hello everyone, in this video I'm going to show you several basic tools for drawing and modification these tools are very useful and you are going to use them to complete your first drawing assignment for this week okay let's first go to the status bar on the "right" (slip) bottom of your screen if you put the cursor near one of those icons, it will give you the name, like grid, snap mode, ortho mode, polar tracking, object snap tracking, and the object snap -osnap let's first take a look at the first two icons and see what they can do for the first icon you can turn on and off the grid mode by clicking on it when you turn it on you will see the grid lines on your screen and same thing for the snap mode when you turn it on, your drawing will be automatically snapped to the grid let's first draw a line and see what will happen simply type in "L" press enter to call the line tool or you can also get it quickly on the top of your drawing toolbars you'll see that the end point of your line will be automatically snapped on one of the nodes on the background mesh, and your cursor won't be moved to anywhere else other than one of the nodes on the background mesh okay so now let's turn off the snap mode and see what will happen now you can see that I can move my cursor to anywhere on the grid it doesn't have to be a horizontal or vertical lines that has to follow the grid lines and you can draw the lines along any directions you can left click once to determine each endpoint of a line segment and press enter to complete the line drawing command okay now if you want to clean up the sketch or remove the lines just simply double click anywhere on the screen and draw a rectangle double click, okay, draw a rectangle and you can circle up all the line segments and then press delete button on the keyboard so we remove all the lines okay now let's take a look at the next two important commands on the status bar they are called orthomode and polar tracking actually you can only use one of them at a time let's first turn on the also mode and see what will happen quickly call the line command and now you can see that no matter how I move my cursor, you can only draw the vertical or horizontal line with the orthomode turned on, and even you also have the snap mode turned on you cannot draw any oblique line okay now let's click the other icon and turn on the portal tracking, and see what will happen okay before we try this polar tracking let me delete all the line segment okay, now call the line command again now we can see that with the polar tracking on, we can actually draw some oblique line with the snap mode on my cursor will be automatically snapped on one of those grids, but the line we are going to draw does not necessary to be in vertical or horizontal way it can be also in a oblique way with any angle so now you can see that I'm drawing three line segments, which form a triangle okay now let's clean the screen and try some other tools you can double click and make a triangle region and touch the triangle object and press delete to delete them okay, let's take a look at the other two icons on the status bar Auto snap and osnap and here the object snap is also called osnap now use the line tool again you may select your first point and direct the line in any direction you want in this case I would like my line to be drawn in 90 degree with a specific lens so simply type in 5 in the 90 degree direction press enter, and now you gotta a line with a specific length of five units to verify this, we can go to the top of the dimension toolbar, select the "linear" dimension tool you can see that your cursor is automatically selecting the two endpoints of this line and the dimension shows that it is five units in the vertical Direction now let's use the same way to draw another line with 10 units and use the osnap tool to automatically select the endpoints of the first line so we can draw another right triangle now we can select the linear dimension tool on the dimension toolbar again, and select the end point automatically with the old snap tool turn down, and you can see that the bottom side is 10 units, now, how about I also want to show the dimension of the hypotenuse? this time you can go to the second icon on the dimension tool this tool actually can help you to create an aligned linear dimension so you can see that this hypotenuse is 11.1803 unit, which actually follows the Pythagorean law of this right triangle now another thing I want to show you with this osnap tool is actually you can see that your cursor can automatically catch the midpoint with the osnap tool, so that we can draw another smaller triangle right triangle to connect the three midpoints of the three sides of the larger triangle here another thing I need your attention is that on the slide-up menu of the osnap, make sure you select all the important objects that you want to automatically catch by your cursor, say, if you select the perpendicular points on the osnap so this osnap tool can help you automatically capture the perpendicular intersection on one of the side let's use a line tool to draw a perpendicular line this time type in the line command again and start from the bottom vertex and guide your cursor to somewhere along the hypotenuse your cursor will automatically catch the perpendicular points to help you draw a perpendicular line okay now I'm gonna show you another useful tool called "circle" on the drawing toolbar, after you select that and define the center you can type in the value for the radius and press enter then we can draw a circle with the desired radius now let's see how we can duplicate this circle by using the copy tool go to the modify toolbar and click the second icon that's the "copy" and select the circle object then it asks you to specify a base point so start from the base point you can make a different distance to make up one copy or multiple copy of this circle in different directions AutoCAD will show some green dash line to guide your cursor to make the duplication along vertical or horizontal way after you specify a base point for the duplication after we made those duplication we can simply right click, and press enter to finish the drawing now if you want to move this drawing to the side and make more space on your screen to draw some other thing you can select the pen tool on the standard toolbar or simply press down your mouse roller and move around this is the expressway to move your drawing planner to the screen you're gonna mainly use the circle tool and the copy tool to complete the drawing we have another video to give you more details about this homework drawing of the Snowman so please watch the next video and complete the homework for this week also please practice more using your own AutoCAD and feel free to attend our help sessions throughout the week if you have any question thanks for watching