commit cda02143cdd067d8847391ae53dfc1bf0c0c0e7a
parent 92397ff105b0be239ed5c6c6785da56dd7b319b5
Author: neauoire <aliceffekt@gmail.com>
Date: Fri, 12 Feb 2021 19:51:39 -0800
Improved draw example
Diffstat:
3 files changed, 61 insertions(+), 16 deletions(-)
diff --git a/build.sh b/build.sh
@@ -24,5 +24,5 @@ rm -f ./bin/emulator
cc -std=c89 -DDEBUG -Wall -Wno-unknown-pragmas -Wpedantic -Wshadow -Wextra -Werror=implicit-int -Werror=incompatible-pointer-types -Werror=int-conversion -Wvla -g -Og -fsanitize=address -fsanitize=undefined uxn.c emulator.c -L/usr/local/lib -lSDL2 -o bin/emulator
# run
-./bin/assembler examples/line.usm bin/boot.rom
+./bin/assembler examples/draw.usm bin/boot.rom
./bin/emulator bin/boot.rom
diff --git a/examples/draw.usm b/examples/draw.usm
@@ -4,6 +4,7 @@
:dev/w fff9 ( std write port )
;x_ 2 ;y_ 2 ;x 2 ;y 2 ;w 2 ;h 2 ;color 1
+;x0 2 ;y0 2 ;x1 2 ;y1 2 ;dx 2 ;dy 2 ;err1 2 ;err2 2 ( line )
|0100 @RESET
@@ -38,6 +39,23 @@
( fill rect x y w h )
,0028 ,0038 ,0050 ,0030 ,linerect JSR
+
+ ( positive )
+ ,01 ,color STR
+ +0030 ,x0 STR^ +0040 ,y0 STR^
+ +0100 ,x1 STR^ +0060 ,y1 STR^
+ ,line JSR
+
+ ,02 ,color STR
+ +0020 ,x0 STR^ +0010 ,y0 STR^
+ +0090 ,x1 STR^ +0070 ,y1 STR^
+ ,line JSR
+
+ ,03 ,color STR
+ +0010 ,x0 STR^ +0040 ,y0 STR^
+ +0070 ,x1 STR^ +0060 ,y1 STR^
+ ,line JSR
+
,redraw JSR
BRK
@@ -70,6 +88,31 @@ BRK
,x_ LDR^ ,w LDR^ ,x LDR^ ADD^ ,0001 ADD^ LTH^ ,linerectrow ROT JMP? POP^
RTS
+@line
+ ,x0 LDR^ ,x_ STR^ ,y0 LDR^ ,y_ STR^ ( start at x0,y0 )
+ ,x1 LDR^ ,x0 LDR^ ,diff16sub JSR ,dx STR^ ( int dx = abs[x1 - x0] )
+ ,y1 LDR^ ,y0 LDR^ ,diff16sub JSR -0001 MUL!^ ,dy STR^ ( int dy = -abs[y1 - y0] )
+ ,dx LDR^ ,dy LDR^ ADD!^ ,err1 STR^ ( int err1 = dx + dy, e2; )
+ @lineloop
+ ,x_ LDR^ ,y_ LDR^ ,putpixel JSR ( draw )
+ @line-x
+ ,err1 LDR^ +0002 MUL!^ ,err2 STR^ ( e2 = 2 * err; )
+ ,err2 LDR^ ,dy LDR^ LTH!^ ,line-y ROT JMP? POP^ ( e2 >= dy )
+ ,err1 LDR^ ,dy LDR^ ADD!^ ,err1 STR^ ( err1 += dy; )
+ ,x_ LDR^ +0001 ADD!^ ,x_ STR^ ( y0 += y0 < y1 ? 1 : -1; )
+ @line-y
+ ,err2 LDR^ ,dx LDR^ GTH!^ ,line-end ROT JMP? POP^ ( e2 <= dx )
+ ,err1 LDR^ ,dx LDR^ ADD!^ ,err1 STR^ ( err1 += dx; )
+ ,y_ LDR^ +0001 ADD!^ ,y_ STR^ ( y0 += y0 < y1 ? 1 : -1; )
+ @line-end
+ ,x_ LDR^ ,x1 LDR^ NEQ!^ ,lineloop ROT JMP? POP^ ( loop )
+ RTS
+
+@diff16
+ OVR^ OVR^ GTH^ ,diff16sub ROT JMP? POP^
+ SWP^ @diff16sub SUB^
+RTS
+
@redraw
,0000 IOW^
,0000 IOW^
diff --git a/examples/line.usm b/examples/line.usm
@@ -3,27 +3,28 @@
:dev/r fff8 ( std read port )
:dev/w fff9 ( std write port )
-;x_ 2 ;y_ 2 ;x0 2 ;y0 2 ;x1 2 ;y1 2 ;color 1
-;dx 2 ;dy 2 ;err 2 ;err2 2
+;x_ 2 ;y_ 2 ;color 1
+;x0 2 ;y0 2 ;x1 2 ;y1 2 ;dx 2 ;dy 2 ;err1 2 ;err2 2
|0100 @RESET
( set dev/write to screen )
,01 ,dev/w STR
+ ( positive )
,01 ,color STR
+0030 ,x0 STR^ +0040 ,y0 STR^
- +0050 ,x1 STR^ +0060 ,y1 STR^
+ +0100 ,x1 STR^ +0060 ,y1 STR^
,line JSR
,02 ,color STR
+0020 ,x0 STR^ +0010 ,y0 STR^
- +0060 ,x1 STR^ +0070 ,y1 STR^
+ +0090 ,x1 STR^ +0070 ,y1 STR^
,line JSR
,03 ,color STR
+0010 ,x0 STR^ +0040 ,y0 STR^
- +0080 ,x1 STR^ +0060 ,y1 STR^
+ +0070 ,x1 STR^ +0060 ,y1 STR^
,line JSR
( draw control points )
@@ -39,19 +40,20 @@ BRK
,x0 LDR^ ,x_ STR^ ,y0 LDR^ ,y_ STR^ ( start at x0,y0 )
,x1 LDR^ ,x0 LDR^ ,diff16sub JSR ,dx STR^ ( int dx = abs[x1 - x0] )
,y1 LDR^ ,y0 LDR^ ,diff16sub JSR -0001 MUL!^ ,dy STR^ ( int dy = -abs[y1 - y0] )
- ,dx LDR^ ,dy LDR^ ADD!^ ,err STR^ ( int err = dx + dy, e2; )
- @loop
+ ,dx LDR^ ,dy LDR^ ADD!^ ,err1 STR^ ( int err1 = dx + dy, e2; )
+ @lineloop
,x_ LDR^ ,y_ LDR^ ,putpixel JSR ( draw )
- ,err LDR^ +0002 MUL!^ ,err2 STR^ ( e2 = 2 * err; )
- ,err2 LDR^ ,dy LDR^ LTH!^ ,continue1 ROT JMP? POP^ ( e2 >= dy )
- ,err LDR^ ,dy LDR^ ADD!^ ,err STR^ ( err += dy; )
+ @line-x
+ ,err1 LDR^ +0002 MUL!^ ,err2 STR^ ( e2 = 2 * err; )
+ ,err2 LDR^ ,dy LDR^ LTH!^ ,line-y ROT JMP? POP^ ( e2 >= dy )
+ ,err1 LDR^ ,dy LDR^ ADD!^ ,err1 STR^ ( err1 += dy; )
,x_ LDR^ +0001 ADD!^ ,x_ STR^ ( y0 += y0 < y1 ? 1 : -1; )
- @continue1
- ,err2 LDR^ ,dx LDR^ GTH!^ ,continue2 ROT JMP? POP^ ( e2 <= dx )
- ,err LDR^ ,dx LDR^ ADD!^ ,err STR^ ( err += dx; )
+ @line-y
+ ,err2 LDR^ ,dx LDR^ GTH!^ ,line-end ROT JMP? POP^ ( e2 <= dx )
+ ,err1 LDR^ ,dx LDR^ ADD!^ ,err1 STR^ ( err1 += dx; )
,y_ LDR^ +0001 ADD!^ ,y_ STR^ ( y0 += y0 < y1 ? 1 : -1; )
- @continue2
- ,x_ LDR^ ,x1 LDR^ LTH!^ ,loop ROT JMP? POP^ ( loop )
+ @line-end
+ ,x_ LDR^ ,x1 LDR^ NEQ!^ ,lineloop ROT JMP? POP^ ( loop )
RTS
@redraw
