Collision detection

plat.s

@@ -327,25 +327,40 @@ gamepad_poll:
 .segment "RODATA"
 
 level:
-.byte 0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1
-.byte 0,1,0,0,1,0,0,0,0,0,0,0,1,1,1,1
-.byte 0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1
-.byte 0,1,0,0,1,0,0,0,0,0,0,0,1,1,1,1
-.byte 0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0
 .byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+.byte 0,1,0,0,1,0,0,0,0,1,0,0,2,7,7,3
+.byte 0,0,0,0,0,0,0,0,0,1,0,0,6,0,0,9
+.byte 0,1,0,0,1,0,0,0,0,1,0,0,6,0,0,9
+.byte 0,0,1,1,0,0,0,0,0,1,0,0,4,8,8,5
+.byte 0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0
 .byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
 .byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
 .byte 0,0,0,0,1,1,1,1,1,0,0,0,0,0,0,0
+.byte 0,0,0,0,0,0,0,0,0,0,1,0,1,0,1,0
+.byte 0,0,0,0,0,0,0,0,0,0,0,1,0,1,0,0
+.byte 0,0,0,0,0,0,0,0,0,0,1,0,1,0,1,0
+.byte 0,0,1,0,0,0,0,1,0,0,0,1,0,1,0,0
+.byte 0,1,2,3,4,5,6,7,8,9,0,0,0,0,0,0
 .byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
-.byte 0,0,0,0,0,0,0,0,1,0,1,0,1,0,0,0
+
-.byte 0,0,0,0,0,0,0,0,0,1,0,1,0,0,0,0
+block_x: .res 1
-.byte 0,0,0,0,0,0,0,0,1,0,1,0,1,0,0,0
+block_y: .res 1
-.byte 0,0,0,0,0,0,0,0,0,1,0,1,0,0,0,0
+block_w: .res 1
-.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+block_h: .res 1
 
 metatiles:
 .byte 0,0,0,0,0
-.byte 3,4,5,6,1
+.byte $14,$15,$16,$17,1 ; Full block
+.byte $14,$18,$1B,$0,1 ; up / left
+.byte $18,$15,$0,$19,1 ; up / right
+.byte $1B,$0,$16,$1A,1 ; down / left
+.byte $0,$19,$1A,$17,1 ; down / right
+.byte $1B,$0,$1B,$0,1 ; left
+.byte $18,$18,$0,$0,1 ; up
+.byte $0,$0,$1A,$1A,1 ; down
+.byte $0,$19,$0,$19,1 ; right
+.byte 3,3,3,3,0
+.byte 3,4,5,6,0
 
 example_palette:
 .byte $0F,$00,$3D,$20 ; greyscale
@@ -385,6 +400,7 @@ var_p:    .res 1
 jump_pressed_last_frame: .res 1
 
 frame_counter: .res 1
+last_frame_jumped: .res 1
 
 .segment "CODE"
 main:
@@ -405,6 +421,7 @@ main:
 
     lda #0
     sta frame_counter
+    sta last_frame_jumped
 
     jsr init_objects
 @loop:
@@ -526,6 +543,14 @@ init_objects:
     sta player_vel_y
     sta player_status
 
+    lda #64
+    sta block_x
+    sta block_y
+
+    lda #16
+    sta block_w
+    sta block_h
+
     rts
 
 draw:
@@ -554,7 +579,7 @@ movement:
     cmp #0
     beq :+
         ldx #1
-        lda #3
+        lda #2
         sta player_vel_x
 
         lda player_status
@@ -566,7 +591,7 @@ movement:
     cmp #0
     beq :+
         ldx #1
-        lda #253
+        lda #254
         sta player_vel_x
 
         lda player_status
@@ -607,9 +632,12 @@ movement:
     beq @fail_jump ; If jump last frame, forget it
 
     ; Jump newly pressed this frame
-    lda #250
+    lda #249
     sta player_vel_y
 
+    lda frame_counter
+    sta last_frame_jumped
+
     @fail_jump:
     
     jsr btn_a
@@ -618,7 +646,9 @@ movement:
 
     ; Gravity
     lda frame_counter
-    and #1
+    sec
+    sbc last_frame_jumped
+    and #%00000001
     cmp #0
     bne :+
         lda player_vel_y
@@ -633,6 +663,31 @@ movement:
     adc player_vel_y
     sta player_pos_y
 
+    ; Apply X velocity
+    lda player_pos_x
+    clc
+    adc player_vel_x
+    sta player_pos_x
+
+    ; load x pos, filter blocks, check up and down
+    
+    lda player_vel_y
+    cmp #0
+    bmi :+ ; branch if moving up
+        jsr downward_collision_check
+        jsr left_collision_check
+        jsr right_collision_check
+        jsr upward_collision_check
+        jmp :++
+    :
+        jsr upward_collision_check
+        jsr left_collision_check
+        jsr right_collision_check
+        jsr downward_collision_check
+    :
+
+    rts
+
     ; Keep grounded
     cmp #200
     bcc :+
@@ -641,7 +696,6 @@ movement:
         lda #200
         sta player_pos_y
     :
-
     ; Bonk
     lda #8
     cmp player_pos_y
@@ -652,13 +706,6 @@ movement:
         sta player_pos_y
     :
 
-    ; Apply X velocity
-    lda player_pos_x
-    clc
-    adc player_vel_x
-    sta player_pos_x
-
-
     rts
 
 update_background:
@@ -1012,3 +1059,281 @@ btn_a:
     lsr
     rts
 
+downward_collision_check:
+    lda #0
+    sta var_n
+    @begin_check:
+    lda player_pos_x
+    ldx var_n
+    cpx #0
+    bne :+
+        sec
+        sbc #6
+        jmp :++
+    :
+        clc
+        adc #5
+    :
+    ; divide by 16
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    sta temp_x
+
+    lda player_pos_y
+    ; divide by 16
+    clc
+    adc #8
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    tay
+
+    lda #16
+    jsr mul_y
+    adc temp_x
+    tax
+    lda level, X
+    cmp #0
+    beq :+
+        tya
+        asl
+        asl
+        asl
+        asl
+        sec
+        sbc #8
+        cmp player_pos_y
+        bcs :+
+        sta player_pos_y
+        lda #0
+        sta player_vel_y
+    :
+
+    ldx var_n
+    inx
+    stx var_n
+    cpx #1
+    beq @begin_check
+
+    rts
+
+upward_collision_check:
+    lda #0
+    sta var_n
+    @begin_check:
+    lda player_pos_x
+    ldx var_n
+    cpx #0
+    bne :+
+        sec
+        sbc #6
+        jmp :++
+    :
+        clc
+        adc #5
+    :
+    ; divide by 16
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    sta temp_x
+
+    lda player_pos_y
+    ; divide by 16
+    sec
+    sbc #8
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    tay
+
+    lda #16
+    jsr mul_y
+    adc temp_x
+    tax
+    lda level, X
+    cmp #0
+    beq :+
+        iny
+        tya
+        asl
+        asl
+        asl
+        asl
+        clc
+        adc #8
+        cmp player_pos_y
+        bcc :+
+        sta player_pos_y
+        lda #0
+        sta player_vel_y
+    :
+
+    ldx var_n
+    inx
+    stx var_n
+    cpx #1
+    beq @begin_check
+
+    rts
+
+right_collision_check:
+    lda #0
+    sta var_n
+    @begin_check:
+    lda player_pos_x
+    ; divide by 16
+    clc
+    adc #8
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    sta temp_x
+
+    lda player_pos_y
+    ldx var_n
+    cpx #0
+    bne :+
+        sec
+        sbc #7
+        jmp :++
+    :
+        clc
+        adc #6
+    :
+    ; divide by 16
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    tay
+
+    lda #16
+    jsr mul_y
+    adc temp_x
+    tax
+    lda level, X
+    cmp #0
+    beq :+
+        lda temp_x
+        asl
+        asl
+        asl
+        asl
+        sec
+        sbc #8
+        cmp player_pos_x
+        bcs :+
+        sta player_pos_x
+        lda #0
+        sta player_vel_x
+    :
+
+    ldx var_n
+    inx
+    stx var_n
+    cpx #1
+    beq @begin_check
+
+    rts
+
+left_collision_check:
+    lda #0
+    sta var_n
+    @begin_check:
+    lda player_pos_x
+    ; divide by 16
+    sec
+    sbc #8
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    sta temp_x
+
+    lda player_pos_y
+    ldx var_n
+    cpx #0
+    bne :+
+        sec
+        sbc #7
+        jmp :++
+    :
+        clc
+        adc #6
+    :
+    ; divide by 16
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    clc
+    ror
+    tay
+
+    lda #16
+    jsr mul_y
+    adc temp_x
+    tax
+    lda level, X
+    cmp #0
+    beq :+
+        lda temp_x
+        clc
+        adc #1
+        asl
+        asl
+        asl
+        asl
+        clc
+        adc #8
+        cmp player_pos_x
+        bcc :+
+        sta player_pos_x
+        lda #0
+        sta player_vel_x
+    :
+
+    ldx var_n
+    inx
+    stx var_n
+    cpx #1
+    beq @begin_check
+
+    rts