Bitmap Object

description

K-3D uses Bitmap objects to contain file-based or procedural bitmap images for use by a wide range of objects, including Textures, ParticleBursts, and ImageLayers, among others. Bitmap objects are also used to create new images and to perform image-processing functions on rendered frames.

creator: Shead Data Processing
version: 1.00
interface:

bitmap_ui1.gif (3445 bytes)File Path: Displays the file path to the image file, if this Bitmap is using a file for the image.

Procedure: Used to create a new Bitmap Procedure for the Bitmap image, select an existing Bitmap Procedure, or load a new image file.

Width: Displays the width of the selected image file, or controls the width of the Bitmap image if a Bitmap Procedure is selected.

Height: Displays the height of the selected image file, or controls the height of the Bitmap image if a Bitmap Procedure is selected.

View: Displays a full size preview of the selected Bitmap image.

Sequence: Enables a sequence of Bitmap images to be used.

From/To: Allows you to specify  the first and last sequential Bitmap images to be used.

Use Image Alpha: Allows the Bitmap's Alpha channel to be used.

 

 

bitmap_ui2.gif (3174 bytes)File Path: Displays the file path to the alpha channel file, if this Bitmap is using a file for its’ alpha channel.

Procedure: Used to create a new Bitmap Procedure for the Bitmap alpha channel, select an existing Bitmap Procedure, or load a new alpha channel file.

Width: Displays the width of the selected alpha channel file, or controls the width of the Bitmap image if a Bitmap Procedure is selected.

Height: Displays the height of the selected alpha channel file, or controls the height of the Bitmap image if a Bitmap Procedure is selected.

View: Displays a full size preview of the selected Bitmap image.

Sequence: Enables a sequence of bitmap images to be used.

From/To: Allows you to specify  the first and last sequential Bitmap images to be used.

 

 

 

bitmap_ui3.gif (33717 bytes)Image Preview (unlabelled): Displays a thumbnail image of the Bitmap’s RGB channels.

Alpha Preview (unlabelled): Displays a thumbnail image of the Bitmap’s Alpha channel.

Close: Closes the Bitmap interface.

Record: Opens a file dialog allowing you to save the contents of this Bitmap to disk in the image format of your choice.

restrictions: None.
use:

Create a new Bitmap object by double clicking on "Bitmap" in the Object panel, or by selecting the "--- new Bitmap ---" item in the "Bitmap" pulldown in a Texture or other object. The first thing you will see is the "Open Image File" file dialog.

If you want this Bitmap object to utilize a bitmap file already existing on your hard drive, use the file dialog to select the bitmap file now. Note that the file dialog only allows you to select files from one of the bitmap file formats supported by K-3D: Windows Bitmap (bmp), Targa Image (tga), and JPEG (jpg). You can use the "Files of Type" pulldown box to filter out individual file formats, or you can leave it set to "All Image Files" (the default). Select a bitmap image to load. The Bitmap dialog will open, displaying info about the file you just loaded. The File Path control displays the location of the image, while Width and Height display its’ dimensions. Note that these three controls are all "read-only" ... you cannot change their values because these parameters are determined by the contents of the file on disk. You can click the View button to open a BitmapViewer that displays the Bitmap image full size. When you click on the "Alpha" tab of the Bitmap dialog, you’ll see similar information displayed for the image’s alpha channel. In this case, the File Path is blank, and the Width and Height controls contain the same values as those on the "Image" tab, because by default, the Bitmap object’s alpha channels is being drawn from the same file as the image. If an image does not contain an explicit alpha channel, the Bitmap Object will provide a default, 100% opaque alpha channel. You can click the View button to open a BitmapViewer that will display the Bitmap alpha channel full size as a greyscale image. If you move to the "Preview" tab of the Bitmap dialog, you will see the image displayed as two squares: the square on the left is a thumbnail of the Bitmap image, and the square on the right is a thumbnail of its’ alpha channel.

If you wish instead to generate a custom procedural bitmap with this Bitmap object, hit the Cancel button in the file dialog that is opened when you first create the Bitmap. The Bitmap dialog will open. Note that File Path is blank, and the Width and Height controls are set to "0" for both the "Image" and "Alpha" tabs. Also note that the Width and Height controls are no longer read only: you can enter values for Width and Height to make your procedural bitmap as large or small as you like. Note that the Width and Height values are always the same for the image and alpha channels - when you change a value on one tab, the values automatically change on the other. You use the Procedure pulldown boxes on the "Image" and "Alpha" tabs to specify which algorithms should be used to control the image and alpha channels respectively. When you open either Procedure pulldown box, you will see a list of options including a series of "--- new ProcedureType ---" items, where ProcedureType is the name of a Bitmap Procedure object installed on your system. At a minimum, you should see "--- new Checkerboard ---", "--- new FractalNoise ---", and "--- new Marble ---" in the list, since these are the three Bitmap Procedure objects shipping with K-3D as of this writing. Selecting one of these items will create a new Bitmap Procedure object of the given type, and assign it to the image or alpha channel, depending on which you are working with. The pulldown box list will also contain a list of names of all the Bitmap Procedure objects that have already been created within the current document. This allows you to share a Bitmap Procedure object between two Bitmap objects, or between a Bitmap object’s Image and Alpha channels.

When you create a new Bitmap Procedure object, its’ dialog will open and you can alter its’ controls in the usual fashion to alter the image it creates. If you close the Bitmap Procedure’s dialog, you can reopen it either by double-clicking the LMB on its’ name in the Hierarchy Panel dialog or by clicking the Edit button on the appropriate channel tab. As you make changes to a Bitmap Procedure, you’ll see the Bitmap dialog "Preview" tab update automatically, along with any open BitmapViewers, and all Camera.

If you want to change the image file that a Bitmap utilizes, or you want to reload the same image file after making changes to it in another program, select the "--- new File Image / Alpha" in the Procedure pulldown box. A file dialog will open and you can select the file.

If you want to use separate files for the image and alpha channels, simply create the Bitmap object, then use the "--- new File Image ---" item in the "Image" tab Procedure pulldown or the "--- new File Alpha ---" item in the "Alpha" tab Procedure pulldown to specify separate files. This will allow you to use Bitmaps with alpha channels even if you don’t own paint software that allows you to edit alpha channels. Note that the files must have the same width and height.

Finally, you can mix-and-match bitmap images with procedural images in the same Bitmap, with the caveat that the width and height of a bitmap image always takes precedence over the width and height you may have previously specified for procedural images.

Once created, your Bitmap object will be available for use by other K-3D objects. The manner in which an object uses Bitmap objects will vary, although most will use it "through" the use of a Texture object.

tips:

When working with procedural bitmaps, make changes to the Bitmap Procedures while the Bitmap is set to a low resolution, such as 64 x 64, to speed up refreshes. Then, once you’ve found the settings you like, increase the size of the bitmap as required.

 

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