Routines
Prev: 45164 Up: Map Next: 45490
45166: Draw Items
Used by the routines at RunFrame and RunGame.
Draws every item in the sorted draw list at SortedDrawList, in order. The flag in each item selects what is drawn: 1 is an entity, 2 is one of the extra records (which is first copied into the temporary entity at TemporaryEntity) and 3 is one of the 20-byte records.
For a 20-byte record, the items drawn before it that overlap it are collected into the table at 45491 and then the record is drawn with DrawBlock. An extra record is drawn with DrawEntityItem after its column, row, frame, width and height have been copied into the temporary entity.
DrawItems 45166 LD HL,44943 Take the sorted draw list.
DrawItems_Next 45169 LD A,(HL) Read the kind of the next item.
45170 AND %01111111 Keep the kind of the item.
45172 RET Z Return at the end of the list.
45173 INC HL Read the address of the record and step to the next item.
45174 LD E,(HL)
45175 INC HL
45176 LD D,(HL)
45177 INC HL
45178 PUSH DE Take that record.
45179 POP IX
45181 PUSH HL Remember the next item.
45182 DEC A Draw an entity with DrawEntityItem.
45183 JP Z,DrawEntityItem
45186 CP 2 Draw a 20-byte record at DrawItems_Record.
45188 JP Z,DrawItems_Record
DrawItems_Extra 45191 BIT 7,(IX+9) Jump to DrawItems_NextItem to skip an extra record that is not in use.
45195 JR Z,DrawItems_NextItem
45197 LD L,(IX+0) Copy the column and the row into the temporary entity.
45200 LD H,(IX+1)
45203 LD (47026),HL
45206 LD L,(IX+8) Copy fields 8 and 9 of the extra record into the screen address of the temporary entity.
45209 LD H,(IX+9)
45212 LD (47036),HL
45215 LD A,(IX+11) Fetch the frame and the width.
45218 LD B,A
45219 AND %00001111 Keep the width.
45221 LD (47034),A Store the width in the temporary entity.
45224 LD A,(IX+12) Fetch the height byte.
45227 AND %00111111 Keep the height.
45229 LD (47035),A Store the height in the temporary entity.
45232 LD A,B Move the frame down from the high nibble.
45233 RRA
45234 RRA
45235 RRA
45236 RRA
45237 AND %00001111 Keep the frame.
45239 LD (47013),A Store the frame in the temporary entity.
45242 LD IX,47012 Use the temporary entity.
45246 JP DrawEntityItem Draw it.
This entry point is used by the routine at DrawEntityItem.
DrawItems_NextItem 45249 POP HL Restore the next item.
45250 JR DrawItems_Next Take the next item.
Look back through the items drawn before this 20-byte record. The alternate C counts the ones that overlap it, and the alternate HL walks the overlap table.
DrawItems_Record 45252 EXX Switch to the alternate registers.
45253 LD C,0 Clear the overlap count.
45255 LD HL,45491 Use the overlap table.
45258 EXX Switch back.
45259 PUSH IX Keep this record aside.
45261 POP IY
45263 DEC HL Step back to this item.
45264 DEC HL
45265 DEC HL
DrawItems_Previous 45266 DEC HL Read the previous item.
45267 LD D,(HL)
45268 DEC HL
45269 LD E,(HL)
45270 DEC HL
45271 LD A,(HL)
45272 CP 255 Stop at the start of the list.
45274 JR Z,DrawItems_Collected
45276 CP 3 Skip another 20-byte record.
45278 JR Z,DrawItems_Continue
45280 PUSH DE Take the previous item.
45281 POP IX
45283 PUSH HL Remember the place in the list.
45284 DEC A Test an entity now.
45285 JR Z,DrawItems_Test
45287 LD L,(IX+0) Copy the column and the row of the extra record into the temporary entity.
45290 LD H,(IX+1)
45293 LD (47026),HL
45296 LD L,(IX+2) Copy the adjusted x coordinate into the temporary entity.
45299 LD H,(IX+3)
45302 LD (47014),HL
45305 LD L,(IX+4) Copy the adjusted y coordinate into the temporary entity.
45308 LD H,(IX+5)
45311 LD (47017),HL
45314 LD L,(IX+6) Copy the adjusted z coordinate into the temporary entity.
45317 LD H,(IX+7)
45320 LD (47020),HL
45323 LD A,(IX+11) Fetch the frame and the width.
45326 AND %00001111 Keep the width.
45328 LD (47034),A Store the width in the temporary entity.
45331 LD A,(IX+12) Fetch the height byte.
45334 AND %00111111 Keep the height.
45336 LD (47035),A Store the height in the temporary entity.
45339 LD IX,47012 Use the temporary entity.
DrawItems_Test 45343 CALL TestRecordOverlap Test this item against the record.
45346 BIT 7,(IY+10) Test whether the record still has to collect this item.
45350 RES 7,(IY+10) Mark the record as having been tested against this item.
45354 CALL NZ,CollectOverlappingItem Collect the item when it overlaps the record.
45357 POP HL Restore the place in the list.
DrawItems_Continue 45358 JR DrawItems_Previous Look at the previous item.
Patch the drawing routines with this record, then draw the block. A record whose byte 10 is 17 or 18 keeps the default details 4112.
DrawItems_Collected 45360 EXX Switch to the alternate registers.
45361 LD A,C Test the overlap count.
45362 AND A
45363 JP Z,DrawItems_NextItem Leave a record that nothing overlaps.
45366 LD (45490),A Remember how many items overlap the record.
45369 LD (50771),A Give that count to the overlapped-block routine.
45372 LD A,(23792) Fetch the drawing flags.
45375 AND %00000111 Keep the low three drawing flags.
45377 LD (50781),A Give the drawing flags to the overlapped-block routine.
45380 LD A,(IY+10) Fetch byte 10 of the record.
45383 LD (49662),A Give that byte to the block routine.
45386 LD H,A Build an instruction that loads three times that byte.
45387 LD L,62
45389 ADD A,A
45390 ADD A,A
45391 SUB H
45392 LD H,A
45393 LD (49568),HL Patch that instruction into 49568.
45396 LD A,195 Take the opcode of a jump.
45398 LD (51037),A Patch it into 51037.
45401 LD HL,51116 Take DrawBlockSection.
45404 LD (51038),HL Patch the jump so that it enters DrawBlockSection.
45407 LD DE,(23783) Fetch the view origin.
45411 LD B,(IY+0) Fetch the first two bytes of the record.
45414 LD C,(IY+1)
45417 LD HL,0 Start from zero.
45420 XOR A Subtract the view origin and add the first two bytes of the record.
45421 SBC HL,DE
45423 ADD HL,BC
45424 LD (48031),HL Store the result in the drawing variables.
45427 LD H,(IY+14) Fetch the screen position saved in the record.
45430 LD L,(IY+15)
45433 LD (48033),HL Store it in the drawing variables.
45436 LD HL,4112 Take the default record details.
45439 LD A,(IY+10) Fetch byte 10 of the record.
45442 CP 17 Keep the default details when the byte is 17.
45444 JR Z,DrawItems_Details
45446 CP 18 Keep the default details when the byte is 18.
45448 JR Z,DrawItems_Details
45450 LD H,(IY+12) Take fields 11 and 12 of the record as the details.
45453 LD L,(IY+11)
DrawItems_Details 45456 LD (23795),HL Store the details.
45459 LD A,(IY+13) Fetch byte 13 of the record.
45462 LD (23797),A Store the third detail byte.
45465 LD HL,50758 Take the overlapped-block routine.
45468 LD (50136),HL Patch DrawBlockShape so that it uses DrawOverlappedBlock.
45471 LD A,26 Take the value 26.
45473 LD (46384),A Patch it into 46384.
45476 CALL DrawBlock Draw the block.
45479 LD A,8 Take the row step 8.
45481 LD (51092),A Restore it in 51092.
45484 LD (51110),A Restore it in 51110.
45487 JP DrawItems_NextItem Take the next item.
Prev: 45164 Up: Map Next: 45490