Essential Blender- P1

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Essential Blender- P1

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Essential Blender- P1: You may copy and distribute exact replicas of the OpenContent (OC) as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice and disclaimer of warranty; keep intact all the notices that refer to this License and to the absence of any warranty; and give any other recipients of the OC a copy of this License along with the OC.

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  1. License All the chapters in Essential Blender have been released under the Blender Open Content License, which can be read below. BLENDER OPEN CONTENT LICENSE Terms and Conditions for Copying, Distributing, and Modifying Items other than copying, distributing, and modifying the Content with which this license was distributed (such as using, etc.) are outside the scope of this license. 1. You may copy and distribute exact replicas of the OpenContent (OC) as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice and disclaimer of warranty; keep intact all the notices that refer to this License and to the absence of any warranty; and give any other recipients of the OC a copy of this License along with the OC. You may at your option charge a fee for the media and/or handling involved in creating a unique copy of the OC for use offline, you may at your option offer instructional support for the OC in exchange for a fee, or you may at your option offer warranty in exchange for a fee. You may not charge a fee for the OC itself. You may not charge a fee for the sole service of providing access to and/or use of the OC via a network (e.g. the Internet), whether it be via the world wide web, FTP, or any other method. 2. You may modify your copy or copies of the Open Content or any portion of it, thus forming works based on the Content, and distribute such modifications or work under the terms of Section 1 above, provided that you also meet all of these conditions: a. You must cause the modified content to carry prominent notices stating that you changed it, the exact nature and content of the changes, and the date of any change. b. You must cause any work that you distribute or publish, that in whole or in part contains or is derived from the OC or any part thereof, to be licensed as a whole at no charge to all third parties under the terms of this License, unless otherwise permitted under applicable Fair Use law. c. The name of the Copyright Holder or contributors to the OC may not be used to endorse or promote products derived from this software without specific prior written permission. These requirements apply to the modified work as a whole. If identifiable sections of that work are not derived from the OC, and can be reasonably considered independent and separate works in themselves, then this License, and its terms, do not apply to those sections when you distribute them as separate works. But when you distribute the same sections as part of a whole which is a work based on the OC, the distribution of the whole must be on the terms of this License, whose permissions for other licensees extend to the entire whole, and thus to each and every part regardless of who wrote it. Exceptions are made to this requirement to release modified works free of charge under this license only in compliance with Fair Use law where applicable.
  2. 3. You are not required to accept this License, since you have not signed it. However, nothing else grants you permission to copy, distribute or modify the OC. These actions are prohibited by law if you do not accept this License. Therefore, by distributing or translating the OC, or by deriving works herefrom, you indicate your acceptance of this License to do so, and all its terms and conditions for copying, distributing or translating the OC. NO WARRANTY 4. BECAUSE THE OPENCONTENT (OC) IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE OC, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE OC "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK OF USE OF THE OC IS WITH YOU. SHOULD THE OC PROVE FAULTY, INACCURATE, OR OTHERWISE UNACCEPTABLE YOU ASSUME THE COST OF ALL NECESSARY REPAIR OR CORRECTION. 5. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MIRROR AND/OR REDISTRIBUTE THE OC AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE OC, EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
  3. C hapter 1: A n Introduction to 3D A rt By Roland Hess If you are completely unversed in 3D art, then this introduction is for you. If you already know what you're doing and are just using this book to get yourself up to speed with Blender, then skip right on to Chapter 2, The Blender Interface. (Of course, if you did that you would miss out on a fantastic analogy for 3D art that might give you inspiration some day when your mouse just doesn't want to do its thing and all you can think of are chrome spheres and checkerboard planes.) Please note that the screen shots and references to Blender in this chapter are not tutorials - they are simply general examples of what can be done. You won't find step-by-step instructions on how to recreate them. We'll get to all that later. T aking Pictures of T iny L ittle Houses 3D Art is little more than building a model and taking a picture of it. Image:Dummy.png Figure 1.1: A street scene created with miniatures and raw materials. Did you ever build a little setup with toy houses, put miniature figures in it, maybe snap off twigs and bits of bushes and stick them in clay to look like little shrubs? Did you take a picture of it, close enough to the ground to try to make it look like the town was real? Did you spend countless hours in your room as a kid trying to make the whole thing as realistic as possible, while all the other kids taunted you and called you the "Hermit King?" Okay, maybe that was just me. But that, minus the taunting, is the essence of 3D art. Creating and taking pictures of models. Admittedly, 3D Art is a much deeper topic than that, but that is where we'll start. Raw M aterials If you were going to build a diorama of a downtown street, what would you need? Boxes, for the buildings. A knife or scissors to cut windows and doors, or maybe just a marker to draw them on, depending on how fancy you want to get. Colored paper and odd bits of cardboard to make things like the road, the sidewalks and curbs, the trash bins and benches. Maybe if you were feeling lazy, you'd just buy a couple of miniature benches and street signs from a hobby shop. If you were feeling especially clever, you might make a mixture of glue and colored sand to simulate roofing material. You'd need a couple of clippings from live plants to stick around as trees and bushes. Image:Dummy.png Figure 1.2: Some of the raw materials you would use to build a diorama. If you had all of that, you could build yourself a nice little street scene.
  4. When it was built, and it looked the way you wanted, you could set a digital camera on the ground, frame up the picture in the viewfinder and snap away. You could move the camera to get shots from different angles. If you really wanted to, and you had built things properly, you could have some action figures taped to sticks running around the place while one of your friends recorded it with her nice digital video camera. Working in computer generated 3D art is almost exactly like this, except that you don't risk slicing the end off your finger with an artist's knife. First, you build your model. Then, you paint it. Then you arrange all your models where you want them and start snapping pictures. Building Models In 3D art (commonly referred to as CG - Computer Graphics, CGI - CG Imaging, or simply 3D) almost all models are built from triangles. It may not seem so at first, because many modeling tools let you work with quadrangles, curves, bevels, mathematical surfaces and a bunch of other stuff I'm not even going to mention. But in the end, it's all triangles. Why, you might wonder? Remember all the times that you've smacked your computer and said "stupid machine"? Well, you were right. Figure 1.3: This is a triangle. Computers are stupid. Way down in their guts, all they understand are triangles, so that's what you're stuck with. Fortunately, computers are really good at calculating and drawing triangles, and there are a lot of very smart people out there (like the people who wrote and maintain Blender) who know how to build tools that make it so easy for you to work with triangles that you often don't even realize that's what you're doing. And so, from triangles, you will see that you can build a quadrangle.
  5. Figure 1.4: These are quadrangles. With triangles and quadrangles (quads, for short), you can build anything you like. A box for a diorama street scene. A monkey. Something beautiful. Figure 1.5.1: A simple 3D model, showing its triangle construction on the right.
  6. Figure 1.5.2: A monkey head (Suzanne, Blender's mascot), showing triangles. Figure 1.5.3: Detail of "Miracle" by Robert J. Tiess. The tools that have been developed to help you work with triangles let you move their corners, their edges or the whole thing at once. They let you duplicate them, smooth the angles between them, split them apart and weld them together. They let you push them around like clay, order them in rows or rotate them in space around an arbitrary axis. Let's take a look at some of the shortcuts and tools that are available to you when building 3D models. (The following is not a tutorial, so we don't recommend trying to do this yet. It's just a sample of the kinds of things you can do.) Modeling Tools
  7. In Blender, as in all 3D graphics applications, you have access to a number of different very basic models to help get you started. Figure 1.6.1: The primitive shapes accessible through the toolbox. Figure 1.6.2: Some of the available primitive shapes. From this beginning, you can use the other tools to grow, shape and refine your model. If, for example, you wanted to take that cube and build a 3D plus symbol out of it, you could use one of the most popular modeling tools available: the Extrude tool.
  8. Figure 1.7.1: A standard cube, with the top face selected.
  9. Figure 1.7.2: The top face, extruded upward.
  10. Figure 1.7.3: Two of the sides and the bottom face selected.
  11. Figure 1.7.4: Those faces extruded, to form a plus (+) symbol. Now, you might want to change the shape of the plus symbol, making each arm grow in the middle. To do something like this, you would use another popular tool: the Loop Cut tool.
  12. Figure 1.8.1: Loop Cut tool in use on the top arm.
  13. Figure 1.8.2: Loop Cut made around the center of each arm.
  14. Figure 1.8.3: End and center faces scaled down to make a nice new shape. In the last illustration, you shrunk (scaled down) the quads on the ends of the plus, and the ones that made up the center, giving you a nice new shape. Now, you might think the edges are too sharp, so you use a combination of the bevel tool and the smooth tool until your model looks like this:
  15. Figure 1.9: A beveled, smoothed plus symbol. Okay, you might be thinking, I only see a few triangles there.
  16. Figure 1.10: The plus symbol with triangles made visible. Ah. There they are. Blender, like most 3D packages, offers you dozens of modeling tools that you can combine in an almost infinite variety to produce any kind of model you can imagine. Try doing that with a cardboard box. M aterials Let's go back to your little cardboard box model of the street. If you just stick a bunch of plain boxes in a row, it's not going to give a very good illusion of a street. To make it better, you need to make the boxes look more realistic. Let's say that you want the Post Office to look like it's made of brick. You have some options: 1. draw bricks directly on the box with markers or paints; 2. find a picture of a brick wall, cut it out and glue it to the box; 3. make an
  17. actual brick-like surface out of glue and red sand, apply it to the box, and painstakingly carve the mortar lines into it. Of course, to do a good job, you'd have to finish the rest of the box. Paint trim around the door and window holes. Maybe cut and fasten rectangles of clear plastic to make windows. Come up with something neat for the shingles. For a nice little detail, you can draw a little sign on the door that displays the office hours. So, how does this translate to 3D? In 3D, you define and apply different materials to your models, just like you would for your diorama. In Computer Graphics, you can get your materials in a variety of ways. First, you must tell the computer what kind of properties you want your material to have: should it be shiny or dull? Rough or smooth? How should it react to light hitting it from different angles? All of these questions are answered by using different Shaders. In Blender, you can choose from a variety of shading models, each suited to slightly different tasks. Figure 1.11.1: Ball with Lambert shading. Basic shading model.
  18. Figure 1.11.2: Ball with Oren-Nayer shading. Good for rough surfaces.
  19. Figure 1.11.3: Ball with Minnaert shading. Good for velvets and cloths.
  20. Figure 1.11.4: Ball with Toon shading. Simulates cartoon-style coloring. Once you've chosen the basic properties for your material, you move on to defining things like colors. If you just want the whole thing to be a uniform color, it's pretty simple. If you want to get more complex, though, say, to make your material look like bricks for example, you need to add Textures. And just like texturing a diorama, there a number of ways you can obtain digital textures. You could use a digital photograph of a brick wall. You could use Blender's texture generation tools to make a simulation of brick. You could use Blender's 3D painting tools to paint bricks directly onto the surface.
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