Graphic Gadgets

Overview:

This utility is designed to help you manipulate and save small, simple images for games or applications. The best part is that you can embed the images directly into any Just BASIC™ program you create!

Small, simple images often compress to 1/2 to 1/50th the original bitmap size. A perfect example of this is the file called "BG1.bmp" located in the Just BASIC™ "SPRITES" folder. It has a file size of 25,318 bytes, while the same image in .VRF format uses 2,306 bytes, for a better than 10 to 1 compression ratio!

You have a clean canvas nearly the size of the entire Graphic Gadgets window. This is intentional so that you can view and manipulate large bitmaps while viewing them in their entirety. The only thing that fills the screen besides your images are a few status messages to keep you informed as to what Graphic Gadgets is doing during the different processes it performs.

Capabilities:

· Load a Windows™ bitmap (.bmp) to display on screen

· Save the current screen to a Windows™ bitmap on disk

· Rotate a bitmap from 0 to 360 degrees

· Wrap a bitmap around an arc or circle

· Alpha Blend two bitmap images

· Flip a bitmap horizontally (make a mirror image of the bitmap)

· Flip a bitmap vertically (flip a bitmap upside down)

· Shear a bitmap horizontally (tilt the upper corners of bitmap left or right)

· Shear a bitmap vertically (ramp the right hand corner of bitmap up or down)

· Tile a bitmap image to cover the entire screen

· Convert a Windows™ bitmap to a text file containing RLE compressed data statements

· Convert a Windows™ bitmap to RLE encoded data statements which are placed on the Windows™ clipboard

· Convert a Windows™ bitmap to a ". VRF" image file (a RLE compressed form of the bitmap)

· Read data statements from a text file containing an encoded image and save as a Windows™ bitmap file

· Read data statements embedded in a program and display the encoded image on screen

· Convert an existing .VRF file to a text file of RLE encoded Data statements

· Convert an existing .VRF File to RLE encoded data statements which are placed on the Windows™ clipboard

· Convert an existing .VRF file to a Windows™ bitmap file which is then stored on disk

· Retrieve a .VRF file stored on disk and display on screen for browsing existing .VRF image files

· Convert an existing Windows™ bitmap to a "sprite mask" used by Just BASIC™

Limitations:

Graphic Gadgets won't take the place of PhotoShop™ or the Gimp™ and other high end image processing software, it just makes some image processing chores easier by putting them all in one convenient software package for Just BASIC™. It’s also nice to know that it’s coded in Just BASIC™ so you can modify to your heart’s content.

The graphic processing routines used in Graphic Gadgets are not intended for use in “real time” (i.e. use while a program is running). They are intended as helper functions to allow you to prepare the graphics for your application.

Graphic Gadgets won't take the place of a good compression program. Some images are too large or complex to benefit from the simple RLE encoding used. For these types of images use PNG's, GIF's, or even JPG's if slight image degradation is not an issue, then archive with your favorite compression program.

Images having more than 256 colors will not work with any of the RLE options in Graphic Gadgets. Images with more than 256 colors are usually too complex and would take up more storage space than the bitmap they are encoding, sometimes up to more than twice as much storage space!

You can and should, only use 24-bit images, which are the default images created by MS-Paint™. The limiting factor is that you can use only 256 colors out of the 16,777,216 colors available.

Acronyms

RGB – Red, Green, and Blue, where each primary color is assigned a brightness/intensity level from 0 to 255 in order to represent millions of colors on the display screen. All three values combined can express 16,777,216 different colors.

RLE - Run Length Encoding is a simple algorithm to compress images. It does so by encoding the "run length" of the same pixel color. If you have a black and white image 100x100 pixels where the top half of the picture is white and the other half black, each scan line with white pixels will be encoded as “100, 16777215” representing “100 pixels across using the same color” and “16777215” which is the RGB value for white. In similar fashion the black scan lines will be encoded as “100,0” representing “100 pixels across using the same color” and “0” which is the RGB value for black.

VRF - Vector RLE File is the file format created by this program. Because each pixel "run length" has two important components, direction and magnitude, hence the Vector part of the file name. If you add the color space of the "run length" then you have a 3-D vector. The RLE part is of course the name of the simple compression algorithm used to store these vectors on disk.

BASIC – Beginner’s All-Purpose Symbolic Instruction Code is the computer language used to write Graphic Gadgets. The name of the BASIC used to program Graphic Gadgets is called “Just BASIC™”.

The Menu Bar

Across the top of the Graphic Gadget window is the menu bar with the following menu choices:

File Image Options Special Effects Fast Sprite Mask! Help

File

Load Bitmap - Allows you to view bitmaps stored on disk on the display screen.

Save Bitmap - Captures whatever is currently on the display screen and saves the image to a bitmap file on disk.

Exit - Terminates the program.

Image Options

BMP to Data Text File – Converts a Windows™ bitmap to a text file containing data statements encoding the bitmap using RLE compression.