Changes
**Example : '''W*H*B''', a modern Bloxorz' Clone on ZXSpectrum.
**A More CPC oriented example game is probably '''Frontiers''' (Zafiro Software (1988)).
==Masked Sprites and Elements==
A heavy job is needed to define the masks and sprites "priority" so the 3D effect works : the background elements being obscured by the foreground elements.
*'''Mode1 :'''
In Mode1, the limited set of inks (only 4 ink) need a proper colour management.
The following was often the best one, it is the technique used in head Over heels :
***Background : can be in 4 colours, it is used for the floor, HUD and backgrounds walls only. You can use a set of 2D tiles with no mask and those can never be "foreground"
***Sprites and fore-ground elements (objects, doors, platforms...) : they use only 3 colours and the 4th ink is used to get the mask.
Heroquest per example is quite similar.
The floortiles and walls are masked, the 4th colour (grey) is nearly never used except for the "emptyfloor"... A clever use of the transparency with the Floor/Wall tiles could enable to display this grey on those but it wasn't done... which is a serious graphical limitation alongside a poor colours choice.
==Shadows==
Yet putting a vertical shadow was heavier on the CPU and Ram consuming...
==Level design==
The background elements being obscured by the foreground elements, a proper level design is needed so most crucial elements remain visible.
Yet this can also used to put hidden features and secret passages too.
==Video modes==
a problem with Isometric was the need to put HUD in corners of the screen.
As a result, it was rarely possible to add extra colours thanks to raster interrupts because the HUD often cross the games windows (horizontally).
(in opposition to the modern full-real-3D).
==Control and Gameplay==
