From 89c2b42bfe15c90e3798132f558551764e6c673a Mon Sep 17 00:00:00 2001
From: hugova <hugova@kth.se>
Date: Tue, 4 Mar 2025 23:01:57 +0100
Subject: [PATCH] Reorginisation of line-drawing code. Also added a macro to
 benchmark line drawing logic. Addition of line_test_time to benchmark line
 drawing time (Do not work yet)

---
 wip-hugo/macros/timer.s                       | 18 ++++
 wip-hugo/routines/line/line.inc               | 11 +++
 wip-hugo/routines/{memory => }/line/line.s    | 11 ++-
 .../routines/{memory => }/line/line_down.s    | 11 +--
 .../{memory => }/line/line_down_inv.s         | 11 +--
 wip-hugo/routines/line/line_test.s            | 90 +++++++++++++++++++
 wip-hugo/routines/line/line_test_time.s       | 38 ++++++++
 wip-hugo/routines/{memory => }/line/line_up.s | 61 ++++++-------
 .../routines/{memory => }/line/line_up_inv.s  | 13 +--
 wip-hugo/source.s                             | 50 ++---------
 10 files changed, 202 insertions(+), 112 deletions(-)
 create mode 100644 wip-hugo/macros/timer.s
 create mode 100644 wip-hugo/routines/line/line.inc
 rename wip-hugo/routines/{memory => }/line/line.s (70%)
 rename wip-hugo/routines/{memory => }/line/line_down.s (90%)
 rename wip-hugo/routines/{memory => }/line/line_down_inv.s (90%)
 create mode 100644 wip-hugo/routines/line/line_test.s
 create mode 100644 wip-hugo/routines/line/line_test_time.s
 rename wip-hugo/routines/{memory => }/line/line_up.s (60%)
 rename wip-hugo/routines/{memory => }/line/line_up_inv.s (87%)

diff --git a/wip-hugo/macros/timer.s b/wip-hugo/macros/timer.s
new file mode 100644
index 0000000..51e5589
--- /dev/null
+++ b/wip-hugo/macros/timer.s
@@ -0,0 +1,18 @@
+;; Max 1.5s
+.macro time_start
+    PHA
+    LDA $DC08 ; Bit 0..3: Tenth seconds in BCD-format, others may be 0 or 1
+    AND #%00001111
+    STA $f1
+    PLA
+.endmacro
+
+.macro time_stop
+    PHA
+    LDA $DC08 ; Bit 0..3: Tenth seconds in BCD-format, others may be 0 or 1
+    AND #%00001111
+    SEC
+    SBC $f1
+    STA $f1
+    PLA
+.endmacro
diff --git a/wip-hugo/routines/line/line.inc b/wip-hugo/routines/line/line.inc
new file mode 100644
index 0000000..8f5777b
--- /dev/null
+++ b/wip-hugo/routines/line/line.inc
@@ -0,0 +1,11 @@
+    ;;Not values but register position in memory
+    X_end = $04
+    Y_end = $05
+    X_pos = $FC
+    Y_pos = $FB
+    dy= $0c
+    dx = dy
+    dy_2 = $0607
+    dx_2 = dy_2
+    V = $0809
+    D = $0a0b
diff --git a/wip-hugo/routines/memory/line/line.s b/wip-hugo/routines/line/line.s
similarity index 70%
rename from wip-hugo/routines/memory/line/line.s
rename to wip-hugo/routines/line/line.s
index 202074c..3e7a289 100644
--- a/wip-hugo/routines/memory/line/line.s
+++ b/wip-hugo/routines/line/line.s
@@ -1,11 +1,16 @@
 .proc line; X_pos =< X_end skall alltid gälla
-    dx = $fe
-    dy = $69
+    ;; note that these have same adresses as stuff in line.inc
+    ;; This should be used as a optimisation in the future
+    dx = $0c
+    dy = $06
     ;;dx
     SEC
     LDA X_end
     SBC X_pos
     STA dx
+    BCC dx_no_underflow;; X_end >= X_pos
+    EOR #$ff ; Fix bit underflow
+    dx_no_underflow:
 
     SEC
     LDA Y_pos
@@ -20,6 +25,7 @@ steep:
     jsr line_up_inv
     RTS
 shallow: ;dy =< dx
+    lda dx
     jsr line_up
     RTS
 down:
@@ -34,7 +40,6 @@ shallow_: ;dy < dx
     jsr line_down
     RTS
 .endproc
-
 .include "line_down.s"
 .include "line_down_inv.s"
 .include "line_up.s"
diff --git a/wip-hugo/routines/memory/line/line_down.s b/wip-hugo/routines/line/line_down.s
similarity index 90%
rename from wip-hugo/routines/memory/line/line_down.s
rename to wip-hugo/routines/line/line_down.s
index 287b8c2..ce1c898 100644
--- a/wip-hugo/routines/memory/line/line_down.s
+++ b/wip-hugo/routines/line/line_down.s
@@ -6,16 +6,7 @@
     ;;#                             *                       #
     ;;#                                (X_end, Y_end)       #
     ;;NOTE THAT X_pos <= X_end, Y_pos <= Y_end. Max 45deg!
-
-    ;;Not values but register position in memory
-    X_end = $04
-    Y_end = $05
-    X_pos = $FC
-    Y_pos = $FB
-    dx = $0c
-    dy_2 = $0607
-    V = $0809
-    D = $0a0b
+    .include "line.inc"; Defines memory positions, ex X_pos
 
     ;;We need to clear this memory
     LDA #$00
diff --git a/wip-hugo/routines/memory/line/line_down_inv.s b/wip-hugo/routines/line/line_down_inv.s
similarity index 90%
rename from wip-hugo/routines/memory/line/line_down_inv.s
rename to wip-hugo/routines/line/line_down_inv.s
index 5ddaf4c..9e5831f 100644
--- a/wip-hugo/routines/memory/line/line_down_inv.s
+++ b/wip-hugo/routines/line/line_down_inv.s
@@ -6,16 +6,7 @@
     ;;#                             *                       #
     ;;#                                (X_end, Y_end)       #
     ;;NOTE THAT X_pos <= X_end, Y_pos <= Y_end. Min 45deg!
-
-    ;;Not values but register position in memory
-    X_end = $04
-    Y_end = $05
-    X_pos = $FC
-    Y_pos = $FB
-    dy = $0c
-    dx_2 = $0607
-    V = $0809
-    D = $0a0b
+    .include "line.inc"; Defines memory positions, ex X_pos
 
     ;example values ~~~~~ SHOULD BE PRECOMPILED
     ;LDA #$00
diff --git a/wip-hugo/routines/line/line_test.s b/wip-hugo/routines/line/line_test.s
new file mode 100644
index 0000000..a2e689a
--- /dev/null
+++ b/wip-hugo/routines/line/line_test.s
@@ -0,0 +1,90 @@
+    X_end = $04
+    Y_end = $05
+    X_pos = $FC
+    Y_pos = $FB
+    ;;for testing stuff
+    Y_pos_ = $0D
+    X_pos_ = $0E
+    Y_end_ = $10
+    X_end_ = $11
+    LDA #$d0
+    STA X_pos_
+    LDA #$60
+    STA Y_pos_
+    LDA #$ff
+    STA X_end
+    LDA #$0
+    STA Y_end
+
+;; Short test for timing
+@loop:
+    LDA Y_pos_
+    STA Y_pos
+    LDA X_pos_
+    STA X_pos
+
+    jsr line
+    INC Y_end
+    LDA Y_end
+    CMP #$bb
+    BEQ end__
+    jmp @loop
+end__:
+
+
+
+;; Full anfle test
+@loop:
+    LDA Y_pos_
+    STA Y_pos
+    LDA X_pos_
+    STA X_pos
+
+    jsr line
+    INC Y_end
+    LDA Y_end
+    CMP #$bb
+    BEQ end
+    jmp @loop
+end:
+;;Long lines
+
+;;Lets cleer bitmap
+LDA #>VIC_bank
+STA $FC
+LDA #<VIC_bank
+STA $FB
+
+LDA #>$5f3f
+STA $FE
+LDA #<$5f3f
+STA $FD
+
+LDA #$0
+jsr memory_rec
+
+LDA #$00
+STA X_pos_
+LDA #$60
+STA Y_pos_
+LDA #$ff
+STA X_end
+LDA #$0
+STA Y_end
+@loop:
+    LDA Y_pos_
+    STA Y_pos
+    LDA X_pos_
+    STA X_pos
+
+    jsr line
+    INC Y_end
+    LDA Y_end
+    CMP #$bb
+    BEQ end_
+    jmp @loop
+end_:
+jmp exit
+
+.include "line.s"
+.include "macros/"
diff --git a/wip-hugo/routines/line/line_test_time.s b/wip-hugo/routines/line/line_test_time.s
new file mode 100644
index 0000000..d45d553
--- /dev/null
+++ b/wip-hugo/routines/line/line_test_time.s
@@ -0,0 +1,38 @@
+    X_end = $04
+    Y_end = $05
+    X_pos = $FC
+    Y_pos = $FB
+    ;;for testing stuff
+    Y_pos_ = $0D
+    X_pos_ = $0E
+    Y_end_ = $10
+    X_end_ = $11
+    LDA #$d0
+    STA X_pos_
+    LDA #$60
+    STA Y_pos_
+    LDA #$ff
+    STA X_end
+    LDA #$0
+    STA Y_end
+
+;; Short test for timing
+time_start
+
+@loop:
+    LDA Y_pos_
+    STA Y_pos
+    LDA X_pos_
+    STA X_pos
+
+    jsr line
+    INC Y_end
+    LDA Y_end
+    CMP #$30
+    BEQ end__
+    jmp @loop
+end__:
+time_stop
+jmp exit
+
+.include "line.s"
diff --git a/wip-hugo/routines/memory/line/line_up.s b/wip-hugo/routines/line/line_up.s
similarity index 60%
rename from wip-hugo/routines/memory/line/line_up.s
rename to wip-hugo/routines/line/line_up.s
index 310d8dd..3d7f2b4 100644
--- a/wip-hugo/routines/memory/line/line_up.s
+++ b/wip-hugo/routines/line/line_up.s
@@ -7,16 +7,7 @@
     ;;# (X_pos, Y_pos)                                      #
     ;;
     ;;NOTE THAT X_pos <= X_end, Y_pos >= Y_end. Max 45deg!
-
-    ;;Not values but register position in memory
-    X_end = $04
-    Y_end = $05
-    X_pos = $FC
-    Y_pos = $FB
-    dy_2 = $0607
-    dx = $0c
-    V = $0809
-    D = $0a0b
+    .include "line.inc"; Defines memory positions, ex X_pos
 
     ;;example values ~~~~~ SHOULD BE PRECOMPILED
     ;LDA #$90
@@ -35,32 +26,34 @@
     STA $FD ; for pixel_draw
 
     ;; V = 2*(dx -dy)
-     ;; where: dy = Y_pos - Y_end, dx = X_end - X_start
-     LDA Y_pos
-     SEC
-     SBC Y_end
-     STA >V
-     STA >dy_2;  >dy_2 = dy. Needed for dy_2 (not for V)
-     LDA X_end
-     SEC
-     SBC X_pos
-     STA dx
-     SEC
-     SBC >V
-     STA >V; <V = dx - dy
-     mult_16 >V, <V; V = 2*(dx -dy)
+    ;; where: dy = Y_pos - Y_end, dx = X_end - X_start
+    ;; This logic is comented out because line.s does it woithout any
+    ;;extra cost. May be needed in the future so it will stay as coments!
+    LDA Y_pos
+    SEC
+    SBC Y_end
+    STA >V
+    STA >dy_2;  >dy_2 = dy. Needed for dy_2 (not for V)
+    LDA X_end
+    SEC
+    SBC X_pos
+    STA dx
+    SEC
+    SBC >dy_2
+    STA >V; <V = dx - dy
+    mult_16 >V, <V; V = 2*(dx -dy)
 
-     ;dy_2 = dy*2
-     mult_16 >dy_2, <dy_2
+    ;dy_2 = dy*2
+    mult_16 >dy_2, <dy_2
 
-     ;;D = 2*dy - dx + 2*255
-     ;;Our D is bigger then wikipedia because D is unsigned.
-     LDA >dy_2
-     STA >D
-     LDA <dy_2
-     STA <D
-     Add_16 >D, <D, #$ff, #$01
-     Sub_16 >D, <D, dx, #$00
+    ;;D = 2*dy - dx + 2*255
+    ;;Our D is bigger then wikipedia because D is unsigned.
+    LDA >dy_2
+    STA >D
+    LDA <dy_2
+    STA <D
+    Add_16 >D, <D, #$ff, #$01
+    Sub_16 >D, <D, dx, #$00
 for_x:
     jsr pixel_draw
     ;;Increment X until X_pos = X_end and Y_pos = Y_end
diff --git a/wip-hugo/routines/memory/line/line_up_inv.s b/wip-hugo/routines/line/line_up_inv.s
similarity index 87%
rename from wip-hugo/routines/memory/line/line_up_inv.s
rename to wip-hugo/routines/line/line_up_inv.s
index 57deeff..d976498 100644
--- a/wip-hugo/routines/memory/line/line_up_inv.s
+++ b/wip-hugo/routines/line/line_up_inv.s
@@ -6,18 +6,9 @@
     ;;#                *                                    #
     ;;# (X_pos, Y_pos)                                      #
    ;;NOTE THAT Y_pos >) Y_end, X_pos <= X_end. Min 45deg!
+   .include "line.inc"
 
-    ;;Not values but register position in memory
-    X_end = $04
-    Y_end = $05
-    X_pos = $FC
-    Y_pos = $FB
-    dx_2 = $0607
-    dy = $0c
-    V = $0809
-    D = $0a0b
-
-    ;We need to clear this memory
+   ;;We need to clear this memory
     LDA #$00
     STA <V
     STA <dx_2
diff --git a/wip-hugo/source.s b/wip-hugo/source.s
index 8cf7114..47b370b 100755
--- a/wip-hugo/source.s
+++ b/wip-hugo/source.s
@@ -1,50 +1,12 @@
-.include "STARTUP.s"
 .include "macros/16aritmatic.s"
+.include "macros/timer.s"
 
-    X_end = $04
-    Y_end = $05
-    X_pos = $FC
-    Y_pos = $FB
+.include "STARTUP.s"
+.include "routines/line/line_test_time.s"
 
-    ;;for testing stuff
-    Y_pos_ = $0D
-    X_pos_ = $0E
-    Y_end_ = $10
-    X_end_ = $11
+;;This is used by .s files to terminate nicely without reading includes at the end!
+exit:
+jmp exit
 
-    LDA #$d0
-    STA X_pos_
-    LDA #$60
-    STA Y_pos_
-    LDA #$ff
-    STA X_end_
-    LDA #$0
-    STA Y_end_
-
-@loop:
-    LDA Y_pos_
-    STA Y_pos
-    LDA X_pos_
-    STA X_pos
-    LDA Y_end_
-    STA Y_end
-    LDA X_end_
-    STA X_end
-
-    jsr line
-    INC Y_end_
-    LDA Y_end_
-    CMP #$bb
-    BEQ loop
-    jmp @loop
-loop:
-    jmp loop
-
-
-
-
-loop_:
-jmp loop_
 .include "routines/memory/memory_rec.s"
 .include "routines/memory/pixel_draw.s"
-.include "routines/memory/line/line.s"