Photoshop-create a rule Selection

Now we want to turn the image into a blank space, just like creating a new image. This time, you may not pass the history record. Think about it, if the entire image is filled with white, does it achieve the same effect? Fill command in the menu [edit fill] [shift F5 〗. Use White in the content, the mode is normal, and the opacity is 100%. After confirmation, the entire image can be filled. For example.

This filling method is troublesome because you need to perform operations in the setting box. You can fill in the foreground with a shortcut key. It is set to "Alt Delete" or "alt backspace". backspace is the return key located above the Enter key.
In combination with the previous shortcut keys, the white filling method is: first press [d] to set the color to the default black and then white, then press "X" to change the foreground color to white, and then press "Alt Delete" to fill the foreground color. In fact, you can also use the shortcut key to directly fill in the background color. It is CTRL delete or Ctrl backspace. Therefore, the above operation can be simplified to [d] and CTRL Delete 〗.

Three important parts of Photoshop are selection, layer, and path. These three are the essence of Photoshop.
First, we define two concepts:
1: The selected area is closed. It can be in any shape, but it must be closed. No open constituency exists.
2: Once a constituency is created, most operations are only effective within the constituency range. To perform a full graph operation, you must cancel the selection.

Most of the selections in Photoshop are based on selection tools. A total of 8 tools are selected, which are concentrated on the top of the toolbar. Rectangular Box selection tool, elliptical box selection tool, single-line box selection tool, single-column box selection tool, set cable tool, polygon set cable tool, magnetic set cable tool, magic wand tool. The first four are rule selection tools.

Let's take a look at how to create a constituency to adjust some colors. Open an image in Photoshop, select the Rectangular Box selection tool or shift m in the toolbar, and confirm the public column settings as shown in.

Drag and draw a rectangular area in the image, and then you will see a dotted line flowing around the area. The left figure is shown below. In this way, we have created a selection area for the rectangle, and the dotted line of the flow is the representation of the selection area by Photoshop. The area within the dotted line is the constituency. If you press ESC during the selection process, this selection will be canceled.
Then, you can use the color adjustment tool to adjust the image in the selected area. The right figure below shows how to increase the brightness to + 70 by using brightness/contrast. The brightness/contrast adjustment tool is stored in [image adjustment. Most of Photoshop's color adjustment tools can be found here.
Note that the selected area still exists after adjustment. In this case, other color adjustment tools are only available for this area.

As mentioned above, once a constituency is set up, almost all operations are limited to the constituency. This also includes the paint brush tool we have learned before. If you use a paint brush to draw in an image at this time, only the selected area will show the effect of the strokes. The left figure is shown below.
It also includes filling. At this time, filling the foreground color is only valid within the selected range. See the following picture on the right. Do you still remember the shortcut key for filling in the foreground color? It is "Alt Delete" or "alt backspace 〗.

The selected area can be moved after it is created by pressing the left mouse button in the selected area and dragging it to the new position (for example, dragging from the red arrow to the Green Arrow ). The cursor can be moved only when the selection tool is used and the calculation method is the new selection area. You can press the Shift key to maintain the horizontal, vertical, or 45-degree orientation during movement. The size of the removed constituency remains unchanged. For example.