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Space Gun

764 bytes removed, 13:21, 4 December 2013
/* Plus Features */
The playfield also use some raster which are quite similar to the Arcade... but sadly this simply displays even more the unmasked tiles/characters from the sprites. could have been better provided the sprites were properly 4bpp coded as the "raster ink" would be used as a "sort of a mask".
== Use of Plus Features ==
*'''HardSprites :''' Plus palette is used for the title page throughout (golden/yellow logocolour fading, to get easier extra colours and ink cyclingthroughout) and * Plus raster line interrupts are used (for the visor and bullets, also changing modes for the Scanner/Radar at bottom of example)* Plus screen HUDsplit is used... those visor and scanner use some ink rotation/cycles. The Visor uses 2 Hardsprites with some colour cycles and those sprites may change if you change the selected weapon (new content * Plus hardware scrolling is loaded into the ASIC's sprite inner RAM), bullets use 2 HardSprites slots per frames (6 frames, so 12 slots) and Radar uses 2 Sprites with colour cycles toonot used. Those sprites are all magnified into pseudo Mode0 sized pixels (X=4 and Y=1). To use Harsprite for the visor * Plus DMA sound is and easy way to get this one masked and with smooth movement while the game is non masked and attribute movement basednot used.
*'''HardScrolling :''' not confirmedPlus hardware sprites are used. Being a character based graphic engine(used for the title page logo, it is quite probable that your aiming reticule, bullets, and the exact ZX Spectrum routines were usedScanner/Radar at bottom of screen HUD).
*'''Palette :''' this game clearly The hardware sprites use ink cycling. The Visor uses colours unavailable 2 sprites with some colour cycling and those sprites may change if you change the selected weapon , bullets use 2 sprites slots per frames (6 frames, so 12 slots) and Radar uses 2 Sprites with colour cycles too. Those sprites are all magnified into pseudo Mode0 sized pixels (X=4 and Y=1). To use sprite for the aiming reticule is an easy way to old Amstrad CPC paletteget masked and smooth movement while the game is non masked and attribute movement based.
*'''DMA sound channels Others :''' the sounds are minimalist... the game even do not features the Spectrum128/Atari ST chiptune (which is quite good) so it is most probable the DMA channel weren't used. *'''Raster interrupts :''' one Bitmap ink on the Mode0 part of the screen is used to display some raster effects, actually even betterly done as on the 16bit Atari ST/Amiga versions, and closer to the Arcade version. Sadly, as said before, this just displays even more the non-masked attributes from the sprites (with a lot of diagonal designs...). When not "Software attribute based sprites" are displayed, the games manages to look quite good.
*'''Mode change :''' the texts during Menu page or cinematics, and the upper HUD (top of the screen) are in Mode2 (1bpp) while the rest is in mode0 (4bpp). Despite being Mode2, the letters (characters) used 16 pixels and could have been done in mode1. This part seem to slightly bug on emulator.
 
*'''Others :'''
**multiloadings are used as the game must be quite heavy on memory requirements. on cartridge, this game properly done would have needed 256K or even 512K ROM cartridge. As a result only the 6128 config can play this (with no ROM).
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