From 60ffe8b76ef991c6c495fb9b51446d10e3676a4a Mon Sep 17 00:00:00 2001
From: Vince Weaver <vince@deater.net>
Date: Wed, 6 Dec 2023 23:59:11 -0500
Subject: [PATCH] twister: add lores version

---
 graphics/gr/twister/Makefile  | 11 +++++++++--
 graphics/gr/twister/lores.bas | 20 ++++++++++++++++++++
 2 files changed, 29 insertions(+), 2 deletions(-)
 create mode 100644 graphics/gr/twister/lores.bas

diff --git a/graphics/gr/twister/Makefile b/graphics/gr/twister/Makefile
index 8c65a871..20eb3656 100644
--- a/graphics/gr/twister/Makefile
+++ b/graphics/gr/twister/Makefile
@@ -9,10 +9,11 @@ EMPTY_DISK = ../../../empty_disk
 
 all:	twister.dsk
 
-twister.dsk:	$(DOS33) HELLO TWISTER.BAS
+twister.dsk:	$(DOS33) HELLO TWISTER.BAS LORES.BAS
 	cp $(EMPTY_DISK)/empty.dsk twister.dsk
 	$(DOS33) -y twister.dsk SAVE A HELLO
 	$(DOS33) -y twister.dsk SAVE A TWISTER.BAS
+	$(DOS33) -y twister.dsk SAVE A LORES.BAS
 
 ###
 
@@ -24,9 +25,15 @@ HELLO:	hello.bas
 TWISTER.BAS:	twister.bas
 	$(TOKENIZE) < twister.bas > TWISTER.BAS
 
+###
+
+LORES.BAS:	lores.bas
+	$(TOKENIZE) < lores.bas > LORES.BAS
+
+
 
 ###
 
 clean:	
-	rm -f *~ *.o HELLO TWISTER.BAS *.lst
+	rm -f *~ *.o HELLO TWISTER.BAS LORES.BAS *.lst
 
diff --git a/graphics/gr/twister/lores.bas b/graphics/gr/twister/lores.bas
new file mode 100644
index 00000000..c353b85a
--- /dev/null
+++ b/graphics/gr/twister/lores.bas
@@ -0,0 +1,20 @@
+10 REM TWISTER-DEMO
+15 REM https://8bitshack.org/post/twister/
+20 GR
+30 FOR A2 = 1 TO 360 STEP 3
+40 AM = 120+COS(A2*0.0174533)*100
+50 AN = -3.141593+SIN(A2*0.0174533)*3.141593
+60 FOR Y = 1 TO 39
+65 FV = Y*4/AM+AN
+70 X1 = 5*SIN(FV)
+80 X2 = 5*SIN(FV+1.570796)
+95 X3 = -X1
+105 X4 = -X2
+108 COLOR = 0: HLIN 105/7,175/7 AT Y
+110 IF X1 < X2 THEN COLOR = 1: HLIN 20+X1,20+X2 AT Y: GOTO 130
+120 IF X3 < X4 THEN COLOR = 1: HLIN 20+X3,20+X4 AT Y
+130 IF X2 < X3 THEN COLOR = 2: HLIN 20+X2,20+X3 AT Y: GOTO 150
+140 IF X4 < X1 THEN COLOR = 2: HLIN 20+X4,20+X1 AT Y
+150 NEXT Y
+160 NEXT A2
+170 GOTO 30