diff options
| -rw-r--r-- | bunny.gbasm | 6 | ||||
| -rw-r--r-- | map.gbasm | 226 |
2 files changed, 173 insertions, 59 deletions
diff --git a/bunny.gbasm b/bunny.gbasm index 2be262c..467f9dd 100644 --- a/bunny.gbasm +++ b/bunny.gbasm @@ -90,6 +90,7 @@ Move_Bunny: LD A, $mem_viewport_x ADD B LD $mem_viewport_x, A + CALL =Load_Column Move_Bunny.horizontal_tile_move.move_viewport_end: LD A, $mem_bunny_x ADD B @@ -102,6 +103,7 @@ Move_Bunny: LD A, $mem_viewport_y ADD B LD $mem_viewport_y, A + CALL =Load_Row Move_Bunny.vertical_tile_move.move_viewport_end: LD A, $mem_bunny_y ADD B @@ -111,11 +113,11 @@ Move_Bunny: RET Display_Bunny: ; X position in $81, Y position in $80 - LD A, $mem_viewport_x + LD A, $mem_bunny_x LD HL, $9840 CALL =Print_8bit - LD A, $mem_viewport_y + LD A, $mem_bunny_y LD HL, $9860 CALL =Print_8bit @@ -1,74 +1,186 @@ Load_Map: - LD DE, $9800 + LD C, $fd + LD B, $fd + Load_Map.For_Y: + Load_Map.For_X: + LD A, C + CALL =Load_Block + + INC C + LD A, C + CP $0d + JR NZ, =Load_Map.For_X + + INC B + LD A, B + CP $0d + JR NZ, =Load_Map.For_Y - Load_Map.loop: - LD C, E + RET + +Load_Row: ; (+1/-1 direction in B) + PUSH AF + PUSH BC + PUSH DE + LD A, B + CP $01 + JR NZ, =Load_Row.Up + + LD A, $mem_viewport_y + ADD $0C + LD B, A + JR =Load_Row.Set_X_Limits + + Load_Row.Up: + LD A, $mem_viewport_y + SUB $02 + LD B, A + + Load_Row.Set_X_Limits: + LD A, $mem_viewport_x + SUB $03 + LD D, A + LD A, $mem_viewport_x + ADD $0D + LD E, A + Load_Row.For_X: LD A, D - AND 0x03 - LD B, A - PUSH BC - - SRA B - RR C - SRA B - RR C - SRA C - SRA C - SRA C - SRA C - LD A, C - - POP BC - LD B, A - LD A, C - SRA A - AND $0f - - CALL =Is_Solid - CP $00 - JR Z, =Load_Map.loop.next + CALL =Load_Block + INC D + LD A, D + CP E + JR NZ, =Load_Row.For_X + + POP DE + POP BC + POP AF + RET + +Load_Column: ; (+1/-1 direction in B) + PUSH AF + PUSH BC + PUSH DE + LD A, B + CP $01 + JR NZ, =Load_Column.Left + + LD A, $mem_viewport_x + ADD $0C + LD D, A + JR =Load_Column.Set_Y_Limits + + Load_Column.Left: + LD A, $mem_viewport_x + SUB $02 + LD D, A + + Load_Column.Set_Y_Limits: + LD A, $mem_viewport_y + SUB $03 + LD B, A + LD A, $mem_viewport_y + ADD $0D + LD E, A + Load_Column.For_Y: + LD A, D + CALL =Load_Block + + INC B + LD A, B + CP E + JR NZ, =Load_Column.For_Y + + POP DE + POP BC + POP AF + RET + +Load_Block: ; X in A, Y in B (X and B being AND with 0x0f) + PUSH BC + PUSH AF + PUSH DE + + ; Construct Tile Map address from A and B in DE + PUSH AF + PUSH BC + + AND $0f + LD C, A + LD A, B + AND $0f + LD B, A + LD A, C + + LD D, $00 + LD E, $00 + LD E, B + SWAP E + SLA E + RL D + SLA E + RL D + SLA A + OR E + LD E, A + LD A, D + OR $98 + LD D, A + POP BC + POP AF + + CALL =Is_Solid + + CP $00 + JR Z, =Load_Block.Empty + Load_Block.Solid: + LD A, $20 + LD (DE), A LD A, E - AND $20 - SRL A - SRL A - SRL A - SRL A - LD C, A - LD A, E - AND $01 - OR C OR $20 + LD E, A + LD A, $22 + LD (DE), A + INC E + LD A, $23 + LD (DE), A + LD A, E + AND $DF + LD E, A + LD A, $21 + LD (DE), A + + JR =Load_Block.End + Load_Block.Empty: + LD A, $00 + LD (DE), A + LD A, E + OR $20 + LD E, A + LD A, $00 + LD (DE), A + INC E + LD A, $00 + LD (DE), A + LD A, E + AND $DF + LD E, A + LD A, $00 LD (DE), A - Load_Map.loop.next: - - INC DE - LD A, $9c - CP D - JR NZ =Load_Map.loop - - LD DE, $9853 - LD A, $24 - LD (DE), A - LD DE, $9854 - LD A, $25 - LD (DE), A - LD DE, $9873 - LD A, $26 - LD (DE), A - LD DE, $9874 - LD A, $27 - LD (DE), A + Load_Block.End: + POP DE + POP AF + POP BC RET Is_Solid: ; X in A, Y in B, Result A PUSH BC PUSH DE - - CP $10 + + CP $15 JR NC, =Is_Solid.Not_Empty CP $02 @@ -76,7 +188,7 @@ Is_Solid: ; X in A, Y in B, Result A LD A, B - CP $10 + CP $05 JR NC, =Is_Solid.Not_Empty CP $02 |