Merge pull request #217 from boriel/feature/fastplot

Add fastplot library

Author: boriel

library/fastplot.bas

@@ -0,0 +1,139 @@
+' ----------------------------------------------------------------
+' This file is released under the MIT License
+'
+' Copyleft (k) 2019
+' Contributed by Britlion and rearranged by John Mcgibbitts
+' ----------------------------------------------------------------
+
+
+#ifndef __LIBRARY_FASTPLOT__
+REM Avoid recursive / multiple inclusion
+#define __LIBRARY_FASTPLOT__
+
+#pragma push(case_insensitive)
+#pragma case_insensitive = True
+
+
+' ----------------------------------------------------------------
+' Plots a point at (x, y) in OVER 1 mode (XOR) with color as ATTR
+' This routine is slightly faster than PLOT XOR 1 with ATTRs
+' ----------------------------------------------------------------
+SUB fastcall fastPlotXORAttr (x AS UBYTE, y AS UBYTE, color AS UBYTE)
+ASM
+    pop hl
+    pop de
+    ex (sp), hl
+    ld c, h
+
+    ld e, a
+    ld a, 191
+    sub d 
+    ld d, a
+    ret c
+
+    AND a
+    rra
+    scf
+    rra
+    AND a
+    rra
+    XOR d
+    AND 248
+    XOR d
+    ld h, a
+    ld a, e
+    rlca
+    rlca
+    rlca
+    XOR d
+    AND 199
+    XOR d
+    rlca
+    rlca
+    ld l, a
+
+    ld a, e
+    AND 7
+    ld b, a
+    inc b
+    ld a, 254
+
+plotPointXORAttr_loop:
+    rrca
+    djnz plotPointXORAttr_loop
+
+    cpl
+    xor (hl)
+    ld (hl), a
+
+plotPointXORAttr_end: ; ' Point plotted.
+    ld a, h ; ' HL = addr of attr
+    rrca
+    rrca
+    rrca
+    and $03
+    or $58
+    ld h, a ; ' HL = addr of attr
+
+    ld (hl),c
+END ASM
+END SUB
+
+
+' ----------------------------------------------------------------
+' Plots a point at (x, y) in OVER 1 mode (XOR) with color as ATTR
+' This routine is slightly faster than PLOT XOR 1
+' ----------------------------------------------------------------
+SUB fastcall fastPlotXOR(x AS UBYTE, y AS UBYTE)
+ASM
+    pop hl
+    ex (sp), hl
+
+    ld e, a
+    ld a, 191
+    sub h
+    ld d, a
+    ret c
+
+    AND a
+    rra
+    scf
+    rra
+    AND a
+    rra
+    XOR d
+    AND 248
+    XOR d
+    ld h, a
+    ld a, e
+    rlca
+    rlca
+    rlca
+    XOR d
+    AND 199
+    XOR d
+    rlca
+    rlca
+    ld l, a
+
+    ld a, e
+    AND 7
+    ld b, a
+    inc b
+    ld a, 254
+
+plotPointXORAttr_loop:
+    rrca
+    djnz plotPointXORAttr_loop
+
+    cpl
+    xor (hl)
+    ld (hl), a
+
+END ASM
+END SUB
+
+
+#pragma pop(case_insensitive)
+
+#endif