimmed over it and expected us to explain it).

You need to basically copy the data from where the sprite is located to the graph buffer (called PlotsScreen). You can Xor it with what is there already, OR it with what is there already or do whatever other boolean logic to it, but fundamentally, all you are doing is copying the data to the PlotsScreen (which is a 768byte section of memory, each bit representing a pixel (1 on 0 off)). Now, the bit shifting and finding of where to store this sprite to in PlotsScreen I will leave up to you to figure out. I'm not about to lay out the entire routine when you are fully capable of creating it yourself.

If you do have specific questions about a certain part of the routine and have given a valid attempt yourself (not just writing xor), then we will be more than happy to help.

Maybe some code will help him out. This is a little program I made when I was first learning Asm. It's a mirage program and uses Ion libs for sprites. Note that it is for the 83+, so you'll have to change some things for the 83.

Code:

On a side note, did the tag buttons always look like that? They look cool.

No, I reskinned a few of the forum features recently.
I think that that could be simplified a ton. I'd post up the Doors CS mouse routine, but that would just confuse you more due to all the dynamic cursor stuff.

okay i guess i will just go through and try to create it myself. hopefully i can do it. the only thing i need to know is how exactly do i use the xor command like do i:


Code:


or:


Code:

No no no. You can't just xor all at once. You can only xor one byte with another byte at a time in z80 asm. To do this, use ionPutSprite, which XORs a sprite with the graphbuffer. It does all the alignment and everything so you only need to worry about keeping the coordinates up to date.

Like I said before there's A TON MORE TO IT THAN THAT!!! But, since you insist, xor's syntax is as follows:


Code:
where n is a number between 0 and 255 or an eight bit register. It will xor the contents of n with the accumulator. It can also be used for a quicker/smaller way to ld a,0 by doing xor a.

where exactly can i find ionputsprite. and will it be an ion program if i use ionputsprite.

If you want to include it yourself, get the Ion source code at ticalc.org. If you're programming for Ion, DCS, or a similar shell, you can just do
Code:
or
Code:
depending on the shell, as long as you have the correct include file in the header.

You would have to use Ion to be able to use the library within Ion. Personally, I think you should be able to make the display routine yourself before you use ion's library. Depending on libraries to do all the hard and messy stuff for you sounds a little bit like BASIC?

Edit: Kerm keeps beating me with the replies. He's a machine.

i guess i will forget the libs for now since i am not that experienced. and i guess i will just experiment until i get it right.

<off topic>Do games go faster in ion or any other shell?

Re: libs: fair enough
Re: speed: all assembly programs, shell or not, run at the same speed with a few minor exceptions for the 83+SE and 84+SE.
Re: Chip: ha! pwned.

allright now i know this might make you guys frustrated or mad . but i know how to create the sprite but putting it on the screen is super confusing and i went and read over asm lesson a couple more times and i am still confused. and chipmaster i am not asking for the code for it i am just asking how in the world would i do it.

Go to ticalc.org and look in the ASM source directory. There are some beginner, easy programs w/ source there to show you basic things like what you are asking