Tuesday, April 22, 2014

Blender Tip Smooth Operator

If you want, start humming along with Smooth Operator since apparently setting something to music helps you remember stuff.

Here is a very nice time saving Blender trick I decided to share as a mini one image tutorial. I use the Smooth operator on the Specials menu quite a bit to average out the size of my polys before sculpting, but it was also the perfect trick here to avoid sculpting.  

This shows my somewhat patchy patching job after joining the top and bottom half of a body on an imported obj. I am also working on only half the body to save time, then planning to apply a mirror modifier. I could head into sculpt mode to smooth this out with a brush, but my intended use of a mirror mod means this is not quite as straightforward as it sounds. I would need to apply the mirror mod first, then divide the mesh again if I had further work planned. I could also slowly, using proportional edit maybe, move the verts around until this area made a nice smooth transition. puhleeze.

Instead, use C for circle select to quickly grab some faces (smooth works on edges and verts too, but I find Face Selection mode makes it easiest to see what I'm doing on this). Then press W to bring up Blender's Specials menu, choose Smooth. Now the super timer saver step is press the F6 key to get the Last Operator pop up where you can control the amount of smoothing (number of times that smooth is applied) using the slider. Bonus, in 2.7 you can also choose which axis to apply smoothing to.

Blender gets better and faster all the time.   

Thursday, April 17, 2014

Ebbe Linden & Education In Second Life

Ok, so this is a bit off the topic of content creation, but certainly fits in with the general Some Of My Best Friends Are Pixels thang I got goin', well the pixels part anyway.

So as a frequent reader & long time fan of Strawberry Singh's blog I sometimes almost do one of her infamous and usually super clever Blogger Meme Challenges, but then I don't. This time, I am bustin' out, and taking Flat Ebbe on a tour since it's just too good an opportunity to miss.

That's Flat Ebbe & me at Builders Brewery, a school, help group, sandbox and all round educational nexus in Second Life. I knew that Ebbe would like it here since as I understand it from his public statements so far he is pretty keen to reestablish Second Life as a viable forum and platform for education. 
Me too! 

So in keeping with the meme theme, here are the three things I would like to tell Ebbe:

1. I was genuinely thrilled to hear that education in SL was on someone's agenda again. I hope that the agenda is broad enough to include support for in world educators and learners as well as attracting brick and mortar institutions and students from the outside world. 

Now two of my current pet peeves - both related to content creation and specifically to streaming costs and how Land Impact is calculated. Although I realize this is probably way below Ebbe's pay grade, I bet he knows someone who knows how to fix this kind of thing.  

2. First, the Land Impact algorithm for mesh objects could be improved. It doesn't really give a fair calculation of streaming cost based on volume, because as soon as an object pokes outside of a hypothetical cube, the LI goes up as though the object in question is now occupying a proportionally greater chunk of screen real estate. But in the case of a long skinny object for instance, this is a misreading. Specifically, there is no way that a 500 tri tree trunk should cost more in Land Impact than a 5000 tri tree stump, no matter how tall the trunk in question is.

2b. Second, I guess it probably saved time to make all materials and Alpha Modes invoke a streaming cost calculation, but Alpha Masking, which is super fast and potentially a great lag reducer should NOT raise the LI no matter what surface it is used on. Specifically, as it stands now, changing the Alpha Blend on any sculptie plant (the vast majority of plants in SL are sculpties) would significantly reduce lag and render times in those areas, yet due to streaming costs calculation, would have the effect of doubling the prim allowance required. 

3. Love that you're engaged and engaging, maybe restart the blog as a semi regular what's new. Lot's of tiny stuff changes and often for the better, but goes unnoticed.     

Wednesday, April 16, 2014

Blender Limited Dissolve ~ A love Letter

I confess I feel a bit like I am revealing a dirty secret, but it's such a recent and delicious discovery for me that I wrote a love letter (illustrated of course) to a Blender operator and I'm going to show you my solution to a workflow problem that has bugged me all week.

I've been sculpting and painting these cute little figures in ZBrush but then taking them back to Blender to get ready for SL. Now I don't know if you know this, but ZBrush tends to encourage some pretty high poly work, certainly way beyond what Second Life is prepared to allow.

He's cute, right, but he and his little friends have given me nothing but grief at the finishing up for Second Life stage. I tried exporting subdiv 1 from ZBrush, about 4-5k polys - reasonable for SL, but barely enough to wear their normal maps which are supposed to preserve details such as facial features. Then there were the textures to worry about. I polypainted them in ZBrush, which being ZBrush uses an equation something like 1 texture pixel per poly, so since a 1024 has more than a million pixels, you better have more than a million polys while you paint. But woe to anyone who thinks she can drop that same texture on a subdiv 1 and still expect to see any detail let alone pretty. Subdiv 2 wasn't much better, and now I was spending a significant chunk of time trying to reduce the face count before upload. If he was jewelery or a worn item, of course, SL being SL, I could get away with as much as the uploader would allow... cough. This would not be the responsible thing to do, but desperate times call for desperate measures.

And I think I found the ideal desperate measure - Limited Dissolve in Blender. I am head over heels in love with it. 

First let's be clear - this is not exactly sound retopology practice. I'm not even sure some of what I ended up with deserves the name topology. The only way you might end up wanting to use this over say, removing edge loops or doing retopo was if you happened to have some very high poly models that already have polypainted textures and UV maps, meaning it's a bit late for retopo, and a bit dense to be bothering with removing edge loops, and too soon to decimate.

Now I know what you're thinking, maybe that whole work flow is flawed, maybe I should give up polypainting textures in ZBrush and go back to texture in Blender or Photoshop after retopo but, but, but sob, I just can't.

So if you can't keep from sculpting and polypainting but you still want to strip away enough geometry to make a viable SL trinket, here's my dirty secret love letter to Limited Dissolve.

Ok, if a one button reduction from 171 faces to 5 isn't enough to make you all tingly, I am truly surprised you read this far. If you are feeling pretty excited try to hang on a bit longer so you'll know some of what to expect on the honeymoon.

So far I have no way to predict which areas will work first try, or what sort of angle will produce the desired results. More careful study might answer those questions, but it all happens so fast and it's so easy to tweak, that the only dilemma is what you will say when someone points and laughs at your huge randomly placed ngons.


Now you know my dirty secret love of Limited Dissolve.
Sign me 
Desperately Seeking Less Geometry,

garvie garzo

Thursday, April 10, 2014

Blender First Steps Tutorial

This is a class I wrote for Builders Brewery School in Second Life last summer. It's been popular and it's been tons of fun to teach. I am putting it and the slides on line now for easier access for me, for current students, and for anyone who for whatever reason was unable to attend the inworld class. I hope it's useful for beginner Blender users.

The point of the class was not to teach Blender per se, but just to provide enough familiarity so that students could start box modeling as soon as possible. So many people I talked to while getting ready to do this class told me that they were planning to learn this program or that program so that they could start making mesh for Second Life. I think that's a pretty bad approach myself. Better to just start using a program and learn to do by doing. Anyway, that's what I told the BB students in SL, and these are the slides I showed so that they could get to know their new tool as a tool for beginner modeling.

Allow me to introduce Blender's opening 3D scene (everything inside the orange dotted line). It's not that exciting really, the infamous default cube, and some black stick outline thingies. 
Two things worth noting here: 
First, T is a Typically brilliant Blender shortcut, using the first initial of the item or operator it is a command for. In this case typing t will open the Tool shelf. Pressing T again will close the tool shelf. A single easy to remember letter to toggle open or closed. Blender also usually underlines the relevant shortcut letter for each operation on menus as I have done on the slide.
Second, That tiny icon indicating that the main window is set to the 3D viewport conceals a bunch of other icons for other window/editor options. In Blender you can change the contents of any editor window to any other kind of editor. So you can rebuild the UI to suit your style, your eyesight or your current project.   

The Outliner window looks and sounds a bit technical, but it's really very useful. It will always list everything in your scene even when the object is hidden from view or on a different layer. Right now it lists the 3 things we have in our scene and it highlights the word Cube because the cube is currently selected.

Our first mission is to select the camera and the lamp so that we can move them out of the way. This is a frustrating moment for new Blender users, because a left click seems to do nothing but move that irritating little target around.

In Blender, you right click to select.

To select the camera, right click on it, to add to that selection, hold shift and right click the lamp.

You can also select things from the list in the Outliner window. In this case, a regular left click will highlight them, and holding shift will add to the selection.

And you can select things by press a to select All. A is another toggle style shortcut, A to select All, and a again to deselect All. That last is very handy when modeling, to make sure you don't accidentally have something selected that shouldn't be.

But we don't want all selected, we only need to move the camera and the lamp, so select both the camera and the lamp, by right clicking and holding shift.

Then type m to Move selected objects to a different layer. A pop up will appear wherever your mouse is, to select a different layer, merely click on one of the small grey boxes in the pop up.
Note that layers in Blender are really more like storage lockers or folders and not like layers in graphics.

The 3D View Header is a really useful collection of icons, operations and settings - a sort of command central for Blender operations and manipulations.

First you should notice that we are in Object Mode. Object mode allows us to deal with objects as objects, but not to edit their parts individually. We can move or scale or delete this whole cube, but we cannot do anything to just one of its faces or just one vertex for instance.

Next to it is an icon that shows what 'shading view' of our object we are looking at. The default starter view is solid. Have a look at some of the others, but for now plan to stay in solid view

You will find wireframe very useful in modeling, but since the shortcut for wireframe is so easy (z), I tend to ignore the icon alone and just press z when I want a wireframe view.  

Next to that is the Pivot Point. We will discuss and use and abuse the Pivot Point quite a bit in later project classes. For now just leave it as is.

Next to that is the control to display or turn off the 3D manipulator widget. I keep mine off mostly. You don't actually need it to move things around in Blender, the way you do in SL but if you find it makes things easier, then leave it on.

Under that is a 2-part Tooltip. Like many programs, if you hover over an icon, blender will pop up a little tool tip window telling you what that thing does. As a bonus, it also gives you the relevant commands to use in the Python scripting language in case you want to learn that and possibly become a Blender developer. Personally I mostly find the python stuff almost frightening, so I will show you where in preferences to turn that off if you want to. 

Look for preferences under File menu > User Preferences.

I suggest you think of Blender preferences as settings to try now and again for different projects. You might want to turn the number of undo steps down,
especially if you are on an older computer or a bit short on RAM. You definitely should allow yourself several hours to explore the possibilities in the Add Ons tab. Above are 2 optional settings, the first to turn off the Python scripting tips in tool tips, the second to turn down the number of undo steps.

I think that slide speaks for itself, though students regularly seem to balk at being told they must do something. Fear not, nothing will be overridden by having these on, you won't notice that your mouse or Numpad behaves as though you are not giving them credit or something.

Most people only ever see the default grey factory settings for Blender, since people who make tutorials seem to think you will want your interface to match the one in the tutorial exactly.

In case you want to match mine exactly for later classes, or maybe think grey on grey on grey is a bit depressing, check out some other Blender Theme presets.

mmm eye candy

To uncover all the color options shown, under the Themes tab, first choose a theme, then choose an editor or window from the list you would like to make adjustments for. In the slide I have selected the Ubuntu Ambience theme, then decided to see how things look in the 3D view. You can see that 3d view is selected because it is highlighted in purple.

The main thing I'll be worrying about is the background color of the 3d window. I think black is too dark and too reflective to stare at for hours at a time, and I like to have enough contrast with the floor grid and backing to be useful.
Figuring out which setting affects the bg took some poking, so I have circled it in orange in the image to the left. Look for "Gradient High/Off"

Another thing that really counts for seeing clearly in Blender is making sure that the text can be seen clearly. You will find this setting on the System tab, on a button called DPI:72 (what they were thinking on that one is beyond me). Anyway, press on the button and you can slide the text larger by moving your hand to the right, or smaller by going left. Much better! 

Now Save your new User Settings so that when you start Blender you will get an interface that feels a bit more like home. You can keep improving and changing the look of Blender as you spend more time in there. 

Some things to think about are making face dots or vertices larger, improving contrast between selected and unselected elements, making sure you can quickly and easily see whether a button is on  or off. As you make changes to the UI or your preferences, save them each time here.

Time to go back to the 3D view and see what our cube is up to.
Remember the 3 ways to select things (there are others, but this is plenty for now):

Right click, select from the list in the Outliner window and A to select All.

Select the cube. 

If you have already watched some Blender Tutorials, you will have heard the phrase,"Tab into edit mode" that's because pressing the Tab key will switch between the 2 main modes (usually Object & Edit), 

Things look different in Edit Mode. 

Also some new buttons have appeared on the header bar, because we can do things in Edit mode that we couldn't do in Object Mode.

We'll use these icons for a kind of crash course on the fundamental structure of mesh. Mesh is defined or created first of all by points or Vertices in 3D space, Edges run between 2 points, and Faces form the surfaces in between.

Blender like most 3D editing programs allow you to edit mesh at any of these 3 levels. A simpler way to put that is we can do stuff to edges, to verts and to faces. 

Right now according to the icons, I am in Vertex selection mode. But since every vertex of the cube is selected, the whole cube appears orange.

Type a to deselect All, then right click on a corner to select just one vertex.

Now you can pull just that vertex around and your cube will change shape as the edges and faces connected to that vertex also get dragged along.

If like me, you have turned your manipulator widget off, you might be wondering how to move this vertex or anything around. 

In Blender to move something you press G for Grab, then just move your hand/mouse. 

Now right click to select all 4 vertices on whichever side is facing you. 

Scale (to resize) is S.

Scale can seem a bit tricky. If you start with your hand back from the element your are resizing, you will find it easier to control. You can pull all the way back until the indicator arrows go off the screen and they will come in from the other direction. That is the continuous grab preference in action.

Since I like to point out Blender brilliance and especially its logic when and where I can, I usually encourage people to guess what the keyboard command to Rotate a face is. Since Grab is g, and Scale is s, in a perfect world, Rotate should be r, and it is! Happy dance.

Press A to deselect All. Now let's look at face selection mode.

You can use the buttons on the bottom Header to change selection modes, but you don't have to. You can just press Ctrl Tab to bring up a pop up menu to change Mesh Select Mode

Menus like this pop up wherever your mouse is when you call them, which makes for a very fast workflow.  

In face selection mode the view of our mesh changes slightly. Now we see little square dots on the faces of our mesh. In edge selection mode you won't see anything unless you right click to select an edge or two.

So you can manipulate mesh at the vertex, face and edge levels. Most basic operations work at each of these levels. In most projects in Blender you should plan to use different selection modes based different operations you are doing to your model. But for now, just get comfortable hitting Ctrl Tab to quickly change selection modes.

As important as learning how to make edits to things like cubes, is learning how to navigate around inside the 3D space. You need to be able to see what you are working on from all angles at all times quickly and easily. 

Typically in 3d applications, the object never actually moves and instead the modeler or sculptor is changing her view of the model as she works. This can become so fast and seamless that you may feel you are actually holding the object in your hands as you work on it. But that will only come with practise. It literally takes time to develop the muscle memories for how to navigate inside a 3D program. Think of it as similar to learning the moves in a video game. With enough repetition and some time you wioll eventually get the moves down so well, they will become second nature. Blender is like this, just don't expect a high score the first time you play.

If you have a scroll wheel on your mouse, that is what Blender means by the 3rd or Middle Mouse Button (MMB). Just press on it to treat it like a button instead of a wheel.

If you do not have a 3rd mouse button, good thing you turned on Emulate 3 Button Mouse in preferences, now you can use these substitute commands:

Ctrl Alt together to zoom in or out by moving your hand.

Alt key + left click to toggle or rotate your view.

Alt + Shift + left click to pan the view side to side or up and down.

Panning feels especially like you are picking up the object and moving it into position, but you're not, you are navigating or changing your view. 

By the way, I use a Graphics Pen & Tablet in Blender, and I love it. How to set that up if you have one is on an earlier blog post.

But best of all, and completely required for accurate building is how easy it is to snap to a particular view in Blender. This is where using the NumPad or just plain numbers since we turned on Emulate NumPad, will come in handy.

First off, note that there are 2 main ways of viewing 3D space. In the upper left corner of the 3d viewport you will see either User Persp or User Ortho. 

Perspective view in 3D applications is an attempt to make things look naturalistic by imitating the same kind of distortion we would see based on vanishing points. Orthographic views attempt to display objects without this distortion to give a more geometrically accurate representation of the model or scene. As a general rule, plan to work in orthographic view and maybe occasionally toggle over into perspective to see how things look.

Press 5 to switch to ortho.

Secondly there is apparently more than one entity determining the view. I am referring to the word "User" in User Ortho & User Persp. Blender is pointing out that YOU determined this view. You dragged some stuff around and zoomed all over the place and arbitrarily landed on some view or other and then just left it that way.
It doesn't have to stay this way. 

Press number 1.

Blender snaps to a Front view. Now press 3. Number 3 is to the right of 1 on the NumPad. Blender snaps to the right side view.

7 is on top of 1, pressing 7 will snap to a top view.

You can explore the other numbers to change your view in stepped increments, but knowing only these 3 will probably be enough. 

1 is front; 3 is right; 7 is top.

Adding Ctrl to these will show the opposite view. So ctrl 1 (front) is back. 

If you want to see things from the left side, since you know that right view is 3, then the opposite of this will be ctrl 3, and since you know top is 7, then the bottom view will be ctrl 7. 

How sweet is that?

These snap to views are extremely useful as constraints for operations such as extruding on only one axis. Used with the background grid the snapped ortho views are ideal for easily achieving precise alignments and sizes while you model mesh. You'll get to that as soon as you feel ready to start trying to model something. 

Last step and last shortcut for this introduction is how to get rid of the default cube and leave a nice clean scene to come back to. 

X to delete the default cube... or whatever weird shape you are now looking at.

You can see that x brings up a whole list of possibilities. Deleting vertices will wipe out the mesh entirely, which is what we want. You can experiment with what the others do and ways to make use of them later.

Lastly go to Front Ortho view by pressing 1, 5
and press  Ctrl U to save this empty space as your Start Up File, so next time you open Blender you have a nice clean scene to mess around in.

In closing some general advice - don't worry and try not to panic. You probably cannot actually break Blender, though it will crash now and again. Save often. You can get a new Blender anytime for free if you do somehow manage to break it.

Try not to think of this as a task to memorize shortcuts or menu locations. No one, (except maybe you) thinks that you just sit down and learn Blender the way you learn the contents of a brochure or study for a test. No one was born knowing how to model in 3D software. 

The best thing you can do is just make yourself comfortable in there, and the way to that is spend as much time as often as you can trying to use Blender to do simple little things. 

Go on, pretend it's a game that lets you make anything you can imagine. And have fun!

Here are some tuts & links & stuffs that I think are really good for total Blender beginners, collected on a Pinterest page for easy access. 

Other things I think I should mention:

Expect to have to watch most videos several times, pause as often as you like, make notes or whatever. I mention this because I have noticed that the same people who seem to think that they will learn a program and then make something with it, seem to also think they will watch a video and then know how to do whatever was demonstrated in the video. 

Maybe it's me, but I think that's being a bit unrealistic. Seeing may be believing, but it is not knowing, and definitely not knowing how to do something. If you watched a video of someone playing saxophone, would you expect to open up your new shiny sax and belt out a tune? 

Not likely. 

As I said, it will take time for Blender to soak in. You will learn the commands and how to navigate gradually simply from using the program. Eventually these bits and pieces of info will become muscle memories, and Blender will become a fabulously flexible (and fast!) modeling tool that you can manipulate at will. 

All the best,