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Hawk

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Posted: 12:25am 09 Mar 2023

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Following on from my last question regarding details for defining new fonts, is it possible to define multicolour fonts?

In 320x240 mode, is the font data interpreted as two bits of font data per pixel?

Thanks,
Mike

JohnS
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Posted: 07:45am 09 Mar 2023

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I don't think so. When you output text so long as you follow the tile/etc rules it'll acquire the current colours you've set.

John

matherp
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Posted: 07:59am 09 Mar 2023

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Quote In 320x240 mode, is the font data interpreted as two bits of font data per pixel?

Yes

Martin H.

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Posted: 10:31am 09 Mar 2023

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Hawk said Following on from my last question regarding details for defining new fonts, is it possible to define multicolour fonts?

In 320x240 mode, is the font data interpreted as two bits of font data per pixel?

Thanks,
Mike

the Font (like gui Bitmap) uses one Bit /Pixel so you will not get more than 2 Colors per Char (Foreground and background color) using TEXT or PRINT Command.
The Only way I see, is load a Picture of the Multicolor-Font to the Frame Buffer and write a little Sub that places a String on the Screen via Sprite Read/ Sprite Write.
Edited 2023-03-09 20:42 by Martin H.

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Hawk

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Posted: 11:15pm 09 Mar 2023

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matherp said

Quote In 320x240 mode, is the font data interpreted as two bits of font data per pixel?

Yes

Sorry, I should have clarified this question a bit further...in 320x240 mode, does the graphics engine interpret the two bits of data per pixel as colour information?

I grew up with an Atari 8-bit, and am accustomed to getting more colour as the horizontal resolution decreased. I was wondering whether this is the same for the PicMiteVGA?

From reading other responses, it is more like the ZX Spectrum, allowing any foreground/background colour from a palette of 16 fixed colours for a whole charater.

I'm OK having limitations, I am just trying to determine what limitations I am working to.

Hawk

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Posted: 11:18pm 09 Mar 2023

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Martin H. said

I like this idea. Is the Framebuffer the only place to load a bitmap? Can it just sit in arbitary memory?

Martin H.

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Posted: 07:37am 10 Mar 2023

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Multicolor Font...
Little Demo (Ugly but it is just for Demonstration)

'demo
MODE 2
Dim integer f,n,cl,col
FRAMEBUFFER create
FRAMEBUFFER write f
'first build an Multicolor Font Page in Framebuffer
CLS :Font 1
cl=1
For f=32 To 127:Print Chr$(f);:Next
For f=0 To 36
col=&HFF*(CL And 1)+&HFF00*((CL And 2)=2)+&HFF0000*((CL And 4)=4)
For n=0 To 319
If Pixel(n,f) Then Pixel n,f,col
Next n
Inc cl:cl=cl And 7
Next f
coltext 0,120,"Print a Text in Multicolor"
'---------------------------
Sub coltext x,y,c$
Local integer f,sx,sy
For f= 1 To Len(c$)
'calc source coordinates
sy=0
sx=8*(Asc(Mid$(c$,f,1))-32)
Do
If sx>=320 Then Inc sx,-320:Inc sy,12
Loop Until sx<320
FRAMEBUFFER write f
Sprite read #1,sx,sy,8,8
FRAMEBUFFER write n
Sprite write #1,x,y
'calc dest. coordinates
Inc x,8:If x>319 Then x=0:Inc y,12
Next
End Sub

of course you can also load a prepared image of your multicolor font into the framebuffer
Edited 2023-03-10 17:53 by Martin H.

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Mixtel90

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Posted: 08:27am 10 Mar 2023

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Hawk said I like this idea. Is the Framebuffer the only place to load a bitmap? Can it just sit in arbitary memory?

There is no such thing as arbitrary memory on the PicoMite. Every last byte is either used or reserved for something. :)

Just a thought... Would this be possible?
If the font character data is small enough, they could be poked into strings as we know where they are and how long. A string could then be copied to the framebuffer (not PRINTed) as required. Strings can be written as files so characters could be stored and loaded as required.
Edited 2023-03-10 18:28 by Mixtel90

Mick

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Martin H.

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Posted: 09:27am 10 Mar 2023

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Mixtel90 said A string could then be copied to the framebuffer (not PRINTed) as required. Strings can be written as files so characters could be stored and loaded as required.

That makes me curious... How do I copy a string to the memory area of the screen or framebuffer?

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Mixtel90

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Posted: 09:35am 10 Mar 2023

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I don't know yet. :)
You can PEEK it character by character, of course. The zeroeth character of the string is its length.
I'm *assuming* that the frame buffer is some sort of linear map that could be POKEable. It's just an idea. Could the string data be a sprite?

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

Martin H.

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Posted: 10:30am 10 Mar 2023

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Mixtel90 said I don't know yet. :)
You can PEEK it character by character, of course. The zeroeth character of the string is its length.
I'm *assuming* that the frame buffer is some sort of linear map that could be POKEable. It's just an idea. Could the string data be a sprite?

so far so good
with VARADDR var$ - I get the address of the String,
1st Byte is the lenght String.
But sadly, I have no address for Screen (n) or Framebuffer(f) or the memory area in which the sprites are stored to POKE or move anything to.

I was hoping I just missed it and you would have the answer
Edited 2023-03-10 20:33 by Martin H.

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Mixtel90

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Posted: 10:38am 10 Mar 2023

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Oh well, it was something to think about. :)

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

Martin H.

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Posted: 10:58am 10 Mar 2023

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I found an error in my listing.

'demo
MODE 2
Dim integer f,n,cl,col
FRAMEBUFFER create
FRAMEBUFFER write f
'first build an Multicolor Font Page in Framebuffer
CLS :Font 1
cl=1
For f=32 To 127:Print Chr$(f);:Next
For f=0 To 36
col=&HFF*(CL And 1)+&HFF00*((CL And 2)=2)+&HFF0000*((CL And 4)=4)
For n=0 To 319
If Pixel(n,f) Then Pixel n,f,col
Next n
Inc cl:cl=cl And 7
Next f
FRAMEBUFFER write n
CLS &H004000
coltext 0,120,"Print a Text in Multicolor"
'---------------------------
Sub coltext x,y,c$
Local integer f,sx,sy
For f= 1 To Len(c$)
'calc source coordinates
sy=0
sx=8*(Asc(Mid$(c$,f,1))-32)
Do
If sx>=320 Then Inc sx,-320:Inc sy,12
Loop Until sx<320
FRAMEBUFFER write f
Sprite read #1,sx,sy,8,12
FRAMEBUFFER write n
Sprite write #1,x,y
'calc next dest. coordinates
Inc x,8:If x>319 Then x=0:Inc y,12
Next
End Sub

Since the font is 8x12 Pixel, it has to be Sprite read #1,sx,sy,8,12 not Sprite read #1,sx,sy,8,8
Edited 2023-03-12 00:51 by Martin H.

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