ypoissant

The Photon Mapping algorithm takes the color of the surface from which it bounces into account. Not only the hue of the color but also its value and saturation. You further can control how much each object absorbs or bounces photons with the Radiance attribute and you can control how many maximum times you want your photons to bounce.

My current system is brand new. ASUS motherboard P-IV 2.6mHg processor, 512meg Kingston RAM and ATI AIW Radeon graphic card (Which shows its age and seriously need to be replaced). Softwarewise, Win XP Pro and I didn't limit applications installation either except for Visual Studio. I decided that there would be no software development of any kind installed on this computer. My previous system was a Dell-PIII 800mHz, 256meg 3 year old with the original Win98SE. The graphics card was replaced by a GeForce-II. And a ton of software of all kind. Even though it became really unstable with time, I didn't have more stability issues with A:M than with any other applications. Actually, Corel and Macromedia products where way more unstable on this computer. And Visual Studio was the application which crashed my computer the most often (but that is to be expected when you think about it). Sorry, I can't be of more help there.

I've had A:M v10.5 open non-stop, either editing or rendering or idle, for about a full week without any kind of problems. Even with Photoshop, Outlook express and other utilities opened at the same time. There are no light lists in this scene.

Arthur - I also noticed the darkness of the framed pictures as well as their cutout. It is probably due to the interaction between the photons and the attribute of the glass (refraction index and color) I will have to adjust those attributes. Setting the glass color to black there might not be such a good idea in this particular instance. The shifted reflection is simply the result of modeling a sliding frame window. Yes, Tony also suggested to add some objects under the bed. I will see what I can do with that. I also forgot to mention that the bed, the chair, the windows, the door frame and the moldings wood textures are procedurals but the door itself and the floor are maps. The wallpaper is aslo procedural. I don't know where the turtle come from. Tony?

Here is another image rendered last night. Let's call it Image 4. I've edited the list of image caracteristics 2 post up to add a description of this image. This is not rendered with Photon Mapping. I upped the environment lights intensity so that the bed and the chair does not look so dark but the walls are now washed out. BTW, I also plan to do at least 3 more photon renders: 1) with the table lamps ON and the ceiling light OFF. 2) with the night lamp ON and the ceiling light OFF. There is a night lamp between the bed and the table desk 3) with the closet door open, the closet light ON and the ceiling light OFF. All lights are bulb lights and all images are rendered in v10.5.

Image 1 1200 x 676 pixels multipass at 16 passes 5 lights arranged as a 5 point candelier located at the center of the ceiling about 1 foot from the ceiling. Intensity set at 50% and the falloff set so that it does not touch any object in the scene. Color lightly yellow. Shadow ON ray-traced with only 1 ray and shadow darkness set to 100% Radiosity ON, 1 000 000 photons, 15 bounces, sampling area: 1600 and 500 photon samples, Final gathering ON with 500 samples and 50% jitter Precompute irradiance ON All surfaces have ambiance set to 0 and radiance set to 100% (although it would be more realistic to set radiance to something around 95%) Render time: 31h Image 2 600 x 338 pixels No multipass, it uses the default antialiasing The same 5 lights candelier as for image 1 except intensity set to 100% Radiosity OFF Same surface attributes as for Image 1 Render time: I didn't note Image 3 1200 x 676 pixels No multipass, it uses the default antialiasing The same 5 lights candelier as for image 1. Intensity set to 50% 15 additional orange lights, 7% intensity and 1500cm falloff so that there is no light intensity attenuation for the entire space of the room. The lights are arranged as follow: 4 lights in the room corners near the ceiling 4 lights at the center of each wall near the ceiling 4 lights in the room corners near the floor 3 lights at the center of each wall near the floor (I didn't put a light behind the bed) [*]Radiosity OFF [*]Same surface attributes as for Image 1 [*]Render time: 1h15m Image 4 1200 x 676 pixels Multipass set to 16 passes The same 5 lights candelier as for image 1. Intensity set to 50% 15 additional orange lights, 8% intensity and 1500cm falloff so that there is no light intensity attenuation for the entire space of the room. The lights are arranged as for image 3 Radiosity OFF Same surface attributes as for Image 1 Render time: 8h30m (This kind of put the 31h into perspective. I don't think I forgot anything

JohnArtbox - OK, I had to rerender in order to get the render time cause I didn't note it before. So for a 1200x676 antialiased, the 16 light GI faker took 1h15m. I forgot to mention that the photon mapping render setup was with multipass set to 16 too. I will launch a 16 multipass render of the faker tonight and report the render time later. And also, I plan to do a render with 10 multi-ray cast soft shadows. This should give results somewhat nearer to GI but will probably take about 10 times longer. So given those numbers, photon mapping is not that long after all. No. It is not possible to bake the photon lighting. This was something possible with the actual "radiosity" technique because it actually produced a color map of all the surfaces in the scene. But although the name "photon mapping" contains the word "map", this map is actually a 3D data structure which holds the photon locations in the scene along with their color and intensity. The closest it can get to baking the information is the "precompute irradiance" step. robcat - The reflections appear lighter because of the floor color. Currently, in order to get normal reflections, the reflective surface color needs to be black. I had the same issue with the mirror which is 100% reflective but because its color was 50% gray, the reflected image was lighter than the actual image. Until I set the mirror color to black.

I feel odd to add another me too post but I have to do it. Splendid low splines mesh. I got to learn to do that.

You are correct. The first image is the result of one ceiling light furniture which is actually 5 lights arranged as 5 point a candelier. The darker image is exactly the same lighting with no additional lights to simulate GI and the other image is with additional lights to try simulate GI somewhat. I could certainly tweak the additional lights to get a more radiosity like lighting. In particular, I courd use multi-ray soft shadows but I wouldn't be able to get the nice warm colors I get with photon mapping without tweaking from the start the color of the different surfaces. Photon mapping is a technique for producing global illumination. Radiosity is another technique. But since radiosity was the first technique ever devised to produce global illumination (actually radiosity could only compute indirect diffuse illumination), "radiosity" is now often used as a generic term to signify GI. In other words, "Radiosity" is now used to mean what the first researchers had in mind when they developped the technique, which is to accurately compute all lighting effects, including direct and indirect illumination, from fully diffuse to fully reflective light bounces, reflective and refractive caustics, participating media, subsurface scatering and more. Of course, the actual radiosity algorithm results where very far from their dreams. If you want more informations about photon mapping in A:M, please visit my Photon Mapping Tutorial page.

I thought I'd also post these renders for comparison. This one of with the ceiling light. (5 bulb lights). This one is a very early render. This one is with additional lights inside and around the room to somewhat simulate indirect illumination. There are 16 additional lights positionned close to the walls.

Thanks for the comments everyone. Jim - Yes, the shoes are a tad big. I've since resized them and added some laces. Next render. David - There is indeed a culture clash in this room. This is on purpose to add tension. There is the adult culture that can be seen primarily in the decoration (the wallpaper, the curtains, the frames) and in some tidyness. And then there is the kid's culture who tries to appropriate the space (drawings on the wall, toys on the floor) and the general untidyness. The poster is a concession from the adults. And yes, the robot is supposed to be the focus of the image. I tried my best, with composition elements (bed, bat, bus, shoes, door frame) to direct the view to it. But I don't quite know what the robot is after . MixePix - I'm not sure you want to know . It took 31 hours on a P-IV, 2.6mHz, 512 meg. The render was 1200 x 676 (I resized it in Photoshop for posting. It should be about 8 hours at the intended size of 600 x 338. I used the highest Photon mapping settings mainly because of the horizontal blinds. Without the blinds, I could probably reduce the final gathering samples from 500 to 150 which would drop the render time even further to about 2 hours. modernhorse - The inhabitant of the room is a girl. But she likes to play with the boys around and is enrolled in boys games such as baseball. But I agree, there should be more girlish props in this room. Any suggestions for props?

Here is a work in progress. This a kid room. The project is a collaboration with Tony Matias (who signs Tony on the list). I plan to use this scene as a basis for the "Interior Global Illumination using Photon Mapping" tutorial. This is not quite the latest render but close to it. Any comments are appreciated.

For 1), set your light's shadow darkness to 100%. What you see is a trick which somewhat fakes indirect illumination coming from the environment. For the rest, I don't know.

Holmes, Those models are absolutely amazing. I can feel the work involved in splining the models but I can't imagine the monk job of doing and positionning the displacement maps. Excellent work.

It seems to me that there are some more work to do with the cheek bone area. It needs to be a little bit lower and more pronounced. Try to find a 3/4 view of Naomi and tweak the cheek bone to match the photo.