What does rendering to texture add?

http://www.gamasutra.com/features/19991112/pallister_pfv.htm

I've stumbled upon this short doc about some capabilities offered by rendering directly to texture. This is giving me extra inspiration, keeping in mind the usage of FastExt DLL in the userlib forum wich adds the support of this feature for Blitz3D.

The only reason why we don't have this support in Blitz3D's commandset is probably that this feature isn't compatible with all graphics hardware. But I would like to see who can`t perform a render to texture.

FastExt topic: http://www.blitzbasic.com/Community/posts.php?topic=75961

DBPro does rendering to texture fine. The whole rendering to texture can be VERY useful especially for special effects like camera displays or other effects.

Yeah, reflections, full screen effects, they add a bit extra graphics wise. No reason why you can't make a great game graphically without it though :o)

...and an absolute must for a game like Portal.

that most likely should be quite an inexistant issue.
Even Intel Onboards and cards back till TNT1 or 2 are capable of R2T ... so its at best an excuse for 2D cards that do not have TnL but on those card it does not make a difference anyway ... they will run totally crappy in graphics 3d mode.

you can use it to render gui's to textures and draw the gui on polys like in doom 3 and translate the mouse screen coords to manipulate the widgets on the texture rendered UI.

Making for some nice immersion in FPS type games.

it would be bloody handy if it was implemented.

We can already render to texture - albeit 3rd party.

I better not have to dig it out or else there will be trouble.

Call of Cthuthlu had some great 'postprocessing' fx - which I assume was the game rendering to a texture, processing the render and then displaying to screen.

The screen would warp and blur in reaction to your charcter's fear and growing madness - for example when suffering from vertigo or battling the 'deep ones'. Alot of console fanboys couldn't handle it, ('why does the screen keep blurring?!! - this sux!'), but it was a great effect.

I believe that "Tom Speed's" dx7 dlls will facilitate rendering to a texture.

on current gen cards, copyrect has the same speed as render to texture on flag 256 textures
I assume thats because they emulate fixed function pipeline through shader and the driver is intelligent enough to realize what you do and "modifies" it to be a render to texture internally.