Documentation Talk:Reference Section 1
Partial Output Options
|Set first column to n pixels|
||Set first column to n percent of width|
|Set first row to n pixels|
||Set first row to n percent of height|
|Set last column to n pixels|
||Set last column to n percent of width|
|Set last row to n pixels|
||Set last row to n percent of height|
When doing test rendering it is often convenient to define a small,
rectangular sub-section of the whole screen so you can quickly check out one
area of the image. The
End_Column options allow you to define
the subset area to be rendered. The default values are the full size of the
image from (1,1) which is the upper left to (w,h) on the lower right where w
and h are the
Height=n values you have set.
Note: if the number specified is greater than 1 then it is interpreted as an absolute row or column number in pixels. If it is a decimal value between 0.0 and 1.0 then it is interpreted as a percent of the total width or height of the image.
Start_Column=0.75 starts on a row 75% down from the top at a column
75% from the left. Thus it renders only the lower-right 25% of the image
regardless of the specified width and height.
+EC switches work in the same way as the corresponding INI-style
settings for both absolute settings or percentages. Early versions of POV-Ray
allowed only start and end rows to be specified with
+En so they are still
supported in addition to
When rendering a subset of *columns* (
+sc/+ec) POV-Ray generates a full width image and fills the not rendered columns with black pixels. This should not be a problem for any image reading program no matter what file
format is used.
When rendering a subset of *rows* (
+sr/+er) POV-Ray writes the full height into the image file header and only writes those lines into the
image that are rendered. This can cause problems with image reading
programs that are not checking the file while reading and just read over
If POV-Ray wrote the actual height of the partial image into the image header there would be no way to continue the trace in a later run.
- Merged correction (writed->writes) back into main document. As well as missing caps on 1st words of last two paragraphs. BTW: It's not necessary to copy the ENTIRE page just the affected section(s) please. --jholsenback 03:30, 28 May 2010 (UTC)
- Can someone check if there is still such system as MS-Dos for 3.7 ?
On MS-DOS with an eight character limit, myscene.pov would render to mysce001.tga through mysce100.tga. --Le Forgeron 22:05, 10 November 2010 (UTC)
- Adding +STP/Frame_Step with #5183 (if/when merged)
Subsets of Animation Frames
||Set subset starting frame to n|
||Set subset starting frame to n percent|
||Set subset ending frame to n|
||Set subset ending frame to n percent|
||Set the increment to the frame number, default to 1|
When creating a long animation, it may be handy to render only a portion
of the animation to see what it looks like. Suppose you have 100 frames but
only want to render frames 30 through 40. If you set
Final_Frame=40 then the clock would vary from 0.0 to 1.0 from
frames 30 through 40 rather than 0.30 through 0.40 as it should. Therefore
you should leave
to selectively render part of the scene. POV-Ray will then properly compute the
Similarly, if you only want to render a tenth of the frames, you can use
Frame_Step=10 to jump over the nine non-rendered frames between the rendered frames.
Usually you will specify the subset using the actual integer frame numbers
however an alternate form of the subset commands takes a float value in the
range 0.0 <=n.nnn <=1.0 which is interpreted as a fraction of
the whole animation. For example,
Subset_End_Frame=0.667 would render the middle 1/3rd of a
sequence regardless of the number of frames.
--Le Forgeron 22:05, 10 November 2010 (UTC)
- merci for doing the doc updates related to your improvements ... it's been done --jholsenback 11:18, 13 November 2010 (UTC)