[Bf-funboard] RFC-Multipass Rendering

[William Reynish]

Very good idea. No comments. Pure cool.




--- Douglas Bischoff <bischofftep@mac.com> wrote: >
Hello, all!
> 
> I'm starting this thread in the "funboard" side
> because I am pretty  
> sure that coding this will be well beyond my skills,
> but knowing that a  
> few features recently added to Blender seem to
> suggest that more of  
> this kind of stuff is possible I thought I'd post
> out a few thoughts  
> and see if anyone bites!
> 
> The idea is "Multipass Rendering."
> 
> A recent discussion on elYsiun.com on the subject
> revealed that there  
> is a very defined method of handling multipass
> rendering in Blender,  
> but it is very work intensive. The steps (very
> abbreviated and taken  
> from Little_Cube's mini-tutorial on elYsiun at  
> http://www.elysiun.com/forum/viewtopic.php? 
> t=18247&postdays=0&postorder=asc&start=30)
> 
> 1) Main "Beauty" Pass - "Normal" Lighting: No Emit,
> No Ambient: Save  
> environment maps for reflection pass
> 2) Diffuse Pass - "No Specular" for all Lights:
> Disable CMIR texture  
> maps: No Shadows
> 3) Specular Pass - "No Diffuse" for all lights:
> Disable CMIR texture  
> maps: No Shadows
> 4) Reflection Pass - Envmap to "CMIR": "No Specular
> No Diffuse" for all  
> lights: No Shadows
> 5) Shadow Pass - Pure white background World: "Only
> Shadow" for all  
> materials: Unified Renderer
> 
> Setting each of these parameters up manually for
> every light & every  
> material, then undoing it after each pass, is
> horribly time consuming  
> and error-prone.
> 
> There are already buttons on the render control
> panel for "Shadows" and  
> "EnvMap" and "Radiosity..." My proposal is this:
> 
> 1) Add a button next to or below the "Unified"
> renderer button called  
> "Multipass"
> 2) If Multipass is selected, the following take
> place:
> 	a) Rendering to file is required
> 	b) "Extension" button is turned on
> 	c) "Do Sequence" is disabled (once the multipass
> rendering is  
> complete, sequence effects can be done USING the
> various passes.)
> 3) A subpanel is created which contains the 5 pass
> types as toggle  
> buttons. User selects which passes they are
> interested in. At the  
> bottom of the subpanel is a separate button called
> "Create Sequence"
> 4) Pressing "Render" or "Anim" causes the scene/each
> frame to be  
> rendered in the "passes" specified in step 3. The
> files are saved with  
> a single letter "B,D,S,R,K" (K from the print world
> meaning "black" for  
> shadows, open to suggestions here... is there a
> standard out there?),  
> frame number, then the extension.
> 5) If "Create Sequence" was selected, then the
> various passes are  
> combined in the sequence editor in the following
> fashion:
> 	shadow MULTIPLY (diffuse ADD specular ADD
> refraction)
> 
> Special passes created by the user, such as Ambient
> Occlusion (AO),  
> Fresnel, and Depth (z-buffer) passes can then be
> inserted by the user  
> as desired, and of course all the various passes'
> files are in the  
> saved directory for use in other programs if
> desired.
> 
> Now, all this may sound extremely cumbersome to
> code, but since you can  
> disable all Shadows with a single button click, and
> a single button for  
> all EnvMaps... I am hoping that a knowledgeable
> coder could insert  
> similar "hooks" or "flags" into the code which would
> handle the  
> conditions the 5 above "pass" types require. (i.e.
> temporarily force  
> all lamps to "no specular" and disable CMIR texture
> maps, etc.)
> 
> As a side note, if the above is possible, then being
> able to define a  
> temporary "override" material which would be used in
> place of all  
> active materials when an option in the "Multipass"
> rendering subpane is  
> checked would enable quick use of special techniques
> like Fresnel  
> passes, AO passes, mask passes, etc.
> 
> Comments welcome,
> 
> -Bischofftep
> 
> _______________________________________________
> Bf-funboard mailing list
> Bf-funboard@blender.org
> http://www.blender.org/mailman/listinfo/bf-funboard 

Yahoo! Mail (http://dk.mail.yahoo.com) - Gratis: 6 MB lagerplads, spamfilter og virusscan