Routines
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50396: Colour Inventory Items
Used by the routine at StartGame.
Sets the attributes of the items in the inventory tube. Each item is a block of two by two attributes. Items 1 to 4 flash in the colours of items 5 to 8 when the player is within five cells of the monster that they belong to.
Colour each place in the inventory tube.
ColourInventoryItems 50396 LD BC,50479 Point at the table of colours, and at the lowest item at 23234 (in the attribute buffer).
50399 LD HL,23234
50402 EXX Switch to the shadow registers, point at the inventory and set a counter for the eleven places in it.
50403 LD DE,48131
50406 LD B,11
ColourInventoryItems_Loop 50408 LD A,(DE) Fetch the item, and return if there are no more items.
50409 AND A
50410 RET Z
50411 CP 5 Jump to ColourInventoryItems_Monster if the item is one of the four that belong to monsters.
50413 JR C,ColourInventoryItems_Monster
ColourInventoryItems_Colour 50415 EXX Look up the colour of the item in the table of colours.
50416 EX DE,HL
50417 LD L,A
50418 LD H,0
50420 ADD HL,BC
50421 LD A,(HL)
50422 EX DE,HL
50423 LD (HL),A Colour the top two attributes of the item.
50424 INC HL
50425 LD (HL),A
50426 LD DE,65503 Move to the row of attributes above.
50429 ADD HL,DE
50430 LD (HL),A Colour the bottom two attributes of the item.
50431 INC HL
50432 LD (HL),A
50433 ADD HL,DE Move up one more row, to the next item.
50434 EXX Swap back to the main registers.
50435 INC DE Move on to the next place in the inventory, and loop back until all eleven have been coloured.
50436 DJNZ ColourInventoryItems_Loop
50438 RET Return.
Items 1 to 4 belong to the monsters. Find out whether the monster is near the player.
ColourInventoryItems_Monster 50439 PUSH AF Keep the item and the pointer to the inventory.
50440 PUSH DE
50441 CPL Turn the number of the item into the number of the monster, from 3 to 0.
50442 ADD A,5
50444 ADD A,A Multiply it by sixteen, to get the distance to the object of the monster.
50445 ADD A,A
50446 ADD A,A
50447 ADD A,A
50448 LD E,A Put the distance in DE.
50449 LD D,0
50451 LD IX,48478 Start with the first monster.
50455 ADD IX,DE Add the distance, to point at the right monster.
50457 LD C,5 Set the distance to 5 cells.
50459 CALL CheckPlayerClose Check whether the monster is close to the player.
50462 JR C,ColourInventoryItems_Flash Jump to ColourInventoryItems_Flash to make the item flash if the player is within five cells of the monster.
50464 POP DE Get the item and the pointer to the inventory back.
50465 POP AF
50466 JR ColourInventoryItems_Colour Jump to ColourInventoryItems_Colour to give the item its usual colour.
ColourInventoryItems_Flash 50468 POP DE Get the item and the pointer to the inventory back.
50469 POP AF
50470 LD A,(48050) Use the lowest two bits of the frame counter, plus five, as the colour of the item, so that it flashes.
50473 AND 3
50475 ADD A,5
50477 JR ColourInventoryItems_Colour Jump to ColourInventoryItems_Colour to colour the item.
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