Blitz Basic Questions

[E-Penguin]

In 15.16 binary....

 
2.9 is
10.1110011001100110

2.89999 is
10.1110011001100110


2.900001 is also 
10.1110011001100110

It's not possible to express 0.9 exactly as a binary fraction.

[peceha]

It means I just have to throw away my brilliant idea and find another solution.
I wanted to use only one number to keep ID of a cell + direction (direction was supposed to be after a comma - a number from numeric keyboard layout).

Now I'm going to multiple direction number by 1000 and add to cell's ID (which is always less then 1000).

Thanks

[idrougge]

Originally Posted by E-Penguin

Am I relying too much on the processor? My Plan B is to draw to a bitmap, cut out shapes and then QBlit those, but, surely, the 2d drawing functions should be able to handle more than 6 polygons? Any 3d game must be doing more than that, and I'm not dealing with a z-axis at all.

Check the original examples directory, it has some polygon examples.

[E-Penguin]

Originally Posted by peceha

Now I'm going to multiple direction number by 1000 and add to cell's ID (which is always less then 1000).

The 68000 has no hardware multiplier (afaik), and no hardware divider. If you really wanted to pack data in, you'd be better off doing something with bit shifts and bit masks.

Eg, if your ID is always <1000, you can use the first 10 bits of a 16-bit word (up to 1024), and the remaining 6 bits (64) as other stuff.

Then:
combo_word = (direction LSL 10) | id
id = combo_word & $03FF
direction = combo_word LSR 10

Although, frankly, you're probably better off creating a NewType with two members.

[peceha]

I think you are right - I'll use a NewType then.

[peceha]

Hi
is there a way to make a variable global?
I would like to avoid "SHARED" statements inside all the procedures.

Thanks

[idrougge]

Originally Posted by E-Penguin

The 68000 has no hardware multiplier (afaik), and no hardware divider. If you really wanted to pack data in, you'd be better off doing something with bit shifts and bit masks.

combo_word = (direction LSL 10) | id
id = combo_word & $03FF
direction = combo_word LSR 10

Note that long shifts on the plain 68000 also cost quite a bit. The max size for an immediate shift is 8, so if you do it with 10, it will cost either two shifts or one register. The number of steps also add up to the final cycle count, so that LSL 3 costs half as much as LSL 6.

Originally Posted by E-Penguin

Although, frankly, you're probably better off creating a NewType with two members.

Indeed.

[idrougge]

Originally Posted by peceha

Hi
is there a way to make a variable global?
I would like to avoid "SHARED" statements inside all the procedures.

No.

[Daedalus]

AmiBlitz 3 allows you to declare global variables by using the SHARED keyword outside the procedures:

SHARED test.b
test = 10

Statement printtest{}
  NPrint test
End Statement

printtest{}
End

But of course comes with its own restrictions (FPU dependency, IDE requirements etc.).

[peceha]

This time I have a question about SuperTed

I opened the PREFS - changed the colors number to 16 (I think I also unchecked TOKENISE - btw. I do not know what it is for) and saved the configuration.

Now whenever I open SuperTed and load something I cannot see any text - I know it is there (scrollbar's size changes and I can even compile it ) - I just cannot see it.

How to fix it?


EDIT
ehh... forget it - the colors got changed when I played with screen modes.

[Daedalus]

Yep, it sounds like the foreground and background colours ended up being the same.

Tokenizing is when Blitz recognises a keyword and changes its colour to show you that it has understood. If you turn it off, SuperTED is essentially just a text editor. This option is to allow you to edit normal text files without having it capitalise certain words.

[peceha]

Thanks again Daedalus
If there is still someone willing to answer I have another one:

I'd like to load some shapes from IFF picture (16x16 tiles).
Can I have all of them in one picture or I need to have one tile per picture?

[TurboCrash]

One picture is enough, remember that the first color in the palette is the alpha/transparent color. So if using more than one palette it should be easier to divide graphics at least by palette.
LoadBitmap 1,"images.iff"
GetaShape 1,0,0,16,16
GetaShape 2,0,16,16,16

That's
GetaShape Shapenumber, start at X, start at Y, get Xpixels, get Ypixels

[peceha]

Thanks !!!

[idrougge]

If you draw them in one picture and surround each shape with a box, you can auto-grab them using RedShapeZ. It's part of the Blitz Support Suite and is installed automatically with the Ultimate Blitz CD. Just make sure you save them in the "Acid shapes" format.

[peceha]

Hi,
please take a look at the picture.
[/url]

On the left you can see my tileset (yes, I know ) and on the right you can see how it looks when the program runs.

Why do I have that gray color at all????
Gray color is not used in my tileset - I mean it is part of the palette but it is not used in drawing.
Funny thing is some tiles are half gray - half black or even white
I run it on WB in default 4 colors.
My tileset is an IFF image with 4 colors palette (same as WB and in the same order).

What am I doing wrong?

[idrougge]

I don't see any gray colour.

[peceha]

You need to zoom in a little. Then just look on the walls (should be black) but they are gray in some places. Same happens to "dots" -mostly are white but on some tiles they are grey. Also small "squares" in the middle of the tiles: should be white and black (as on the left picture) but they have some gray color in it.

[peceha]

Just one more
This one has nothing to do with my previous question.

I found an example of doing a commodity.
When I type it into AmiBlitz - all works fine.
When I type it into Blitz2, the following line gives me an error:

AddWaitEvent PortSigBit(CommodityMsgPort),$800000

saying that "array not yet Dim'd"
I know it is talking about PORTSIGBIT - how to fix it?

Thanks

[idrougge]

Funny, that compiles for me in Blitz 2.