Linedef type 123, Water, Translucent, No Sides, is a type of translucent water block which does not render the side textures. It is generally used when the water block's sides will not be in view anyway, such as when the water is inside a sunken pit. Since its sides are not drawn, it requires less CPU power to render.
The block is intangible, and players hear and see a "splashing" effect when moving in and out of it. While inside the block, the scene becomes distorted, and the field of view warps into wavy lines. Also, while inside the block, players will move more slowly, and their gravity is lowered slightly. If a player remains in a water block too long without grabbing air bubbles or acquiring an Elemental Shield, a countdown will be initiated after 20 seconds, just like in the original Sonic games. If the time runs out, the player automatically drowns. Water blocks can also be used to create slime and lava, if they have the right sector effects applied to them.
Setup
The flats, floor height, and ceiling height of the FOF are determined by the flats, floor height, and ceiling height of the control sector.
The alpha value of the FOF's translucency can be changed by setting the control linedef's front side upper texture to the number symbol (#), followed by a three-digit decimal number, from 000 to 255. #000 is completely invisible, whereas #255 is completely opaque. Note that in the Software renderer, there are actually only eleven different values: #000–#011, #012–#037, #038–#063, #064–#088, #089–#114, #115–#139, #140–#165, #166–#191, #192–#216, #217–#242, #243–#255, where #000–#011 is invisible, and #243–#255 is opaque. The advantage of using the completely opaque values is the ability to properly render flats which contain transparent pixels. If no value is set in the front side upper texture, however, the default alpha value of #128 will be used.
If Flag [6] / Not Climbable is checked, the water block will always render a separate light level, which means that the light level of the control sector will only affect the water block instead of affecting the block and below it. If Flag [9] / Solid Midtexture / Effect 4 is checked, the water block will use the light level of the target sector, instead of the light level of the control sector. If Flag [10] / Repeat Midtexture / Effect 5 is checked, the flats of the water block will use the "ripple" effect.
Linedef special info
Floor height
Height of bottom of FOF
Ceiling height
Height of top of FOF
Front upper texture
Alpha value of FOF's translucency, from #000 to #255 (#000 is completely invisible, #255 is completely opaque, #128 is default)
Linedef flags
[6] Not Climbable: Always renders a separate light level [9] Solid Midtexture / Effect 4: Uses light level of target sector instead of the control sector [10] Repeat Midtexture / Effect 5: Flats use the "ripple" effect
1F31 – Without flags 21F31 – Not Climbable 80001F31 – Solid Midtexture 40001F31 – Repeat Midtexture 80021F31 – Not Climbable + Solid Midtexture 40021F31 – Not Climbable + Repeat Midtexture C0001F31 – Solid Midtexture + Repeat Midtexture C0021F31 – Not Climbable + Solid Midtexture + Repeat Midtexture
Aesthetic tips
Water blocks are generally put in a pit, to simulate real water. But since water blocks are set up like any other FOF, they can be made to float in the air, or rest on top of a flat surface without a pit. However, this is not recommended, as it looks unrealistic.
While water blocks can be used alone, it is common (and generally recommended) to apply a hue to it. This is done by creating another control sector using a colormap (or by applying it to another linedef on the water block's control sector) and tagging the water block's control sector to create the hue within the water block.
