The colladaLoader is a java import library to view Google Sketchup files (dae and kmz) inside a Processing IDE
The importer is tested with latest Sketchup release 8.0.16846 12/19/2012
(To handle it read instructions further down)
Install it as plugin with Library Manager:
Choose menubar "Sketch" → "Import Library..." → "Add Library..."
then search for "Collada Loader"
Or get latest version here as zip.
Older library versions won't work with Processing version 2.0 so they're removed from net.
Fig 1: ColladaLoader throws Java Exceptions if you don't ungroup the entire model or you try to load old kmz / dae versions.Zoom
Fig 2: Processing produces blurred graphics on the sketch if you don't apply that step. This menu item is not available if SketchUp already considers the texture to be 'unique'.In this example: Susan contains no textures but the wall does.Zoom
Considering the rules of Sketchupversion groups and textures, export the model into Processing now:
The examples folder contain a demo.pde which shows the usage of the library. The very basics to run ColladaLoader is adding the following code into Processing sketch:
size(500, 500, OPENGL);
model2 = new ColladaLoader("susan.kmz",this);
Your'e able to instantiate more than one model. ColladaLoader loads in different ways so there exist 3 reserved file suffixes for it:
Take a note that Processing zero points start not in the middle of the sketch and some translations may be nessessary before drawing.
The loading or drawing of 3D models claim lots of CPU time and RAM. That may produce several runtime problems. It can be assumed that the model has been loaded into memory correctly (consistent data) if no explicit "ColladaLoaderException" occurs. There is some ways to improve the performance:
The class cooladaLoader.ColladaLoader is the entry class and defines the interface too. Whose methods support all the features what is mentioned on the top of this doc. The required data to display the model is wrapped into two arrays which resides in this class:
The coordinate system and color range of Sketchup is converted into Processing specifications. Following a method/constructor list:
Standart constructor to load the model
The String defines a file located in the data path. Files only can end with following suffixes:
".dae" or ".kmz" = Sketchup 8 files
".dat" = serialized objects created by ColladaLoader
PApplet defines the current sketch. Colladaloader uses some of its convenient methods internally.
Instantiating more than one model is valid.
|void draw()||a convenient automatism to draw the model. Note that any model data changes at runtime is displayed immediately.|
|Getter methods to access model data|
|void shift(float, char)||
translates the model. The changes won't be reseted at runtime
the float defines the length in pixels
the char defines the 3D axis. Valid chars are: 'x', 'y', 'z'
|void rotate(float, char)||
rotates the model. The changes won't be reseted at runtime
the float defines the angle in radiant
the char defines the rotating axis. Valid chars are: 'x', 'y', 'z'
resizes the model. The changes won't be reseted at runtime
the float defines the scalefactor. 0.5f makes smaller, 2.0f makes bigger
creates a serializable object and saves the
current condition of the model at runtime to a new file in data path
String defines the filename and must end with ".dat"
Those classes wrapp all required data to display the model. Each object contains data for one entity. It correlate to coordinates and texture formates of Processing and supports read/write access. Here is a list of properies:
|Point3D A, B, C||
Vertex coordinates: Each Point3D contains 3 floats (x, y, z)
Example for r/w access: "myTriangle.A.x"
|Point2D texA, texB, texC||
Image coordinates for each vertex: Each Point2D contains 2 floats (x, y). If no texture exist for this shape the value is null
Example for r/w access: "myTriangle.texA.x"
Defines the color of this shape. It contains 4 floats: red, green, blue, transparency. If any texture exist for this shape the value is null
Example for r/w access: "myTriangle.colour.red"
|boolean containsTexture||Defines the draw handling. The value is true if any texture exist for this entity. Don't overwrite it.|
|String imageFileName||The name of the texture. Don't overwrite it|
|PImage imageReference||Is used from Processing to draw the texture. Don't overwrite it.|
|Point3D A, B||
Vertex coordinates: Each Point3D contains 3 floats: x, y, z
Example for r/w access: "myLine.A.x"
Defines the color of this shape. It contains 4 floats: red, green, blue, transparency.
Example for r/w access: "myLine.colour.red"
There exist 3 fundamental jobs for the entire architecture what must be done:
The parsing operates with the DOM model and is located in package xmlMapping. At first the XML tree is loaded into memory by Processing API. As next step it follows a readout of each xml tag. For that purpose wrappers are created whose classnames are equal to xml tag names. Whose constructors read xml data or instantiate further wrappers. The order of instantiating those wrappers is important because some wrapper objects are linked to each other. Hence, such objects already must exist or be parsed, respectively. For this controlling there exist the class ColladaRAWLoader. It's the package entry class and contains a main method to test this subpackage separately as well.
The output from ColladaRawLoader class contain data which is based on Sketchup specifications such as coordinate system or color ranges and must be converted to Processing specifications. Furthermore, the data still don't include textues but just filenames of them which files have to be loaded before, and kmz files must be unzipped first. These are jobs that the class LoadingHelper does. It's located in the parent package (cooladaloader). The interface ColladaLoader makes use of it.
The xml structure of a .dae files applies the specifications of collada.org. Whose interface definitions permit lots of combinations of xml tags so it's possible that other 3D programms (e.g. cinema4d), if they export collada likewise, define another xml tree or data. Actually, those definitions diverge from sketchup version to version too. Thats why the ColladaLoader library works on Sketchup version 8 (release dec 2012) only.
Fig 4: On the one hand, the xml tree is a static structure on the other hand there exist dependencies of data what the xml tags or child tags contain. Those two facts must be considered in order to map those data into java objects. To get the point in this case: The order in reading the tags start from bottom up.Zoom
Fig 5: This example is a detailed view of xml data what contain one triangle. Vertice coordinate or texture-points are stored here. The <p> tag is a subtag of <lines> or <triangles> and contain indices they link to an index position of a <float_array> tagZoom
In this example the Offset 1 is allocated to textures and the vertices have offset 0. After parsing we get following results:
The <lines> tag construction is simillar. An <accessor> tag says how to read a <float_array> tag.
For further details refer to javaDoc or code comments in each classes.
Last Update: June 2013