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diff --git a/externals/gridflow/doc/stuff.txt b/externals/gridflow/doc/stuff.txt deleted file mode 100644 index 2a495735..00000000 --- a/externals/gridflow/doc/stuff.txt +++ /dev/null @@ -1,144 +0,0 @@ -Grid Literals - In every grid-accepting inlet, a list may be sent instead; if - it consists only of integers, it will be converted to a - one-dimensional grid. Else it may contain a single "#" sign and - integers on both sides of it, where the ones to the left of it are - fed as arguments to an imaginary [#redim] object and the one to the - right of it are fed through that [#redim]. - In every grid-accepting inlet, an integer or float may also be sent; - it will be converted to a zero-dimensional grid (a scalar). - -Grid Protocol - a grid has an associated number type that defines what are the possible values for its elements - (and how much space it takes). the default is int32. - a single-dimensional grid of 3 elements (a triplet) is called dim(3). a - three-dimensional grid of 240 rows of 320 columns of triplets is called - dim(240,320,3). - There is a sequence in which elements of a Grid are stored and - transmitted. Dimension 0 is called "first" and dimension N-1 is - called "last". They are called so because if you select a - position in the first dimension of a grid, the selected part is of the same - shape minus the first dimension; so in dim(240,320,3) if you select - row 51 (or whichever valid row number), you get a dim(320,3). if you select - a subpart two more times you get to a single number. - At each such level, elements are sent/stored in their numeric order, - and are numbered using natural numbers starting at 0. This ordering usually - does not matter, but sometimes it does. Most notably, [#import], [#export] and [#redim] care about it. - On the other hand, order of dimensions usually does matter; this is - what distinguishes rows from columns and channels, for example. - Most objects care about the distinction. - A grid with only 1 element in a given dimension is different from one - lacking that dimension; it won't have the same meaning. You can use this - property to your advantage sometimes. - Zero-dimensional grids exist. They are called dim(). They can only contain - a single number. -Picture Protocol - This section is useful if you want to know what a picture is in terms of a grid. - A picture is a three-dimensional Grid: 0:rows 1:columns 2:channels - -Channels for the RGB color model are: 0:red 1:green 2:blue - Because Grids are made of 32-bit integers, a three-channel picture uses - 96 bpp (bits per pixel), and have to be downscaled to 24 bpp (or 16 bpp) - for display. That huge amount of slack is there because when you create - your own effects you often have intermediate results that need to be of - higher precision than a normal picture. Especially, results of multiplications - are big and should not overflow before you divide them back to normal; - and similarly, you can have negative values all over, as long as you take - care of them before they get to the display. - In the final conversion, high bits are just ignored. This means: black is - 0, maximum is 255, and values wrap like with % 256. If you want to - clip them, you may use [# max 0] and [# min 255] objects. - -The following are called VecOps because each operation happens between more than just two numbers. -A first kind of VecOp are those that arise when a pair of numbers (A0,A1) is considered as a single number A0+A1*sqrt(-1). -If you need complex numbers but don't know yet how they work, learn them using a math tutorial and then those VecOps will begin to seem familiar. -All the complex number operators are only for floats. -TODO: fill the last two columns of this table. - -Synchronisation - -In GridFlow you cannot send two grids in different inlets at the -same time. You have to use [#finished] together with (possibly) [fork] and [#store], -which can be cumbersome. If you don't do this, the result is undefined -behaviour (or crash!). -There are two exceptions: [#store] and # allow right-inlet grids to be buffered if an operation is occuring on left inlet. This -should make many programs simpler. - - -Introduction - - The philosophy that guides PureData is a simple but powerful one: - the software must first provide the user with generic tools - rather than imposing pre-cooked effects. In other words the user - should have total freedom. - - GridFlow follows that philosophy: it first defines elementary - mathematical operations. Those can in turn be used as simple - visual effects or be combined to produce more complex effects. - - The strategy followed by most video plugins for PureData and MAX/MSP, is - to provide the user first with constructs for manipulating video - streams at a fairly high level. The strategy put forward by GridFlow - is different. - - It can be said that in all those video plugins there are three layers: - the first, the low level, is not accessible to non-programmers (and fairly - difficult of access even to programmers); the second, mathematical, where - one needs not to be a C++ programmer, but still requires a good - understanding of how numbers and pixels and colours and geometry work; and - a third level that looks more like the software an artist would like to - use. - - In other video plugins there is a fairly low emphasis on the second - layer. In GridFlow that layer is very strong and opens many possibilities. - Even though the third layer in GridFlow is not as developed as it could, - the second layer may be used to produce third-layer object classes much - more quickly. - - GridFlow provides a unifying view of multimedia information. Several - kinds of data -- raster graphics in any number of channels, coordinate - transforms, matrices, vectors -- may all be represented by Grids - (also known as multi-dimensional arrays). Grids exist in several ways: they - are usually streamed from object to object, but they can also be stored in - memory, stored into a file, sent through the network. - - Here is an example of how things work in GridFlow. (if you want more - information, consult the rest of this manual) - - A picture is a three-dimensional Grid: - 0 : rows - 1 : columns - 2 : channels - - Pictures come in all sorts of heights and widths. The channels, however, - are more limited in number. Usually it's three: Red, Green, Blue. - - A coordinate transform, when specified pixel by pixel, may be a - three-dimensional Grid in which the two "channels" are Y and X, - representing row-and-column positions in a separate picture. - - Other shapes of grids could be designed to represent various things; - for example, configuration for blur effects. Grids could be useful for - things not directly related to raster pictures (e.g. sound recordings). - Those are all kinds of things you could actually develop _within_ the - PureData / GridFlow framework. You don't need to wait for me. - - -GridFlow Release - -dir=gridflow-0.9.6; tag=gridflow_0_9_6 -svn copy svn+ssh://gridflow.ca/home/svn/gridflow/trunk svn+ssh://gridflow.ca/home/svn/gridflow/tags/$tag/ -svn export svn+ssh://gridflow.ca/home/svn/gridflow/tags/$tag/ $dir -chmod -R go=u-w $dir && tar cfzvv $dir.tar.gz $dir && rm -rf $dir -scp $dir.tar.gz gridflow@artengine.ca:public_html/download -mv $dir.tar.gz /home/matju/GridFlow -cd doc/homepage; pico index.html; make install - -download somewhere else and try to compile -pd-announce mlist : post release - -Committed revision 4239. -Warning: 'post-commit' hook failed with error output: -/home/svn/gridflow/hooks/post-commit: line 49: /home/svn/gridflow/hooks/svn-mailer.log: Permission denied - -svn copy svn+ssh://gridflow.ca/home/svn/gridflow/tags/$tag/ https://pure-data.svn.sourceforge.net/svnroot/pure-data/trunk/externals/gridflow/ |