Polygon Modeling Basics Chapter 1 - Vertices

Transcription

1 Polygon Modeling Basics Chapter 1 - Vertices In this tutorial we will cover the basic tools necessary for Polygon Modeling using the Vertex sub-object selection. It is less of a how to tutorial and more of a guide to the tools and what they do both visually and verbally. First step as always, open 3DS Max and go to the create tab, geometry should already be visible, we are going to make a box. Drag out your box in the Top Viewport close to the center of your grid where the two black lines meet in the middle. It doesn't matter what size your box is for now, we are going to change the parameters in a moment. Once you have created a box, go to the Modify tab next to your create tab in the menu on the right hand side of the screen.

2 Make sure your box is selected and then change the settings for the box you just drug out to 75 length, 75 width, and 50 height. Then make sure the Segments each have 5 next to length, width, and height. Your settings should look like this: Next we are going to want to see our segments on the box in our perspective viewport so we know what we are going to be manipulating.

3 In the top corner of your perspective viewport, see where it says [Smooth + Highlights]. If you are running anything over 3DS Max 2010 then your Perspective viewport will say [Realistic]. Click on the Smooth + Highlights words to get the display menu for this viewport. We want to activate Edged Faces towards the bottom of the first list menu. Select it like above. Your box should now show up with all of its edges and polygons showing in the viewport display.

4 Now that we can see what we are doing, we can go ahead and turn this box into an editable poly. There are two methods for this. We can add an Edit Poly from the Modifier list. This keeps the original box settings. If you aren't sure that you are going to like these original settings, then use the Edit Poly modifier so the box still exists and you can go back and edit your original object > This method of creating the editable poly will also give you the Edit Poly Mode. You can actually animate the changes you've made to your model using the Edit Poly modifier.

5 If you are not planning to animate the model changing itself in this manner, then you can clean up your modifier stack by selecting your box, right clicking to bring up the right click menu, and find the Convert To: option all the way at the bottom. Hovering over this brings up a secondary menu, where you can convert any object into an Editable Mesh (not quite as useful these days), Editable Poly (That's the one we want), Editable Patch, and NURBS. Those are another subject all together so we'll stick to the Editable Poly selection. Most of the time you aren't going to want to animate your modeling changes, if that is going to be the case then keep your modifier stack clean by just converting your object into an Editable Poly via the convert to option.

6 Once you have turned your Box into an editable poly via one of those methods. It's your choice. You should have access to all the tools that come along with the Editable Poly available to you on the Modifier tab. Here I have just stretched out the command panel to show you how many settings and options you have to work with. Quite a few options have suddenly become available to you. Now is not the time to panic.

7 Now is the time to experiment. In combination with the standard Select, Move, Rotate, and Scale tools (you should have already read the tutorial on those by now if you are not familiar with them.) We can use these options to manipulate our object and turn it into anything you imagination can come up with. We'll start with our Selection options. Click the small + sign next to your Editable Poly to open up your sub-object selections. ---> ---> You will see a list of words: Vertex, Edge, Border, Polygon, and Element.

8 Also down in your settings, you will see the Selection rollout. It also has a + or - sign next to the rollout label. If this menu is closed then click the plus sign to open it. Once you can see your Selection settings rollout menu, you will notice first the row of bright red symbols. These symbols and the words above in your modifier stack are the sub-objects of your Editable Poly. The entire model (in our case it still looks like a box) is the Object, and the Vertex, Edge, Border, Polygon, and Elements are its sub-objects. Roll over the symbols and you will see the corresponding words that they represent.

9 By clicking on either the word, or the symbol it will allow you to manipulate that sub-object. If we click the Vertex symbol (the three dots) you will notice that the word Vertex is also Highlighted. You will be going back and forth between these selections as you create your 3D Models. Each sub-object selection will change the settings below it to fit the selection. So that large list of settings and tools we saw before, is actually quite a lot larger based on the sub-object you are selecting. We will start at the beginning here. The Vertex selection - The symbol is the three dots, and the corresponding word is Vertex. A vertex is the point where two to 4 edges cross or connect to each other. Select your vertex sub-object selection mode, by clicking either it's symbol in the settings, or the word Vertex in the modifier stack, as shown in the above image.

10 You will notice that a bunch of blue dots have shown up on your model (box). These blue points on your model, are the vertices. Notice that at the corner of each rectangular polygon created by the segments of our original box settings, has a vertex. Using your Select, Move, Rotate, and Scale tools, you can select one or more of these vertices. You can also manipulate them by moving one or more vertices, rotating them, or scaling them up or down. The basic shape object you had before technically no longer exists. It is now putty in your hands, and you are a sculptor. Select your move tool from the Main toolbar at the top of your screen. Then select one of the vertices on your polygon model (It used to be a box! Now it's a polygon model).

11 You should notice that your selected vertex turned red. You can select one or more vertices by holding the Ctrl. key on your keyboard and clicking on another unselected vertex. You can unselect a vertex and remove it from your selection by holding Alt and clicking on it. Try adding the vertex to the right of the currently selected vertex. Hold down Ctrl, and click on the vertex. Side Note - **If you are having trouble seeing the vertices, you may want to change the color of your box to something that contrasts blue and red a little more. My purple box was bothering me, so I changed it to a very light green and now my vertices show up much nicer.** If you held Ctrl and clicked the vertex next to the currently selected, you should now have two red vertices in your current selection. Try moving your mouse over the move tool icon, hover over the shaft of the green Y axis arrow only, and then click and drag your mouse. Pulling your two selected vertices along with your mouse movement. By selecting the Y axis arrow only, you can move the vertices either Into the Box by dragging left, or away from the box by dragging right.

12 You can now move the vertices to new locations, creating new shapes. Our box is now being edited at its smallest level of detail. Experiment with the selection tool, dragging selection lines around a region of vertices. Then experiment with the move tool further, the rotate tool, and the scale tool to get a feel for what these tools can do for your vertex sub-object selection. When you are finished experimenting, read on further I have Ctrl + Z, Undone by fooling around, so we still have our basic box shape. Head back to the right, where we saw all those settings on the Modify tab. Let's get the basics of the vertex selection tools. The selection options change based on which sub-object you have selected. Some will be grayed out and unclickable unless you are on the sub-object selection that fits it's requirements. We can only select the Ignore Backfacing option while in Select Vertex mode. This check box will make it so that you can't <--- select vertices on the other side of your model. It will ignore them. Very useful if you find your model getting altered in places you are not trying to work on. <--- The Shrink and Grow buttons are also available to us. Select 1 vertex on your model, then click on the Grow button. It selects more vertices exponentially starting with 1 in all three directions along the x, y, z axis. The more you click Grow, the more vertices all around it will be selected for you. The Shrink object does the opposite of grow, if you click it now, you will unselect all of the new vertices that Grow gave you. Ring and Loop are not available for Vertex selection mode.

13 Next, open the Soft Selection rollout, directly underneath the Selection tools we were just going over, by clicking the + sign. If it is already open, then you are already there. <--- Click on the Use Soft Selection Check Box to turn on Soft Selection. Soft Selection allows us to manipulate on object using a falloff curve. This means that the strength of how much the selected vertex is pulled will also pull the vertices around it depending on the size of your falloff. The amount these vertices are pulled will diminish the farther away from the main selected vertex. Once you have turned on Soft Selection, let's try it out.

14 Click on a vertex in the middle of you model. The clicked vertex still shows up red, but you now notice a rainbow of other colors spreading out from the vertex you selected. The warmer the color, the more it will be pulled when you move this vertex, the cooler the color the less the vertex will be pulled. Red is the strongest, Dark blue is the weakest, and white/normal blue vertex color means it won't be pulled at all. Try adding the 4 vertices in the middle of the front side of your box. Hold Ctrl and click them one by one until they all turn red. Notice that whatever you have actually selected, will turn red, and the rainbow of colors will adjust to make your selections the epicenter of its diminishing effects.

15 Now try getting your Move Tool, and Pulling those 4 vertices toward you on the Green Arrow (Y Axis) The red vertices pull all the way to where you want them, and as the colors cool down to deep blue, the other colors follow behind those red vertices. Making your modification soften, you have created a soft bump, rather than a hard edged modification. ** I have undone this change to bring our regular box back.** <---- Adjusting the falloff number to bigger or smaller, will shrink or grow your rainbow effect to give you more control over which vertices you want to be pulled along with your selection. Higher the number, the large area the rainbow selection pulls. The Pinch number doesn't change how far your soft selection reaches, but instead a higher number adjusts the rainbow effect to make your warm colors cover a smaller area. Effectively creating a pinch effect, instead of an evenly spread effect. The Bubble number does the opposite of pinch. The higher the number, the larger your warm colors will spread. It does not change how far the soft selection reaches like the Falloff. Just the rainbow effect to make the pulled vertices with a bubble effect, as more vertices will follow your selection more closely. Try experiment with these numbers to see how the rainbow changes, and how pulling the vertices out change when you adjust these three numbers. Notice both the rainbow colors on your model, as well as the bell curve graph under the numbers to see how it will affect your selections.

16 The next button down is the Shaded Face Toggle, it is directly under your bell curve graph. Pressing this button will toggle on a full rainbow effect. Try it, and see what it does to your model and the vertices you have selected. The rainbow effect is much more visible with this on, but it can also obscure what is actually happening to your model, so use it if you need it, but always toggle back and forth to see the changes and make sure it's what you wanted. Under that you see a checkbox, the Lock Soft Selection. If you check this box it will lock your soft selection in place. You will still be able to select other vertices and move them, but soft selection will always follow your original selection and won't add a soft selection effect to any other vertices you select. Experiment with it, but remember to turn it off when you are finished or you might run into trouble. Undo any changes you have made, so our box is still looking like a box. Under the Lock Soft Selection, you have the Paint Soft Selection settings.

17 With the paint button pressed, you can add to your selection, and increase the warm color values. Try turning Paint on heading over to your model. You will see a new icon, the blue circle with crosshairs is the paint brush icon. If you click and drag, you will notice that anything you paint on top of becomes part of the soft selection, if you paint on the current soft selection, it will increase the warmer color values. This is a great way of controlling your soft selection, but be careful. It can be hard to undo extreme changes if you don't like the end result. The blur button does the almost opposite of the Paint option. It softens the warmer colors, to "blur" the lines between the soft selection. It is great for making your soft selection smoother for the end result when you push or pull your selections. It will increase the size of the falloff, but it will only add dark blue to added selections. The Revert brush, will allow you to "revert" to the previous Paint and Blur brushes, It is sort of... an undo brush. Below the three brush types, you have the brush settings. Selection Value, Brush Size, and Brush Strength. Selection Value increases the value of your brushes as they go over new selection areas on your model. It only goes from 0 to 1. The brush size will adjust the size of the circle icon that you use as a brush. Increasing or decreasing the area the brush hits as you paint. The brush strength goes from 0 to 1 as well, increasing, or decreasing the amount of warm or cool colors you add to your selection. The brush option button, will bring up the brush options dialogue box. This is a complex settings window, that we won't get into in this tutorial. So just keep with the above tools for now. That is it for the Soft Selection settings. When you are finished with soft selection, always remember to uncheck the "Use Soft Selection" checkbox to turn off your rainbow colors. Undo any changes, so our box remains.

18 You can now close the Soft Selection rollout, by clicking the - sign next to Soft Selection label. Our next topic is the Edit Vertices Rollout, below Soft Selection. Find it and open it up. You might spend a lot of time in this rollout. Here we can change, remove, break apart, weld together, extrude, or round out our vertices. Start by selecting 1 vertex on your box model, then click the Remove button in the Edit Vertices rollout. This button will get rid of any vertex you may not need. Notice though, as it also remove any edges that were attached to the vertex. This can be useful if you are trying to clear an area for making anything from... a bigger window in a room, to getting rid of extra vertices that you may have accidentally added to your model that you don't need. Always remember that working with 4 sided polygons is the best, 3 is ok when necessary, but polygons containing more sides than that, can cause you trouble. By removing that vertex we have created a larger polygon, with 8 sides. Removing vertices is a useful tool, just make sure you are using it the right way. Undo the removal of this vertex.

19 This time, with the same vertex selected, hit the delete key on your keyboard. Now notice that this method of removing a vertex will delete not only the vertex and the edges it is connected to, but it also removes all the polygon faces leaving a hole in our model. This method of deleting a vertex can work for you just fine, if you want a hole in your model... maybe it's a window! Undo the deletion of a vertex. Remember the differences between removing a vertex, and deleting a vertex. It could serve you well. Next is the Break button. Select our single vertex again if it is not selected already. and click the break button. It appears as though nothing has happened to our model at all!

20 In reality, something drastic has actually happened. Try clicking on the same vertex we just broke, and moving it away from our box. Our single vertex has broken into 4 vertices at the corner of each connecting polygon. Break will separate the corners of the polygons from being welded together like they were before. Under the Break button, is the Weld button! it does the opposite of break, but needs at least two vertices selected at the same time to work. It will attempt to weld the selected vertices together based on how far apart they are.

21 With the weld tool, you have two options. Notice the button that says Weld, and next to it is another button, this is the symbol for a settings dialogue box. You will notice it next to many buttons in the edit poly settings group. By clicking the button that says weld. The tool will use the default settings and attempt to weld your vertices. If they are very close to each other, this will be sufficient. If you don't have the selected vertices close enough, you will need to click on the symbol for the Weld Settings dialogue box. Click on two of the vertices that we just broke apart

22 Once you have two vertices selected, click on the Weld settings dialogue button. The Weld Settings dialogue box will appear. Here you can see your options for the weld. If you selected 2 vertices, and tried to weld them but it did not work, it is most likely because the Weld Threshold: was set too low. The Weld Threshold is how close the vertices have to be to each other in order for the Weld to recognize what you want it to do. The two vertices I have selected are too far from each other to weld. I can tell this because of the area below the Weld Threshold. It gives you the Number of Vertices on your entire model. Then there is a Before and After number. This is Before the Weld, and After the weld. We can tell that after the weld, there is the same amount of vertices in the model as before, 155 in both areas. If the weld was going to work, the After number should be reduced by one, as 2 vertices welded together become 1 vertices. So try increasing the threshold number, until you see the After number go down by 1. It took me almost to the number 9.0 before my vertices were within the Weld Threshold. Notice that my After number is 154 now, and the before is still 155.

23 This lets me know that my weld is working. The only problem with this method of getting your weld to grab the other vertex, is that the weld will occur between the two vertices. This may leave your model with unsightly lumps that you will have to correct by hand. Always remember that the closer together your vertices are, the better your welds will work for you. Just because you CAN weld two vertices together that are very far apart, doesn't always mean you SHOULD weld them this way. Move your vertices as close together as you can before adjusting the threshold in the weld settings. If you are good enough, 0.1 should work without adjusting the settings. This is pretty hard to accomplish though, so close usually works good enough. Horseshoes, Hand grenades, and Vertex welds! Now that we know how Weld and Break work, let's try to undo all the changes we made, so our box is back to being whole again. Our next button is the Extrude button, next to Weld on the left. Extrude is available throughout all the sub-object selections. It is a very important tool, and you will use it quite often. I can say however, that I rarely use it while in the Vertex sub-object selection.

24 Click on a vertex on your box then click on the Extrude button (not the settings dialogue yet, that's next) Once the Extrude button is pressed down, go over to your model with the vertex you had selected. Click and drag on the vertex and push your mouse up on the mousepad. Extrude pulls your selection away from the model, and creates new polygons behind it. This is why Extrude is so useful when you are modeling objects or characters. Creating new polygons in out and away from their starting points allows us to build upon the basic shape we started with. Be careful when using extrude vertex however, as using it creates points, as well as 3 sided polygons in its wake. Remember we like to try our best to 4 sided polygons, also referred to often as Quads. It is a handy tool, and we will use it much more often in the other sub-object selections like Edge and Polygon selections. Undo the change to revert to our basic shaped box. Keep the vertex you had selected and this time go click on the dialogue box settings icon (the symbol next to the Extrude button, just like we used for the weld.)

25 The Extrude Vertices Dialogue box will appear on your screen. By adjusting the extrude using these number sliders you have more exact control over how far out, and how far the base is spread. Move these numbers up and down and look at your model, it will be previewing the change for you, but it won't be set until you hit either the Apply or the Ok button. The Apply will apply the change and then start a new one, the Ok button applies the change and then closes the dialogue box. If you hit Apply and Then Ok, you will have created two extrudes accidentally. Always click one or the other, if you want more than one extrude that is fine, but when you are done using the apply button, hit Cancel instead of Ok to close your dialogue box and avoid accidental extrusions. After you are done exploring the Extrude dialogue number settings, click Cancel. This should make it so that no changes have been accepted and your box will be back to the original shape. Next is the Chamfer button. Click the Chamfer button to turn it on, and then go and click and drag up on a vertex.

26 The Chamfer button will create new polygons, but will not pull them away from their origin points. The box stays a box, but the single vertex that was there, is not 4 vertices spread apart between the other polygons. This tool is great for rounding things out like corners and edges. Undo your chamfer so the box looks like it's old self again. Then be sure to click Chamfer again if needed to turn off the button. This time, select one of the vertices on the corners of your box, and go click on the Chamfer settings Dialogue symbol button next to the Chamfer button. The Chamfer Vertices dialogue settings window will appear on your screen. There are two options in Vertex chamfer settings. The Amount and a checkbox that says Open. The amount as you can notice on your model as you move this number up and down, changes how far apart the vertex is split apart. It makes the new polygon bigger or smaller. Notice that when this is done on a corner using vertex chamfer, that it "rounds" out the corner and there is no more sharp edge to our box. Next Click the Open box. Notice that instead of a new polygon, it has created a hole in your model. Click Cancel to avoid any actual changes to our box model. Next up, the Target Weld button. The Target Weld allows you to click on one vertex and then drag out a dotted line towards another vertex as long as they are connected by an edge.

27 Clicking on one, dragging the dotted line to another vertex and clicking on the second vertex will weld these vertices together at the destination(where you drug the dotted line to). Undo any changes you made while experimenting with the Target Weld. Next is the Connect button. This button will draw an edge line between any two or more vertices you have selected, as long as there isn't an edge line already in between the vertices. Select two vertices at opposite corners of a polygon like this:

28 Once you have selected these two vertices, click the connect button and watch how it connects the dots on your model. This option is more useful when using it in other sub-object selections, as again, it creates more 3 sided polygons when going from vertex to vertex. However, it can be useful when your model has some 5 or more sided polygons, to cut them in two and create quads. The Remove Isolated Vertices is used as a cleanup, in case you accidentally created vertices. This can happen if you click the wrong tool, or accidentally hold shift while moving a vertex. Holding shift is the shortcut for copying something, in almost every object or sub-object. Clicking on the Remove Isolated Verts button, will remove these pesky accidents.

29 The Remove Unused Map Verts is a texturing problem that can occur when using things like the UVW Unwrap modifier. We won't talk about it in this guide. We are done with the Edit Vertices rollout settings. All of the settings talked about above, when used in combination with the basic select, move, rotate, and scale tools can be used to adjust the shape of your model by modifying the vertices in your model. The rest of the rollouts are all the same whether you are in Vertex Selection mode or any of the others like Edge or Polygon, we'll talk about them more in the next few chapters of Polygon Modeling Basics. I hope this tutorial has cleared up a few things and shown you what you can do by editing vertices in your 3D Models. **Keep this box scene for the next chapter, when we move over and talk about the all important Edges sub-object selection settings!**