My Gallery 4
Welcome on page four of my POV-Ray image gallery. This page deals with one of my favourite images.
The Office Coffee Corner
The Office Coffee Corner is one of my favourite pictures. It always reminds me of my days at the university: Sitting together with friends and having coffee and a piece of cake. One day in 1997 the sun shined through the blinds and create an atmospheric scenery. A second later I knew that's my next scene.
The cups are made of lathe objects, afterwards textured by image maps, except the blue cup of course. The coffee powder package, the three cream packages in the foreground, and the dry milk powder glass are csg objects, textured with scanned images.
The sun light effect at the background wall is created by placing small white stripes in front of an arealight source. The arealight is responsible for the soft shadows but also for a pretty long rendering time.
Although it is my favourite image, it is not perfect. The finish of the cups is not shiny enough and contains too much ambient light. The coffee package looks like a brick, a real package is not 100% plain and appears much softer. Ok, these are only two points but I have more...
Perfecting the Coffee Corner
As you already know I like the image but I am not completely satisfied. Therefore I decided to give it a second try, five years later. First of all, it was necessary to get the old scene file running on the latest version of POV-Ray. This was not very difficult. I had to remove the old radiosity settings and to modify the transparent textures, because version 3.5 does not longer mix interior and exterior of an object.
The next step was the redesign of the cups because the old cups were pretty squared. So I started from the scratch. Lathe and surface of revolution objects are pretty useful for creating cups, glasses, bottles and so on, but it takes some time to find the right control points. Therefore I just took the old fashioned approach and designed my new cup by using csg. A torus on top and one at the bottom, a cylinder in between, that's it. The handle is a stretched and cut in half torus. Two deformed spheres were added to the contact place of handle and cup body to make the mug more realistic.
Afterwards I started to remove the bump maps from the cap of the cream powder box and body of the purple cream packages. POV-Ray 3.5 offers scripting support for constructing object compositions by code. Therefore I built code for arranging small cylinders in a circle. This makes a much better cap and body. Bump maps are great but the pattern is just an illusion and not real (see manual, topic normal). After getting rid off the bump maps I improved all textures to stress the overall material characteristics much better.
Well, the result does not look bad, but still not perfect. Light is an important fact. The old office scene used an arealight shining through a blind to create the morning sun effect. So the new scene uses the same attempt. A lot of small, thin boxes are forming the blind. A single value in the code controls the opening angle. The image on the right shows you the result.
The image is still not what I want. I does not look like morning sun and it is pretty dark. Therefore I started to use radiosity. A global gray sphere lights up the complete scene. The radiosity settings were taken from the rad_defs.inc include file (Radiosity_Final). This gives a pretty nice overall light but it is still not sunny enough. I modified the area_light a little bit and used White*3 as color. This gives a really bright light. That's what I want!
Ok, the image looks pretty good to me and that's the right time to start to play around with it. The following images are modifications of the original one: changed blind position, changed cup color, and changed cup texture. Enjoy!
You can download the script file of the main scene here. Please pay attention, it does only contain the POV-Ray scene files and not the huge image maps for the coffee box and cream packages. I cannot offer a download to you for these file because of size and copyright limitations. Download the coffee corner script file.