Fixed game menu. Fixed jerky mouse movement while scanning keyboard (cause was scanning keyboard right before reading mouse). Menu code tighter.

2026-01-11 21:00:08 +01:00 · 2026-01-11 21:00:08 +01:00 · f4bff18f29
commit f4bff18f29
parent a799d7695c
3 changed files with 152 additions and 135 deletions
--- a/gameloop.c65
+++ b/gameloop.c65
@ -930,7 +930,13 @@ FUNC game_loop
      WHILE vic_raster != 250
      WEND

-      // Check for menu key (Return or Left Arrow)
+      // Read mouse input FIRST (before keyboard scan)
+      // Per Commodore 1351 manual: keyboard scan lines affect POT registers
+      // so mouse must be read before keyboard to avoid interference
+      mouse_read()
+      pointer_update_mouse(mouse_delta_x, mouse_delta_y)
+
+      // Check for menu key (Return or Left Arrow) AFTER mouse
      key_scan(menu_key)
      IF menu_key == KEY_RETURN
        menu_show(menu_action)
@ -943,10 +949,6 @@ FUNC game_loop
        render_all_piles_initial()
      ENDIF

-      // Read mouse input (Port 1)
-      mouse_read()
-      pointer_update_mouse(mouse_delta_x, mouse_delta_y)
-
      // Read joystick input (Port 2)
      joy_read_port2()
      pointer_update_joystick(joy_state)
--- a/gamemenu.c65
+++ b/gamemenu.c65
@ -149,53 +149,34 @@ FEND
 // Render the full menu screen with current settings
 // ============================================================================
 FUNC menu_render
-  WORD screen_pos
-  WORD str_ptr
-
  // Clear screen
  fill_mem($0400, $0400+999, 32)  // 32 = space character
  fill_mem($D800, $D800+999, 14)  // Light blue text

  // Title (centered at row 2)
-  screen_pos = 2*40+$0400+8
-  POINTER str_ptr -> str_title
-  menu_print_string(screen_pos, str_ptr)
+  menu_print_string(2*40+$0400+8, @str_title)

  // Draw mode option (row 6)
-  screen_pos = 6*40+$0400+4
-  POINTER str_ptr -> str_draw_mode
-  menu_print_string(screen_pos, str_ptr)
+  menu_print_string(6*40+$0400+4, @str_draw_mode)

  // Draw mode value and indicators
  menu_update_draw_mode()

  // Foundation to Tableau option (row 9)
-  screen_pos = 9*40+$0400+4
-  POINTER str_ptr -> str_found_to_tab
-  menu_print_string(screen_pos, str_ptr)
+  menu_print_string(9*40+$0400+4, @str_found_to_tab)

  // Foundation to Tableau value
  menu_update_found_to_tab()

-  // Instructions for resume/restart (row 14+)
-  screen_pos = 12*40+$0400+4
-  POINTER str_ptr -> str_inst_f7
-  menu_print_string(screen_pos, str_ptr)
+  // Instructions for resume/restart (row 12+)
+  menu_print_string(12*40+$0400+4, @str_inst_f7)
+  menu_print_string(15*40+$0400+4, @str_inst_runstop)

-  screen_pos = 15*40+$0400+4
-  POINTER str_ptr -> str_inst_f8
-  menu_print_string(screen_pos, str_ptr)
+  // Controls info (row 20)
+  menu_print_string(20*40+$0400+2, @str_controls)

-  // License (row 23, centered)
-  screen_pos = 20*40+$0400+2
-  POINTER str_ptr -> str_controls
-  menu_print_string(screen_pos, str_ptr)
-
-
-  // License (row 23, centered)
-  screen_pos = 23*40+$0400+1
-  POINTER str_ptr -> str_license
-  menu_print_string(screen_pos, str_ptr)
+  // License (row 23)
+  menu_print_string(23*40+$0400+1, @str_license)

  // Set border color to menu color (purple)
  POKE $d020 , 4
@ -280,8 +261,8 @@ FUNC menu_show(out:{BYTE action})
            action = MENU_ACTION_RESUME
            BREAK

-          CASE KEY_F8
-            // Restart game (SHIFT+F7)
+          CASE KEY_RUNSTOP
+            // Restart game
            action = MENU_ACTION_RESTART
            BREAK
        ENDSWITCH
@ -364,9 +345,9 @@ ASM
  !scr "F7: Resume game", 0
 ENDASM

-LABEL str_inst_f8
+LABEL str_inst_runstop
 ASM
-  !scr "F8: Restart game", 0
+  !scr "Run/Stop: Restart game", 0
 ENDASM

 LABEL str_controls
--- a/keyboard.c65
+++ b/keyboard.c65
@ -8,10 +8,14 @@ GOTO __skip_lib_keyboard
 // KEYBOARD INPUT DRIVER FOR COMMODORE 64
 // ============================================================================
 // Direct CIA keyboard matrix reading (no IRQ required)
+// Uses non-interfering keyboard scan technique to avoid conflicts with
+// joysticks on ports 1 and 2.
 //
-// C64 Keyboard Matrix:
-//   $DC00 (Port A): Column select (write, active-low)
-//   $DC01 (Port B): Row read (read, active-low)
+// Based on code from:
+// https://codebase64.c64.org/doku.php?id=base:scanning_the_keyboard_without_joysticks_interfere
+//
+// This method converts keycodes to row/column values and performs double-check
+// scanning to ensure joystick inputs don't interfere with keyboard detection.
 //
 // Usage:
 //   #INCLUDE "keyboard.c65"
@ -23,11 +27,6 @@ GOTO __skip_lib_keyboard
 //     CASE KEY_F3
 //       // handle F3
 //   ENDSWITCH
-//
-//   // Debouncing: wait for KEY_NONE
-//   WHILE key != KEY_NONE
-//     key_scan(key)
-//   WEND
 // ============================================================================

 // CIA Port addresses
@ -36,118 +35,153 @@ WORD CONST CIA_PORTB = $DC01     // Port B - COLUMN reading (read)
 WORD CONST CIA_DDRA = $DC02      // Port A Data Direction Register
 WORD CONST CIA_DDRB = $DC03      // Port B Data Direction Register

-// Key constants
+// Key constants (returned by key_scan)
 BYTE CONST KEY_NONE = 0
 BYTE CONST KEY_F1 = 1
 BYTE CONST KEY_F3 = 2
 BYTE CONST KEY_F7 = 3
-BYTE CONST KEY_F8 = 4       // F7 + SHIFT
+BYTE CONST KEY_RUNSTOP = 4
 BYTE CONST KEY_RETURN = 5
-BYTE CONST KEY_LEFT_ARROW = 6
+
+// C64 Keycode constants (for internal use)
+// Based on: https://www.c64-wiki.com/wiki/Keyboard
+BYTE CONST KEYCODE_RETURN = $01
+BYTE CONST KEYCODE_F7F8 = $03
+BYTE CONST KEYCODE_F1F2 = $04
+BYTE CONST KEYCODE_F3F4 = $05
+BYTE CONST KEYCODE_RUNSTOP = $3F
+
+// Row and column lookup tables for keyboard scanning
+LABEL key_row_table
+ASM
+  !8 $FE, $FD, $FB, $F7, $EF, $DF, $BF, $7F
+ENDASM
+
+LABEL key_column_table
+ASM
+  !8 $01, $02, $04, $08, $10, $20, $40, $80
+ENDASM
+
+// Key history for debouncing (one byte per tracked key)
+BYTE key_history_f1
+BYTE key_history_f3
+BYTE key_history_f7
+BYTE key_history_return
+BYTE key_history_runstop
+
+// ============================================================================
+// FUNC key_check_raw
+// Low-level keyboard check for a specific keycode
+// Uses non-interfering scan method with double-check to avoid joystick conflicts
+// Returns: result = 1 if pressed, 0 if not pressed
+// This comes from here:
+// https://codebase64.c64.org/doku.php?id=base:scanning_the_keyboard_without_joysticks_interfere
+// ============================================================================
+FUNC key_check_raw({BYTE keycode} io:{BYTE histv} out:{BYTE result})
+  ASM
+    lda |keycode|
+    pha
+    lsr
+    lsr
+    lsr
+    tay
+    lda key_row_table,y
+    sta $dc00
+    pla
+    and #$07
+    tay
+    lda $dc01
+    and key_column_table,y
+    bne _nokey
+    lda #$ff        ; key is checked 2nd time, to be sure
+    sta $dc00       ; joy #1 and #2 are not interfering
+    lda $dc01
+    and key_column_table,y
+    beq _nokey
+
+    cmp |histv|     ; history value?
+    bne _newkey
+    clc             ; case #3, key is held down. keep history & set C=0
+    bcc _backy
+
+_nokey
+    asl             ; case #1, no keypress, update history value 2x & set C=0
+    clc
+    !byte $24       ; BIT zero page - skips next 2-byte instruction
+_newkey
+    sec             ; case #2, key pressed&released. update history & set C=1
+    sta |histv|
+
+_backy
+    lda #$ff
+    sta $dc00       ; set default value
+    lda #$7f
+    sta $dc01       ; set default value
+
+    ; Convert carry flag to result: C=1 -> pressed (1), C=0 -> not pressed (0)
+    lda #0
+    rol             ; shift carry into bit 0
+    sta |result|
+  ENDASM
+FEND
+

 // ============================================================================
 // FUNC key_scan
 // Scan keyboard and return which key is pressed
 // Returns KEY_* constant (KEY_NONE if no relevant key pressed)
-// C64 Keyboard Matrix:
-// - Write to $DC00 (Port A) to select ROW
-// - Read from $DC01 (Port B) to detect COLUMN
+// Uses non-interfering keyboard scan to avoid joystick conflicts
 // ============================================================================
 FUNC key_scan(out:{BYTE key_pressed})
-  BYTE col_data
-  BYTE temp
-  BYTE shift_held
-  BYTE saved_ddra
-  BYTE saved_ddrb
-  BYTE saved_porta
-  BYTE row0_data
-  BYTE row1_data
-  BYTE row6_data
+  BYTE check_result

  key_pressed = KEY_NONE
-  shift_held = 0
-
-  // Save current DDR state
-  saved_ddra = PEEK CIA_DDRA
-  saved_ddrb = PEEK CIA_DDRB
-  saved_porta = PEEK CIA_PORTA

  // Set up DDR: Port A = output (rows), Port B = input (columns)
-  POKE CIA_DDRA , $FF
-  POKE CIA_DDRB , $00
+  ASM
+    lda #$ff
+    sta $dc02  // CIA_DDRA
+    lda #$00
+    sta $dc03  // CIA_DDRB
+  ENDASM

-  // Check F8 FIRST with two-read atomic check
-  // Read 1: Select rows 0+1+6 simultaneously ($BC = 10111100)
-  POKE CIA_PORTA , $BC
-  BYTE multi_row_data
-  multi_row_data = PEEK CIA_PORTB
-
-  // Read 2: Select ONLY row 0 ($FE = 11111110)
-  POKE CIA_PORTA , $FE
-  col_data = PEEK CIA_PORTB
-
-  // F8 detection: F7 pressed AND SHIFT pressed
-  // F7 at Row 0, Col 3 - check in row0 data
-  temp = col_data & $08
-  IF temp == 0
-    // F7 is pressed, now check if real SHIFT is pressed
-    // Compare multi-row read vs row-0-only read for cols 4 and 7
-    // If col 4 or 7 was low in multi-row but NOT in row-0-only, it's SHIFT
-    BYTE shift_cols
-    shift_cols = multi_row_data & $90  // Cols 4 and 7 in multi-row read
-    temp = col_data & $90              // Cols 4 and 7 in row 0 only read
-    // If multi-row has a low bit that row-0-only doesn't, it's from rows 1 or 6 (SHIFT)
-    IF shift_cols != temp
-      key_pressed = KEY_F8
-    ENDIF
+  // Check F1
+  key_check_raw(KEYCODE_F1F2, key_history_f1, check_result)
+  IF check_result > 0
+    key_pressed = KEY_F1
  ENDIF

-  // If not F8, check other Row 0 keys (col_data already has row 0 from above)
+  // Check F3
  IF key_pressed == KEY_NONE
-
-    // Check F1 (Row 0, Column 4)
-    temp = col_data & $10
-    IF temp == 0
-      key_pressed = KEY_F1
-    ENDIF
-
-    // Check F3 (Row 0, Column 5)
-    IF key_pressed == KEY_NONE
-      temp = col_data & $20
-      IF temp == 0
-        key_pressed = KEY_F3
-      ENDIF
-    ENDIF
-
-    // Check F7 (Row 0, Column 3)
-    IF key_pressed == KEY_NONE
-      temp = col_data & $08
-      IF temp == 0
-        key_pressed = KEY_F7
-      ENDIF
-    ENDIF
-
-    // Check RETURN (Row 0, Column 1)
-    IF key_pressed == KEY_NONE
-      temp = col_data & $02
-      IF temp == 0
-        key_pressed = KEY_RETURN
-      ENDIF
-    ENDIF
-
-    // Check Left Arrow (Row 0, Column 7)
-    IF key_pressed == KEY_NONE
-      temp = col_data & $80
-      IF temp == 0
-        key_pressed = KEY_LEFT_ARROW
-      ENDIF
+    key_check_raw(KEYCODE_F3F4, key_history_f3, check_result)
+    IF check_result > 0
+      key_pressed = KEY_F3
    ENDIF
  ENDIF

-  // Always restore saved DDR and port state
-  POKE CIA_PORTA , saved_porta
-  POKE CIA_DDRA , saved_ddra
-  POKE CIA_DDRB , saved_ddrb
+  // Check F7
+  IF key_pressed == KEY_NONE
+    key_check_raw(KEYCODE_F7F8, key_history_f7, check_result)
+    IF check_result > 0
+      key_pressed = KEY_F7
+    ENDIF
+  ENDIF
+
+  // Check RUN/STOP
+  IF key_pressed == KEY_NONE
+    key_check_raw(KEYCODE_RUNSTOP, key_history_runstop, check_result)
+    IF check_result > 0
+      key_pressed = KEY_RUNSTOP
+    ENDIF
+  ENDIF
+
+  // Check RETURN
+  IF key_pressed == KEY_NONE
+    key_check_raw(KEYCODE_RETURN, key_history_return, check_result)
+    IF check_result > 0
+      key_pressed = KEY_RETURN
+    ENDIF
+  ENDIF
 FEND