Update lifes left for player 1

The whole handling of player 2 will come whenever I set to implement
multi-player for this game.

Signed-off-by: Miquel Sabaté Solà <mssola@mssola.com>

4 files changed, 52 insertions, 2 deletions

diff --git a/src/driver.s b/src/driver.s
index 8a0d452..b90cabe 100644
--- a/src/driver.s
+++ b/src/driver.s
@@ -80,6 +80,14 @@
         lda #PLAYER_TIMER_VALUE
         sta zp_player_timer
 
+        ;; Initialize lifes for both players.
+        lda #4
+        sta Player::zp_lifes
+        sta Player::zp_lifes + 1
+        lda Player::zp_state
+        ora #%00001000
+        sta Player::zp_state
+
         ;; Mark the state of the game as "game". That is, the player has
         ;; started. Also set the `ppu` flag and unset the `title over` one.
         lda #%01000001
diff --git a/src/interrupts.s b/src/interrupts.s
index 8c53af7..b5120b4 100644
--- a/src/interrupts.s
+++ b/src/interrupts.s
@@ -34,6 +34,28 @@
         jsr Driver::pal_handler
     .endif
 
+    ;; Do we need to update the lifes from players on the HUD?
+    lda Player::zp_state
+    and #%00001000
+    beq @global_flags
+
+    ;; Yeah! TODO: this is only done for player 1.
+    bit PPU::m_status
+    lda #$28
+    sta PPU::m_address
+    lda #$4B
+    sta PPU::m_address
+    lda Player::zp_lifes
+    clc
+    adc #$10
+    sta PPU::m_data
+
+    ;; And unset the 'life' flag from the player.
+    lda Player::zp_state
+    and #%11110111
+    sta Player::zp_state
+
+@global_flags:
     ;; TODO: some actions here will depend on the status of the game...
     lda Globals::zp_flags
     and #%00000001
diff --git a/src/jetpac.s b/src/jetpac.s
index b6b44e2..2e55771 100644
--- a/src/jetpac.s
+++ b/src/jetpac.s
@@ -122,6 +122,7 @@
     sta Globals::zp_flags
     sta Joypad::zp_buttons1
     sta Joypad::zp_buttons2
+    sta Player::zp_state
 
     ;; Initialize the level. We allow the build system to pass its own value for
     ;; this in `LEVEL`, just in case we want to debug the enemy of a specific
diff --git a/src/player.s b/src/player.s
index a821f0e..73ff20e 100644
--- a/src/player.s
+++ b/src/player.s
@@ -86,7 +86,8 @@
     ;; |-----+------------+-----------------------------------------------|
     ;; |   7 | thrust     | Player is hitting the thrust                  |
     ;; |   6 | heading    | heading right                                 |
-    ;; | 5-3 | -          | Unused                                        |
+    ;; | 5-4 | -          | Unused                                        |
+    ;; |   3 | life       | Lifes should be updated on screen             |
     ;; |   2 | update     | Sprite (animation or heading) must be updated |
     ;; | 1-0 | walk       | 0: still; 1: animation 1; 2: animation 2      |
     zp_state = $50
@@ -102,6 +103,9 @@
         zp_step_on_pal = $52
     .endif
 
+    ;; Lifes for both players.
+    zp_lifes = $53              ; asan:reserve $02
+
     ;; How many animations are there for walking?
     WALK_ANIMATION_NR = 3
 
@@ -830,7 +834,13 @@
 
     ;; That's just german for "the Bart, the".
     .proc die_bart_die
-        ;; TODO: dec lifes
+        ;; Decrement the life.
+        ;; TODO: this is just considering the first player only!.
+        dec Player::zp_lifes
+        beq @over
+        lda Player::zp_state
+        ora #%00001000
+        sta Player::zp_state
 
         ;; Move the player's sprites out of the screen.
         ldx #0
@@ -853,5 +863,14 @@
         lda Player::zp_screen_x
         sta Globals::zp_arg3
         JAL Explosions::create
+
+    @over:
+        ;; Set the proper flag for game over.
+        ;; TODO: game over (coin)
+        lda Globals::zp_flags
+        ora #%00000010
+        sta Globals::zp_flags
+
+        rts
     .endproc
 .endscope