Blitz Basic Questions

[E-Penguin]

Originally Posted by E-Penguin

PaletteRange Palette#,StartCol,EndCol,r0,g0,b0,r1,g1,b1 

PaletteRange creates a spread of colors within a palette. Similar to DPaint's spread
function PaletteRange takes a start and end colour and creates the color tweens
between them.

Does this work for anyone? I just get black in all the colour registers. I've gone as far as writing my own RGB interpolation function (which, sadly, I just lost because I didn't press save) but surely there must be a way of getting this to work.

As promised, here's my fixed version, for interpolating through the RGB colourspace. I'm still working on an HSV version. Example interpolation attached.

; By Daniel Lakey, 2018
; Distributed under attribution (CC-BY) licence. 
; Use as you will, a credit would be nice :)
; 
Function.w round{v.q}
	If Frac(v) >= 0.5
		Function Return (Int(v) + 1)
	Else
		Function Return int(v)
	EndIf
End Function

NewType .ntRGB
	r.b
	g.b
	b.b
End NewType

Statement PaletteRangeFixed_RGB{palette_num.w, color_start_num.b, color_end_num.b, *start_rgb.ntRGB, *end_rgb.ntRGB}
	steps.b = (color_end_num - color_start_num)
	t.f = 1/steps
	
	For i=0 to steps
		r_step.b = round{*start_rgb\r + (*end_rgb\r - *start_rgb\r)*(t*i)}
		g_step.b = round{*start_rgb\g + (*end_rgb\g - *start_rgb\g)*(t*i)}
		b_step.b = round{*start_rgb\b + (*end_rgb\b - *start_rgb\b)*(t*i)}
		
		PalRGB palette_num, color_start_num + i, r_step, g_step, b_step
	Next i
End Statement

; .....


  ; Use Palette Range to set the rest of the colours
  a.ntRGB\r=$F,0,0
  b.ntRGB\r=0,$F,0
  PaletteRangeFixed_RGB{#P_1, 2, 6, a, b}
  
  a.ntRGB\r=0,$F,0
  b.ntRGB\r=0,0,$F
  PaletteRangeFixed_RGB{#P_1, 6, 10, a, b}
  
  a.ntRGB\r=0,0,$F
  b.ntRGB\r=$F,0,0
  PaletteRangeFixed_RGB{#P_1, 10, 15, a, b}

[Master484]

I tested the PaletteRange command and it seems to work on classic Blitz 2.1 at least, but the color values given have to be between 0-255, even if it's an OCS screen with OCS palette.

Also you have to give the "Use Palette" or "DisplayPalette" command after PaletteRange, or else the changes won't take effect. So it works in the same way as PalRGB and other palette commands; the changes can't be seen until an Use Palette/DisplayPalette is executed.

[Cobe]

Is there a way to check disk activity?

[Daedalus]

Not really, no. It might be possible to do it for floppies by checking the motor bit on the CIAs, but no equivalent exists for hard drives, and anyway, there's no guarantee that some other task doesn't start disk access between you checking and doing something else...

[Cobe]

Thanks.. I feared its like that...

[E-Penguin]

Probably everyone already knows about this and I'm late to the party as usual, but the source code for blitz2, and various examples and BUMs not on the ubb dvd can be found here:
https://github.com/nitrologic/blitz2

Very interesting!

[idrougge]

Not found on the UBB CD? Anything in particular?

[E-Penguin]

Just lots of examples. I've not done an exhaustive comparison

[Cobe]

How can I generate error returncode?

[Daedalus]

Originally Posted by Cobe

How can I generate error returncode?

As in, return a value to AmigaDOS? I don't think it's possible (or at least, easy to do) with Blitz 2, but in AmiBlitz 3 you load the value you want to return into register d0, then use End d0 instead of End to quit the program.

[idrougge]

I think someone managed to hack that on the old Blitz mailing list. But you will have to search through many megabytes of Amigaguide files.

[Cobe]

Ah.. ok. Thanks guys.
And as I recall amiblitz needs fpu. Do all the executables compailed with it also require fpu?

[Daedalus]

Sometimes, even when using the integer optimisation mode. Certain commands will require an FPU (e.g. Val() ), but there isn't a comprehensive list that I know of, so there's always a risk. If the program is simple enough, you can probably try it on an FPU-less machine or WinUAE setup to confirm it works. It will most likely require a 68020 anyway, even if it works without an FPU. I've written a few programs like that and used work-arounds for commands I found that crashed the test system, e.g. using Vallong() instead of Val().

[Cobe]

Did it happen to anyone that debugger stops working seemingly all of a sudden? It just pops back to editor without any notice.

[attle]

Is this kind of simple nesting really not possible?

While some_condition
  If foo then
    Print "Error"
  EndIf
Wend

This generates the error message "Illegaly nested Condition"

Edit: EndIf, still the same thing

[idrougge]

While some_condition
  If foo
    Print "Error"
  EndIf
Wend

[attle]

Aha, so Then was the issue

[saimon69]

Originally Posted by Cobe

Did it happen to anyone that debugger stops working seemingly all of a sudden? It just pops back to editor without any notice.

You are lucky, in my WinUAE Blitz 2 debugger sent me in an instant trip to india every time i tried to use it :/

[Cobe]

Originally Posted by saimon69

You are lucky, in my WinUAE Blitz 2 debugger sent me in an instant trip to india every time i tried to use it :/

I was lucky too that few months before it happened I copied my Blitz folder to other lap top where debugger still worked. So I copied it back and everything's fine...
mmm except the fact that some libraries break the .xtra data so if I use them on every load I have to manually correct numbers...

[AlgoRythmic]

Hi, I have a question:
Can Mildred do 2x1 or 2x2 pixel ratio c2p internally? I mean other than 1x1 ofc.

Great thread btw