The Color Gradient Tool provides a UI for visualizing and experimenting with color gradients. By applying different curve functions to different color components, color gradients can range from basic color transitions to sophisticated spectral patterns. Select a color gradient in the "PRESETS" tab. The preview on the left will update. To tweak the parameters for a color gradient preset, use the "PARAMS" tab. Use the "PREVIEW COLOR GRADIENT" button to preview the changes you make. Move the mouse over the gradient preview on the left and a tooltip will display information about the color you're over, and if you click you will get the hex value of that color in a prompt dialog so you can copy it to the clipboard.