[[File:Graphical projection comparison.png|right|320px|thumb|Projections, courtesy from wikipedia]]
[[File:3diso.jpg|ightright|320px|thumb|samples courtesy from www.olivierleborgne.com games :Head Over Heels, Batman, Super Hero, Sweevo’s World and Hydrofool.]]
''This page is intended to complete the Category:Isometric 3D, check the categories at the bottom of this page to get more related links.''
[[Pac-Mania]] for example is not really "isometric" but actually "Oblique".
Yet the term Isometric is the most commonly used, as it suit for most of those pseudo 3D -looking games, so we'll use it as a whole, despite sometimes unproperlyun-properly.
==Inaccuracy on with old school Computers==
The isometric and most parallel projection originate from engineering, Architecture, design and technical drawing.
====Asymmetric :====
X and Z axis form different angles with Y axis.
====Symmetric :====
X and Z axis form an equal angle with Y axis
*4x1 is better for vertically limited display.
==Masked Sprites and Elements==
A proper isometric render always need to get masked sprites so they may appear upon the backgroundor behind other elements.
Also some Scenery Elements which are to be put in front of sprites also have to be masked.
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 Mode1As such, the limited set of inks (only 4 ink) need a proper colour management"3D" parallel projection engine can be quite difficult to get running smoothly and fast as a lot of work may be needed for the Z80 CPU.
The following was certainly the best one, it is probably 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.==Amstrad Plus==
'''Hero Quest''' per example is quite similarConcerning the [[Plus| Amstrad Plus]] range, the extra features may be difficult to use in such an environment.
The floor-tiles and background walls are masked, the "4th colour" (grey, actually ink0) is nearly never used except for the "empty floor" or the "Mouse cursor"...
A clever use of the transparency/mask ink on the Floor/Wall tiles could enable to display this background grey on those floor/wall tiles but it wasn't done... which is a serious graphical limitation alongside a poor colours choice.
It is also to notice that the basic floor tiles use only 2 inks (Blue and dark blue) the "light cyan" seen in the jointed floor-tiles being sometimes obtained with the pixels-crossing of pixels from 2 tiles different.*'''Hardware sprites :'''
Due to them being always above the normal bitmap screen. They still can be easily used to add extra visual effects or extra HUD elements, or even to patch some foreground only elements/tiles.
Many Speccy Ports in "Proper isometric Mode1" actually still use 1bpp coded graphicscan be hard to mix with Hardsprites, but cavalier perspective games may be easier with those.
* Some remains in Monocolour display as lazy ports, be it only in gamefield In turn based GUI like games (HUD often display other colours anywaylike Hero Quest)the sprites are obviously a clever way to get a proper "Mouse cursor" with additional extra colours and ready to use mask.
*'''Examples Raster Interrupts :'''
Alien highway / Highway Encounter The diagonal graphics are not easy to mix with horizontal rasters interrupts or video Mode changes...
HBut it can still be used for some HUD or windows which may not cross the play field (with a vertical 256 pixels sized screen).A.T.E
PacManiaOr in Mode0 games : with a "lot" of existing inks, so more margin to play with those ink changes with no clashes.
The Great Escape*'''Hardwired scrolling :'''
Attack Of The Killer Tomatoeslet's say this can also be used to ease horizontal scrolling provided the kind of game actually need it.
Gauntlet III*'''Palette :''' the awesome Plus palette is always a sweet feature to use.
Molecule Man (also a bad game...)
*Other The few real Plus games manage to get the elements (background and sprites) in different colours : yet still mono-coloured themselves. this greatly increase the games quality and understandability don't make a great use of the environment despite being still inferior to real 2bpp graphics in 3 or 4 colours for Sprites or backgroundsparallel projection.
'''Examples would be :'''
Bobby bearing[[World Of Sports ( Cartridge )]] for its BMX part (cavalier perspective).
Bomb Scare Crystal Castles Fire Trap[[Operation Thunderbolt ( Cartridge )]] perhaps use some cosmetic cavalier perspective for the horizontal scrolling parts but it is more a CPC old game with "refreshed" graphics.
==Shadows==
Getting the sprites some Sprites a shadow on the floor is a nice way to ease the player's comprehension of the 3D effect and environment, yet it was rarely used.
Head over Heels is notable because when your Sprite (mostly "Head" who could glide in the air) was in "altitude" you may not easily see were it is actually in the X,Z plane.
**Hydrofool : as you float in an Aquatic environment, the game would be unplayable without this shadow (just look at the picture, yellow shadow...) to see your coordinates in the X/Z plane and judge at which height you are swimming.
==Video Modes==
The square pixels from Mode1 was usually preferred for real Isometric.
Yet games in mode 0 managed well with it or other parallel projections type too.
Some reasons the Mode1 was anyway quite popular :
*Many isometric games were Speccy Ports.
*the fine square pixels in mode1 also enable to get fine detailed sprites, while the blockier Mode0 would need those sprites to be bigger in order to manage a proper level of details.
===Mode1 :===
In Mode1, the limited set of inks (only 4 ink) need a proper colour management.
The technique used in '''Head Over Heels''' was certainly the best one :
***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".
***The doors actually manage to fit well in the background.
***Sprites and Scenery elements (objects, doors, platforms...) : they use only 3 colours and the 4th ink (ink number0) is used to get the transparency mask.
'''Hero Quest''' is quite similar yet fail to achieve this level of goodness.
The floor-tiles and background walls are masked, the "4th colour" (grey, actually ink0) is nearly never used inside those except for the "empty floor" or the "Mouse cursor"...
[[File:Heroquest possible colour variation.png|frame|none|What was, what could, what should.]]
A more clever use of the transparency/mask ink with the Floor/Wall tiles could enable to display this '''background grey''' in those floor/wall tiles but it wasn't done... which is a serious graphical limitation alongside a poor colours choice, which leads to the sprites and scenery being quite blurred into a blue messy hell as the background can't differentiate properly through the use of an additional different colour.
It is also to notice that some basic floor tiles use only 2 inks+transparency (Blue and dark blue) the "light cyan" seen in the jointed floor-tiles being then obtained by the pixels-crossing from 2 different Floor-tiles.
Many [[Speccy Port|Speccy Ports]] in "isometric Mode1" actually still use 1bpp coded graphics.
* Some remains in Mono-colour display as lazy ports, be it only in game's playfield (HUD often display other colours anyway).
'''Examples :'''
**[[Alien Highway]]
**[[Highway Encounter]]
**[[H.A.T.E Hostile All Terrain Encounter]]
**[[Pac-Mania]]
**The Great Escape
**Attack Of The Killer Tomatoes
**Gauntlet III
**Molecule Man (also a bad game...)
*Other games manage to get the elements (background and sprites) in different colours : yet still mono-coloured themselves.
This greatly increase the games quality and understandability of the environment despite being still inferior to real 2bpp graphics in 3 or 4 colours for Sprites or backgrounds, and this still enable some Amstrad CPC's specificity over the ZX spectrum : the lack of colour clashes that goes so well with Isometric variations.
'''Examples :'''
**Bomb Scare
**Crystal Castles
**Fire Trap
**Bobby bearing : yet in this one, the sprites seem to be 2bpp coded as they actually use 2 colours+transparency (White+black for sprites, darkBlue and light Cyan for scenery) or there is still a 1bpp mask over a 1bpp sprite data, then colour are chosen when displayed. This makes the sprites even more apparent over the background despite still having a 1bpp flavour.
There a comparison with the different way to do it :
[[File:Iso mode1 comparison.png|frame|none|Gauntlet3, FireTrap, HeroQuest, Head Over Heels. Notice that Gauntlet's HUD is in proper 2bpp graphics to add insult to injury.]]
===Mode0 :===
Due to the larger set of ink, there is no problem to find one ink to get the mask.
Most/All Mode0 isometric games have properly coded graphics (4bpp).
By the way because of the wider pixels, you need bigger sprites to get some details with them, so those games are quite heavy to manage and often quite slow, but delightfull to the eyes...
==Level design==
==Video modes==
The square pixels from Mode1 was usually preferred for real Isometric.==HUD==
Yet games in mode 0 managed well A problem with it or other parallel projections type tooIsometric 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 oblique HUD often cross the games windows.
Some reasons the Mode1 was anyway quite popular :
*Many isometric games were Speccy PortsThis is of course not a problem in Mode0 as the 16 colours on screen are enough to get a coloured feeling.
*And by the fine square pixels in mode1 also enable to get fine detailed sprites, while way the blockier Mode0 would need those sprites to be bigger in order to manage heaviness of a proper level Mode1 Isometric engine simply can't bother to have extra colours with the sacrifice of detailsprecious CPU resources.
==HUD==Head over Heels and many Mode1 games deal well with this lack of colours with many palette changes from room to room. While the game only display 4 colours at a time on screen, those colours change often when you explore the levels
a problem with Isometric was the need to put HUD in corners of the screen.==Scrolling==
As a result, it was rarely possible to add extra colours thanks to raster interrupts because *Few Isometric games actually included proper multi-scrolling as an Isometric engine is already quite heavy for the HUD often cross the games windows (horizontally)system.
==Scrollings==A proper scrolled isometric game would need 2 diagonal scrollings and perhaps a vertical scrolling too, not the easiest to get.
Few Isometric games actually included scrollings as an Isometric engine is quite heavy for the systemshooters were often exceptions.
H.A proper scrolled isometric game would need 2 diagonal scrollings and perhaps a vertical scrolling too.T.E / Alien highway / Highway Encounter.
Not the easiest to get.
*Cavalier perspective games were more prone to get scrolling because only a "normal" horizontal scrolling mau be needed.
Yet Some "Beat'hem All" games in approximate Cavalier Perspective managed to get some decent scrolling, often an horizontal one... Double Dragon series are typical examples of such games, with Horizontal scrolling. [[Pac-Mania]] is a notable example of multi-scrolled parallel projection game, . its Oblique projection Cavalier Perspective being perhaps more suitable for scrollings multi-scrolling as it need only 1 diagonal scrolling and 1 horizontal scrolling. '''Scrolling was often a severe lack in many Amstrad CPC's games anyway.'''
==Control and Gameplay==
A Projection based environment can be used as 2D or 3D environment/engine.
Parallel projection is quite suitable for many kind of games.
*'''Beat'hem All :''' a clever way to get good looking backgrounds.
*'''Shooters :''' diagonal shooters were quite popular yet despite being more difficult to play than Horizontal or vertical ones, they have a special graphical flavour.
*'''Platformers :''' they more rely on exploration than manic reflexes.
*'''Strategic games or RPG :''' parallel projection is perfect for good looking turn based games, the turn based element being also a good point as such engine may be quite heavy for a realtime action game.
A Projection based environment can be used as 2D or 3D environment/engine.
*'''Horizontal Oblique Cavalier Perspective :'''
Because it still have some traditional Horizontal and vertical axis, this projection often stick to the up/down and left/right way to move the Player's sprite. as As a result, this projection if more than often only cosmetic : the background looks like 3D but the game and the sprites are clearly 2D.
**'''2D :''' As in most Beat'hem'all like Renegade. Or even some shooters like MagMax. They are indeed 2D games. The vertical axis being only limited to jumps on the X axis (left/right) if available.
The problem often happens in action 2D games and in many 8-directional games (square grid).
****Examples are many Football game (view from above) where running in diagonal often enable to actually run faster than in Horizontal/Vertical on-screen directions (provided the game doesn't lag due to real time multiscrolling issues).
****Also strategic/tactical turn based games using "square grid" instead of hexagonal grid... if possible, using the diagonals of the squares is often advantageous movement wise...
**'''2D :'''Gauntlet 3 is some precursor of Diablo-like games.
The backgrounds Scenery elements are in "3D" (isometric oriented) and but you can't use the Y (3D vertical) axis(no jump), therefore you can move on the horizontal plane (X/Z) in 8 directions.
This leads to a strange and odd sensation as the levels are designed in "diagonals" on screen but the player would instinctively move mostly in up/down/left/right 2D fashion (X+Z axis at the same time).
==List of Amstrad "Isometric" and "Oblique" games :==
you can visit CPCpowers to get a list thanks to the "3d iso" keyword.
**Batman
**[[Head Over Heels]]
**[[Alien Highway]]
**[[H.A.T.EHostile All Terrain Encounter]]
**[[Hero Quest]]
**Marble Madness
**[[Revolution]]
*'''Mode0 :'''
**[[Bactron]]
**Crafton & Xunk (Get Dexter)
**Desqpotik Design
[[File:Mode0 iso games1.png|thumb|960px|none| A panel of different sort of Mode0 isometric games.]]
===='''135x135x90'''====
===='''Flattened Dimetric examples :'''====
(an even more flattened isometric, diagonal ratio for the X/Z plane is 4x1)
**Zaxx
**[[Black Land]]
===various symmetric=Various Symmetric====
Those can tend to look messy, especially in Mode0.
**Binky : ratio = X12xY4 (mode0 : X=2+2+1+1pixels, Y = 4)
===ASYMMETRIC===
===='''Horizontal Oblique examples Cavalier perspective :'''====
(X Axis is horizontal on the screen, Y axis is vertical on the screen, Z axis is oblique/diagonal on the screen)
*'''Mode1 :'''
**PacMania[[Pac-Mania]]
**Dragon's Lair
**[[Paperboy]]
[[File:Cavalier perspective mode0.png|thumb|1024px|none| A panel of different sort of Mode0 cavalier perspective games.]] ===='''Various Oblique /Trimetric examples :'''====
(X and Z axis are both oblique but with different angle = asymmetric...)
**Crystal Castles (Diamond Plateaus In Space).
==Pixel Artrenewal and Isometric==
Isometric is often used in classic Pixel Art and is emblematic of it as it was the best way to display good looking pseudo 3D FX on old computer 2D systems.
(in opposition to the modern full-real-3D).
Hence, PixelArt and This is quite due to the fact that Isometric are often /Parallel projection was made obsolete by full Real 3D computers evolution, so became synonymous nowadays with the younger ignorant generations.of Old-School Computers and Games
Hence, "PixelArt" and "Isometric graphics" are often merged nowadays in the younger ignorant generations' mind. ==Modern day isometricuses of Isometric Graphics==
Isometric 3D is still used in modern day, mostly to get an old-styled "Pixel Art" flavour.
*'''Baldur's Gate''' (and some spin-offs like Planescape Torment) featured perhaps the last great 2D engine ever produced for a Commercial super-production game : the '''Infinity Engine'''.
==Links==*'''Diablo series''' is also a well known isometric gameplay, reprising Gountlet3 in many way, but adding modern computer power and far more RPG mechanics.
'''Wikipedia's''' articles : [http://en.wikipedia.org/wiki/Graphical_projection| Graphical projection] [http://en.wikipedia.org/wiki/Parallel_projection| Parallel projection] [http://en.wikipedia.org/wiki/Isometric_projection| Isometric projection]==Links==
===Wikipedia articles===
* [http://en.wikipedia.org/wiki/Graphical_projection Graphical projection]
* [http://en.wikipedia.org/wiki/Parallel_projection Parallel projection]
* [http://en.wikipedia.org/wiki/Isometric_projection Isometric projection]
[https://www.cpc-power.com/index.php?page=database&lemot=3D%20iso List of isometric games on CPC-POWER]
[[Category:Isometric 3D| *]][[Category:3D]][[Category:Stub]][[Category:Graphic]]