Routines
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53252: Paint Wide Entity Attributes
Used by the routine at Process_Wall_Bouncing_Enemy.
Paints the entity colour attribute across a three-cell-wide, three-row region of the attribute area at the entity's screen position. Uses Screen_Row_Address_Lookup_Table to resolve each pixel row to its attribute address; the colour is read from shadow B'. Called by Process_Wall_Bouncing_Enemy.
Input
HL Entity state byte pointer (Y and X positions follow)
Paint_Wide_Entity_Attributes 53252 INC HL Step to the entity Y position and load the attribute colour base into D.
53253 LD D,70
53255 LD E,(HL)
53256 INC HL
53257 SLA E Shift the Y position left to form the row address table index in DE.
53259 RL D
53261 LD A,(HL) Rotate the X position right three places to derive the attribute column.
53262 RRA
53263 RRA
53264 RRA
53265 AND %00011111 Keep the attribute column index.
53267 LD C,A Store the column index in C.
53268 EXX Copy the entity colour attribute from shadow B' into B.
53269 LD A,B
53270 EXX
53271 LD B,A
Write the entity colour to three adjacent attribute cells in each of three consecutive entity rows.
53272 LD A,(DE) Look up the first attribute row address and add the column offset.
53273 ADD A,C
53274 LD L,A
53275 INC DE
53276 LD A,(DE)
53277 LD H,A
53278 INC DE
53279 LD A,H Isolate the attribute page bits.
53280 RRCA
53281 RRCA
53282 RRCA
53283 AND %00000011 Keep only the two attribute page bits.
53285 OR %01011000 Combine with the attribute area base address.
53287 LD H,A Store the computed attribute high byte.
53288 LD (HL),B Write the entity colour to three adjacent attribute cells.
53289 INC HL
53290 LD (HL),B
53291 INC HL
53292 LD (HL),B
53293 INC DE Advance the row address pointer to the second entity row.
53294 INC DE
53295 INC DE
53296 INC DE
53297 INC DE
53298 INC DE
53299 INC DE
53300 INC DE
53301 INC DE
53302 INC DE
53303 INC DE
53304 INC DE
53305 LD A,(DE) Look up the second attribute row address and add the column offset.
53306 ADD A,C
53307 LD L,A
53308 INC DE
53309 LD A,(DE)
53310 LD H,A
53311 INC DE
53312 LD A,H Isolate the attribute page bits.
53313 RRCA
53314 RRCA
53315 RRCA
53316 AND %00000011 Keep only the two attribute page bits.
53318 OR %01011000 Combine with the attribute area base address.
53320 LD H,A Store the computed attribute high byte.
53321 LD (HL),B Write the entity colour to three adjacent attribute cells.
53322 INC HL
53323 LD (HL),B
53324 INC HL
53325 LD (HL),B
53326 INC DE Advance the row address pointer to the third entity row.
53327 INC DE
53328 INC DE
53329 INC DE
53330 INC DE
53331 INC DE
53332 INC DE
53333 INC DE
53334 INC DE
53335 INC DE
53336 INC DE
53337 INC DE
53338 INC DE
53339 INC DE
53340 LD A,(DE) Look up the third attribute row address and add the column offset.
53341 ADD A,C
53342 LD L,A
53343 INC DE
53344 LD A,(DE)
53345 INC DE
53346 RRCA Isolate the attribute page bits.
53347 RRCA
53348 RRCA
53349 AND %00000011 Keep only the two attribute page bits.
53351 OR %01011000 Combine with the attribute area base address.
53353 LD H,A Store the computed attribute high byte.
53354 LD (HL),B Write the entity colour to three adjacent attribute cells.
53355 INC HL
53356 LD (HL),B
53357 INC HL
53358 LD (HL),B
53359 RET Return.
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