| ## Colors ArtPaint offers many possibilities for selecting colors. Colors can be picked from a user-defined color set, or they can be mixed with sliders using one of the various supplied color-models or the color can be picked straight from the image using the color selector -tool. ### Foreground- and Background-color Foreground-color is the color that is used by the tools to do the drawing. The background color is used by the eraser-tool and is used as the color to clear the image to. Also some add-ons might use the background color. If the color is selected with the primary mouse button it will become the foreground-color. If it is selected with some other mouse button it will become the background-color. ### Color sets Color sets are collections of colors that can be edited. This way the most frequently needed colors can be stored. Each color set can have between 8 to 64 colors. Color sets can be also saved to disk for later use. ### Color-window Color-window is the place where new colors can be created with sliders and color-sets can be modified or new sets created. Figure 1 shows what the color-window looks like.
Figure 1: Color-window.
The left side of the color-window contains a grid which contains some colors. The colors in this grid are called a color-set. The long bars in the middle are color-sliders that are used to adjust the color. On the right is a box that reflects the currently adjusted color. On the left side of the color-sliders are four letters indicating what color-model is being used. The lowest letter is always 'A', which stands for alpha. Alpha is rather technical term, but it actually means just transparency of the color. If the slider is on the left, then the color is fully transparent, if the slider is on the right, the color is fully visible. A transparent color will have a black-and-white checkerboard pattern that shows underneath the color. The top three sliders control how the color looks like. What these sliders do depend on the selected color-model. The color-model can be changed from color-window's Mode-menu. The different color-models are summarized below: RGB Red, Green and Blue. This model allows the color to be composed of these three basic colors. These components are the same as are the primitive components on a typical monitor's display. Sometimes this model is referred to as being an additive model. CMY Cyan, Magenta and Yellow. This model allows the color to be composed of three basic colors. This is exactly the opposite as the RGB-model. This model is often used in printing devices (with the additional component K for black) and is also called a subtractive model. HSV Hue, Saturation, Value. This model composes the image using three basic properties of color. Hue controls what is the basic hue for the color. Saturation controls how saturated the color is, and value controls the brightness of the color. This is often used in painting applications as it is found to be more intuitive than many other color-spaces. YIQ This model is the same as is used in North American TV transmissions (NTSC). Y component controls the luminance of the color while I and Q components control the hue of the color. YUV This model is the same as is used in European TV transmissions (PAL). Y component controls the luminance of the color while U and V components control the hue of the color. BeOS Controller This model is the standard BeOS color controller. If you are using a 32-bit screen depth it is similar to RGB-control, but if you are using an 8-bit depth, it will display the 256 BeOS system colors. You can adjust all of the color sliders (but not alpha) at once to the same value by pressing down left shift before sliding. To adjust the values relative to each other, press down left control instead. This is especially useful with the RGB- and CMY-models. The color sets can be adjusted by clicking on one of the colors and then adjusting the color with a slider. The color can also be copied from color set to another location by clicking on the color and dragging it there. The Set-menu in the color-window allows you to create new color-sets and to delete existing ones. It also allows you to save the sets to disk. The current state of the sets is always saved also automatically when the program is quit. The two arrows below the color set allow for changing between different color sets. The active color set along with the arrows is duplicated in the status-bar of every paint-window to allow quicker selection of colors.