mirror of
https://github.com/cc65/cc65.git
synced 2024-09-27 04:54:54 +00:00
Remove dangling spaces and converts tabs to spaces
This commit is contained in:
Dave Plummer
parent
80ee84f136
commit
f1e3ba848f
@ -69,11 +69,11 @@ adp2:
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adp2_lo: .res 1
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adp2_hi: .res 1
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scroll_src:
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scroll_src:
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scroll_src_lo: .res 1
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scroll_src_hi: .res 1
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scroll_src_hi: .res 1
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scroll_dest:
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scroll_dest:
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scroll_dest_lo: .res 1
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scroll_dest_hi: .res 1
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@ -103,9 +103,9 @@ pixel: .res 1
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xval: .res 2 ; These could move to zeropage for perf, but presume we
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yval: .res 2 ; we want to minimize the amount we grow zero page use
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err: .res 2
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err: .res 2
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temp: .res 2
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tempa: .res 1
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tempa: .res 1
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tempx: .res 1
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tempy: .res 1
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temp2: .res 2
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@ -131,11 +131,11 @@ tempstr: .res 2
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; Based on MTU PIXADR code
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;-----------------------------------------------------------------------------------
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; In: _x1cord (16-bit)
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; _y1cord (16-bit)
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; Out: adp1 (16-bit) Address of pixel to set
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; _y1cord (16-bit)
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; Out: adp1 (16-bit) Address of pixel to set
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;-----------------------------------------------------------------------------------
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_GetPixelAddress:
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_GetPixelAddress:
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lda _x1cord ; compute bit address first
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sta adp1 ; also transfer x1cord to adp1
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and #$07 ; + which is simply the low 3 bits of x
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@ -181,7 +181,7 @@ _GetPixelAddress:
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adc adp1+1
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adc #>SCREEN ; add in vmorg*256
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sta adp1+1 ; final result
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rts ; return
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rts ; return
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;-----------------------------------------------------------------------------------
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; Mask tables for individual pixel subroutines
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@ -220,7 +220,7 @@ _Delay: pha
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; SetPixel - Set a pixel in the video memory
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;-----------------------------------------------------------------------------------
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; x - _x1cord (16-bit)
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; y - _y1cord (16-bit)
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; y - _y1cord (16-bit)
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;-----------------------------------------------------------------------------------
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; Mask tables for individual pixel subroutines
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;-----------------------------------------------------------------------------------
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@ -228,25 +228,25 @@ _Delay: pha
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_SetPixel: jsr _GetPixelAddress
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ldy btpt ; get bit number in y
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lda msktb1,y ; get a byte with that bit =1, others =0
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ldy #0
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ldy #0
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ora (adp1),y ; combine the bit with the addressed vm
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sta (adp1),y ; byte
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rts
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rts
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;-----------------------------------------------------------------------------------
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; ClearPixel - Clears a pixel in the video memory
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;-----------------------------------------------------------------------------------
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; x - _x1cord (16-bit)
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; y - _y1cord (16-bit)
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; y - _y1cord (16-bit)
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;-----------------------------------------------------------------------------------
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_ClearPixel: jsr _GetPixelAddress
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ldy btpt ; get bit number in y
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lda msktb2,y ; get a byte with that bit =0, others =1
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ldy #0
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ldy #0
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and (adp1),y ; remove the bit from the addressed vm
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sta (adp1),y ; byte
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rts
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rts
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;-----------------------------------------------------------------------------------
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; ClearScreen - Clears the entire video memory (and thus the screen)
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@ -262,21 +262,21 @@ _ClearScreen:
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ldy #0
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: sta (dest), y ; Loop unwound by a factor of 8, which means our iny before the branchh
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iny ; will still work as it's on a page crossing boundary.
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iny ; will still work as it's on a page crossing boundary.
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sta (dest), y ; This will avoid most of the overhead of the branch.
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iny
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iny
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sta (dest), y
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iny
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iny
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sta (dest), y
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iny
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iny
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sta (dest), y
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iny
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iny
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sta (dest), y
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iny
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iny
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sta (dest), y
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iny
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iny
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sta (dest), y
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iny
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iny
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bne :-
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inc dest_hi
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@ -319,8 +319,8 @@ _ScrollScreen:
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lda (scroll_src),y ; I've unwound the loop to do 8 bytes at a time. Since we're doing full pages
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sta (scroll_dest),y ; as long as we unwind the loop to do 8 bytes at a time, we know we'll still
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iny ; do the final increment on a page boundary.
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lda (scroll_src),y
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iny ; do the final increment on a page boundary.
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lda (scroll_src),y
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sta (scroll_dest),y
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iny
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lda (scroll_src),y
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@ -358,7 +358,7 @@ fullPageLoop:
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sta (scroll_dest_lo),y
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iny
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bne fullPageLoop
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inc scroll_dest_hi
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inc scroll_dest_hi
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partialPageLoop:
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sta (scroll_dest_lo),y
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iny
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@ -376,7 +376,7 @@ partialPageLoop:
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; DrawCircle - Draws a circle in video memory of a given radius at a given coord
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;-----------------------------------------------------------------------------------
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; x - _x1cord (16-bit)
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; y - _y1cord (16-bit)
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; y - _y1cord (16-bit)
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; radius - _y2cord (16-bit)
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;-----------------------------------------------------------------------------------
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; Implements the midpoint circle algorithm without floating point or trig functions
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@ -384,8 +384,8 @@ partialPageLoop:
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; int x = radius;
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; int y = 0;
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; int err = 0;
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;
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; while (x >= y)
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;
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; while (x >= y)
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; {
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; SETPIXEL(x0 + x, y0 + y, val);
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; SETPIXEL(x0 + y, y0 + x, val);
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@ -395,7 +395,7 @@ partialPageLoop:
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; SETPIXEL(x0 - y, y0 - x, val);
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; SETPIXEL(x0 + y, y0 - x, val);
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; SETPIXEL(x0 + x, y0 - y, val);
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;
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;
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; y++;
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; err += 1 + 2 * y;
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; if (2 * (err - x) + 1 > 0) {
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@ -418,20 +418,20 @@ _DrawCircle: lda _x1cord ; x0 = _x1cord
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sta xval
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lda _y2cord+1
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sta xval+1
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lda #$0 ; yval = 0;
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sta yval
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sta yval+1
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sta err ; err = 0;
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sta err+1
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circleloop:
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sta err+1
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circleloop:
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lda xval+1 ; if (xval < yval) we're done;
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sec
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cmp yval+1
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bcc doneCircle ; if high byteof yval is greater, we can draw
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bne doCircle ; it not greater and not equal, is less, so done
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lda xval ; in other cases we need to compare the LSB next
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cmp yval
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cmp yval
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bcs doCircle ; if it's less, but MSB was equal, we go draw
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doneCircle: rts
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@ -451,7 +451,7 @@ doCircle: lda x0 ; Draw the first of 8 symmetric
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sbc xval+1
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sta _y1cord+1
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jsr _SetPixel ; SETPIXEL(x0 + y, y0 - x, val);
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lda x0
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sec
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sbc yval
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@ -467,7 +467,7 @@ doCircle: lda x0 ; Draw the first of 8 symmetric
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sbc xval+1
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sta _y1cord+1
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jsr _SetPixel ; SETPIXEL(x0 - y, y0 - x, val);
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lda x0
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sec
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sbc xval
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@ -483,7 +483,7 @@ doCircle: lda x0 ; Draw the first of 8 symmetric
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sbc yval+1
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sta _y1cord+1
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jsr _SetPixel ; SETPIXEL(x0 - x, y0 - y, val);
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lda x0
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sec
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sbc xval
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@ -499,7 +499,7 @@ doCircle: lda x0 ; Draw the first of 8 symmetric
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adc yval+1
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sta _y1cord+1
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jsr _SetPixel ; SETPIXEL(x0 - x, y0 + y, val);
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lda x0
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clc
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adc yval
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@ -515,7 +515,7 @@ doCircle: lda x0 ; Draw the first of 8 symmetric
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adc xval+1
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sta _y1cord+1
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jsr _SetPixel ; SETPIXEL(x0 + y, y0 + x, val);
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lda x0
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clc
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adc xval
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@ -531,7 +531,7 @@ doCircle: lda x0 ; Draw the first of 8 symmetric
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adc yval+1
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sta _y1cord+1
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jsr _SetPixel ; SETPIXEL(x0 + x, y0 + y, val);
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lda x0
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clc
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adc xval
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@ -547,7 +547,7 @@ doCircle: lda x0 ; Draw the first of 8 symmetric
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sbc yval+1
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sta _y1cord+1
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jsr _SetPixel ; SETPIXEL(x0 + x, y0 - y, val);
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lda x0
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sec
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sbc yval
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@ -572,12 +572,12 @@ doCircle: lda x0 ; Draw the first of 8 symmetric
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asl
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sta temp
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lda yval+1
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rol
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rol
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sta temp+1
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inc temp
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bne :+
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inc temp+1
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:
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:
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lda err ; err += temp
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clc
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adc temp
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@ -586,20 +586,20 @@ doCircle: lda x0 ; Draw the first of 8 symmetric
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adc temp+1
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sta err+1
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; if (2 * (err - xval) + 1 > 0) then dec xval
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lda err ; temp = err-xval
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lda err ; temp = err-xval
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sec
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sbc xval
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sta temp
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lda err+1
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sbc xval+1
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sta temp+1
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asl temp ; temp = 2*(err-xval)+1
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rol temp+1
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inc temp
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inc temp
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bne :+
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inc temp+1
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:
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:
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lda temp+1 ; if (temp > 0) we'll dec xval
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bmi doneLoop ; less than zero, so no dec
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bne decxval ; if not zero, go ahead and dec
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@ -626,7 +626,7 @@ updateerr: lda xval ; temp = xval * 2
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lda #0
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sbc temp+1
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sta temp2+1
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lda err ; err += 1-(xval*2)
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clc
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adc temp2
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@ -634,7 +634,7 @@ updateerr: lda xval ; temp = xval * 2
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lda err+1
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adc temp2+1
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sta err+1
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doneLoop: jmp circleloop
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;-----------------------------------------------------------------------------------
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@ -659,8 +659,8 @@ ascToPetTable: .byte $00,$01,$02,$03,$04,$05,$06,$07,$14,$20,$0d,$11,$93,$0a,$0
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.byte $f0,$f1,$f2,$f3,$f4,$f5,$f6,$f7,$f8,$f9,$fa,$fb,$fc,$fd,$fe,$ff
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; PETSCI to Ascii lookup table - not current used, so commented out, but can be used to map fonts
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;
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;
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;
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;
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petToAscTable: .byte $00,$01,$02,$03,$04,$05,$06,$07,$14,$09,$0d,$11,$93,$0a,$0e,$0f
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.byte $10,$0b,$12,$13,$08,$15,$16,$17,$18,$19,$1a,$1b,$1c,$1d,$1e,$1f
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.byte $20,$21,$22,$23,$24,$25,$26,$27,$28,$29,$2a,$2b,$2c,$2d,$2e,$2f
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@ -686,9 +686,9 @@ ascToPetTable: .byte $00,$01,$02,$03,$04,$05,$06,$07,$14,$20,$0d,$11,$93,$0a,$0
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_AscToPet: tay
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lda ascToPetTable, y
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rts
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rts
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_PetToAsc: tay
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_PetToAsc: tay
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lda petToAscTable, Y
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rts
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@ -762,7 +762,7 @@ ScreenLineAddresses:
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_DrawChar: sty tempy
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stx tempx
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sta tempa
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tya ; Get the address in screen memory where this
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asl ; character X/Y cursor pos should be drawn
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tay
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@ -773,20 +773,20 @@ _DrawChar: sty tempy
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lda ScreenLineAddresses+1, y
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adc #0
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sta dest_hi
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lda #0 ; Get the address in font memory where this
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sta src_hi ; Petscii chracter lives (after conversion from
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lda tempa ; ascii)
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sty temp2
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jsr _AscToPet
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ldy temp2
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asl
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asl
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rol src_hi
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asl
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asl
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rol src_hi
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asl
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asl
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rol src_hi
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clc
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adc #<_font8x8_basic ; Add the base address of the font table to the offset
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@ -794,23 +794,23 @@ _DrawChar: sty tempy
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lda src_hi
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adc #>_font8x8_basic
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sta src_hi
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ldy #0 ; opy the character def to the screen, one byte at a time
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ldx #0
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: lda (src), y ; Copy this byte from the character def to the screen target
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sta (dest, x)
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lda dest_lo ; Advance to the next "scanline", or pixel row, down
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clc
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adc #<BYTESPERROW
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adc #<BYTESPERROW
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sta dest_lo
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lda dest_hi
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adc #>BYTESPERROW
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sta dest_hi
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iny
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cpy #8
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bne :-
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ldy tempy
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ldx tempx
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lda tempa
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@ -831,7 +831,7 @@ CursorOff: ldx _cursorX
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lda #' '
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jsr _DrawChar
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rts
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;-----------------------------------------------------------------------------------
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; DrawText - Draws an ASCII char in A at the current cursor pos, saves all regs
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;-----------------------------------------------------------------------------------
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@ -841,13 +841,13 @@ _CharOut: sta temp
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sta temp+1
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txa
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pha
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tya
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tya
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pha
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ldx #<temp
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ldy #>temp
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jsr _DrawText
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jsr _DrawText
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pla
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tay
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pla
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@ -865,7 +865,7 @@ Backspace: lda _cursorX
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dec _cursorX
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jsr CursorOn
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colzero: rts
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;-----------------------------------------------------------------------------------
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; DrawText - Draws an ASCII string at the current cursor position
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;-----------------------------------------------------------------------------------
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@ -875,34 +875,34 @@ colzero: rts
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_DrawText: stx adp1_lo
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sty adp1_hi
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jsr CursorOff
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ldy #0
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checkHWrap: lda _cursorX
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cmp #CHARSPERROW
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bcc checkVWrap
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lda #0
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sta _cursorX
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inc _cursorY
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inc _cursorY
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checkVWrap: lda _cursorY
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cmp #ROWSPERCOLUMN
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bcc loadChar
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jsr _ScrollScreen
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lda #ROWSPERCOLUMN-1
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sta _cursorY
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loadChar: lda (adp1), y
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beq doneText
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cmp #$0a
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bne :+
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lda #0 ; Back to the left edge
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sta _cursorX
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inc _cursorY ; Advance to the next line
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iny
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bne checkHWrap
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: sty temp
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ldx _cursorX
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ldy _cursorY
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@ -911,14 +911,14 @@ loadChar: lda (adp1), y
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inc _cursorX
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iny
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bne checkHWrap
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doneText: jsr CursorOn
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rts
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rts
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demoText1: .byte " *** COMMODORE KIM-1 SHELL V0.1 ***", $0A, $0A
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.byte " 60K RAM SYSTEM. 49152 BYTES FREE.", $0A, $0A, $00
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readyText: .byte $0A,"READY.", $0A, 00
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_Demo: jsr _ClearScreen
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lda #0
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sta _cursorX
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@ -927,7 +927,7 @@ _Demo: jsr _ClearScreen
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ldy #>demoText1
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jsr _DrawText
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rts
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_Ready: ldx #<readyText
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ldy #>readyText
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jsr _DrawText
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@ -938,7 +938,7 @@ _Ready: ldx #<readyText
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; DrawLine - Draws a line between two points
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;-----------------------------------------------------------------------------------
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; _x1cord (16-bit)
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; _y1cord ( 8-bit)
|
||||
; _y1cord ( 8-bit)
|
||||
; _x2cord (16-bit)
|
||||
; _y2cord ( 8-bit)
|
||||
;-----------------------------------------------------------------------------------
|
||||
@ -949,16 +949,16 @@ _Ready: ldx #<readyText
|
||||
; int dx = abs(_x2cord - _x1cord), sx = _x1cord < _x2cord ? 1 : -1;
|
||||
; int dy = abs(_y2cord - _y1cord), sy = _y1cord < _y2cord ? 1 : -1;
|
||||
; int err = (dx > dy ? dx : -dy) / 2, e2;
|
||||
;
|
||||
;
|
||||
; while (1)
|
||||
; {
|
||||
; SETPIXEL(_x1cord, _y1cord, val);
|
||||
;
|
||||
;
|
||||
; if (_x1cord == _x2cord && _y1cord == _y2cord)
|
||||
; break;
|
||||
;
|
||||
;
|
||||
; e2 = err;
|
||||
;
|
||||
;
|
||||
; if (e2 > -dx)
|
||||
; {
|
||||
; err -= dy;
|
||||
@ -974,12 +974,12 @@ _Ready: ldx #<readyText
|
||||
;-----------------------------------------------------------------------------------
|
||||
|
||||
_DrawLine: sta pixel
|
||||
|
||||
|
||||
ldx #$01 ; positive x-step for now
|
||||
stx sx
|
||||
|
||||
|
||||
; Calculate dx = (x2cord - X1cord) and see if its positive or not
|
||||
|
||||
|
||||
lda _x2cord ; Calculate dx = (x2cord - X1cord)
|
||||
sec
|
||||
sbc _x1cord
|
||||
@ -988,10 +988,10 @@ _DrawLine: sta pixel
|
||||
sbc _x1cord+1
|
||||
sta dx+1
|
||||
bpl calcdy ; dx is positive (dx >= 0), so we're good
|
||||
|
||||
|
||||
; dx was negative (dx < 0), so we set sx to -1 and get the absolute
|
||||
; value by subtracting the other direction
|
||||
|
||||
|
||||
ldx #$FF ; negative x-step
|
||||
stx sx
|
||||
lda _x1cord ; Calculate dx = (x2cord - X1cord)
|
||||
@ -1001,9 +1001,9 @@ _DrawLine: sta pixel
|
||||
lda _x1cord+1
|
||||
sbc _x2cord+1
|
||||
sta dx+1
|
||||
|
||||
|
||||
; Calculate dy = (y2cord - y1cord) and see if its positive or not
|
||||
|
||||
|
||||
calcdy: ldx #$01 ; positive y-step for now
|
||||
stx sy
|
||||
lda _y2cord
|
||||
@ -1011,25 +1011,25 @@ calcdy: ldx #$01 ; positive y-step for now
|
||||
sbc _y1cord
|
||||
sta dy
|
||||
bcs positivedy ; If y2cord > y1cord, then dy is positive and we're good
|
||||
|
||||
|
||||
; dy was negative (dy < 0), so we set sy to -1 and get the absolute value
|
||||
|
||||
|
||||
ldx #$FF ; negative y-step
|
||||
stx sy
|
||||
lda _y1cord
|
||||
sec
|
||||
sbc _y2cord
|
||||
sta dy
|
||||
|
||||
|
||||
; Now we have dx and dy, so we can calculate err, but first we need
|
||||
; to see if dx > dy or not
|
||||
|
||||
|
||||
positivedy: lda dx+1 ; Check if dx > dy (both are always positive now)
|
||||
bne dxgt ; If MSB of dx is greater than zero, then dx > dy since dy is 8-bits
|
||||
lda dy
|
||||
cmp dx
|
||||
bcs dygte
|
||||
|
||||
|
||||
dxgt: lda dx ; We found dx>dy so set err = dx / 2
|
||||
sta err
|
||||
lda dx+1
|
||||
@ -1037,7 +1037,7 @@ dxgt: lda dx ; We found dx>dy so set err = dx / 2
|
||||
sta err+1 ; err = dx/2
|
||||
ror err
|
||||
jmp loop
|
||||
|
||||
|
||||
dygte: lda #0 ; we found dx <= dy so set err = -dy / 2
|
||||
sec
|
||||
sbc dy ; else err = -dy / 2
|
||||
@ -1046,15 +1046,15 @@ dygte: lda #0 ; we found dx <= dy so set err = -dy / 2
|
||||
sta err
|
||||
lda #$FF
|
||||
sta err+1
|
||||
|
||||
|
||||
; Now we have dx, dy, and err, so we can start drawing pixels
|
||||
|
||||
|
||||
loop: lda pixel
|
||||
beq clearpixel
|
||||
jsr _SetPixel ; Plot the current _x1cord, _y1cord
|
||||
jmp next
|
||||
clearpixel: jsr _ClearPixel ; Clear the current _x1cord, _y1cord
|
||||
|
||||
|
||||
next: lda _x1cord ; if (_x1cord == _x2cord && _y1cord == _y2cord) then we rts
|
||||
cmp _x2cord
|
||||
bne noteq
|
||||
@ -1064,16 +1064,16 @@ next: lda _x1cord ; if (_x1cord == _x2cord && _y1cord == _
|
||||
lda _x1cord+1
|
||||
cmp _x2cord+1
|
||||
bne noteq
|
||||
|
||||
|
||||
rts
|
||||
|
||||
|
||||
noteq: lda err ; e2 = err
|
||||
sta e2
|
||||
lda err+1
|
||||
sta e2+1
|
||||
|
||||
|
||||
; Check the two update conditions for x and y, and update if needed
|
||||
|
||||
|
||||
lda e2 ; if (e2 > -dx) is the same as if (e2 + dx > 0), so we test that because its easier
|
||||
clc ; If its true then we dec err and inc _x1cord
|
||||
adc dx
|
||||
@ -1091,7 +1091,7 @@ incxval: inc _x1cord ; _x1cord += 1 because sx == 1
|
||||
bne updatexerr
|
||||
inc _x1cord+1
|
||||
jmp updatexerr
|
||||
|
||||
|
||||
decx: lda _x1cord ; _x1cord += 1 because sx == 1
|
||||
sec
|
||||
sbc #1
|
||||
@ -1099,37 +1099,37 @@ decx: lda _x1cord ; _x1cord += 1 because sx == 1
|
||||
lda _x1cord+1
|
||||
sbc #0
|
||||
sta _x1cord+1
|
||||
|
||||
updatexerr: lda err ; err -= dy
|
||||
|
||||
updatexerr: lda err ; err -= dy
|
||||
sec
|
||||
sbc dy
|
||||
sta err
|
||||
lda err+1
|
||||
sbc #0
|
||||
sta err+1
|
||||
|
||||
doneupdatex: lda e2+1 ; if (e2 < dy) then we inc err and inc _y1cord
|
||||
|
||||
doneupdatex: lda e2+1 ; if (e2 < dy) then we inc err and inc _y1cord
|
||||
bmi updateerry ; If MSB is negative, then e2 < dy, so we inc err and inc _y1cord
|
||||
bne noupdatey ; If the MSB of e2 is set and positive, then we know e2 > dy, so we don't inc err or inc _y1cord
|
||||
lda e2
|
||||
lda e2
|
||||
sec
|
||||
sbc dy
|
||||
sbc dy
|
||||
beq noupdatey ; e2 - dy == 0 so we don't inc err or inc _y1cord
|
||||
bcs noupdatey ; if e2 was large enough that carry never cleared, then e2 > dy do no update
|
||||
|
||||
updateerry: lda err ; err += dx
|
||||
|
||||
updateerry: lda err ; err += dx
|
||||
clc
|
||||
adc dx
|
||||
sta err
|
||||
lda err+1
|
||||
adc dx+1
|
||||
sta err+1
|
||||
|
||||
|
||||
stepy: lda _y1cord
|
||||
clc
|
||||
adc sy
|
||||
sta _y1cord
|
||||
|
||||
|
||||
noupdatey: jmp loop
|
||||
|
||||
_getch: jsr $1E5A ; Get character using Monitor ROM call
|
||||
|
||||
Loading…
Reference in New Issue
Block a user