HowTo:Bevel - Revision history

Augie.ben.doggie: /* Introduction */ fixed a link

2013-01-05T22:18:07Z

‎Introduction: fixed a link

Nikai: /* Typical beveling and flat/curved combo cases */ sp

2010-06-22T20:53:48Z

‎Typical beveling and flat/curved combo cases: sp

AzureSky: Added categories

2008-09-09T15:20:11Z

Added categories

empatiico: /* Introduction */

2008-06-13T05:35:21Z

‎Introduction

chuck_starchaser: /* Typical beveling and flat/curved combo cases */

2007-02-23T19:56:44Z

‎Typical beveling and flat/curved combo cases

chuck_starchaser: /* Typical beveling and flat/curved combo cases */

2007-02-07T13:45:32Z

‎Typical beveling and flat/curved combo cases

chuck_starchaser: /* Typical beveling and flat/curved combo cases */

2007-02-07T13:44:13Z

‎Typical beveling and flat/curved combo cases

chuck_starchaser: /* In more detail */

2007-02-07T13:41:09Z

‎In more detail

chuck_starchaser: /* Introduction */

2007-02-07T13:34:48Z

‎Introduction

chuck_starchaser: /* Introduction */

2007-02-07T13:34:05Z

‎Introduction

@@ Line 1: / Line 1: @@
 ===Introduction===
-This tutorial, out of necessity, is a bit of a mix of topics. Make sure you read the [http://vegastrike.sourceforge.net/wiki/HowTo:Smooth_Groups smoothing groups] tutorial first, though.
+This tutorial, out of necessity, is a bit of a mix of topics. Make sure you read the [[HowTo:Smooth_Groups|smoothing groups]] tutorial first, though.
 Some of the instructions are Blender-specific hotkeys, but the main idea applies no matter what tools you use.

@@ Line 73: / Line 73: @@
 Much better; isn't it?
-What happened is that when we made that middle cut, we caused new vertex normals to appear. Vertex normals are generated by averaging the vertex's neigboring face normals. The neigboring faces of those vertexes formed by the middle cut are parallel and slanted, so the new normals are at the exact angle we wanted at the middle of the bevel.
+What happened is that when we made that middle cut, we caused new vertex normals to appear. Vertex normals are generated by averaging the vertex's neighboring face normals. The neighboring faces of those vertexes formed by the middle cut are parallel and slanted, so the new normals are at the exact angle we wanted at the middle of the bevel.
 It's still not perfect, though; as the flat faces on the sides still don't look flat. To fix that, we add two more cuts:

← Older revision		Revision as of 15:20, 9 September 2008
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	--chuck_starchaser		--chuck_starchaser
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		+	[[Category:HowTos\|Bevel]]
		+	[[Category:Modeling\|Bevel]]
		+	[[Category:Blender\|Bevel]]

@@ Line 1: / Line 1: @@
 ===Introduction===
-This tutorial, out of necessity, is a bit of a mix of topics. Make sure you read the smoothing groups tutorial first, though.
+This tutorial, out of necessity, is a bit of a mix of topics. Make sure you read the [http://vegastrike.sourceforge.net/wiki/HowTo:Smooth_Groups smoothing groups] tutorial first, though.
 Some of the instructions are Blender-specific hotkeys, but the main idea applies no matter what tools you use.

@@ Line 71: / Line 71: @@
-What happened is that when we made that middle cut, we cause new normals. Vertex normals are generated by averaging the vertex's neigboring face normals. The neigboring faces of those vertexes formed by the middle cut are parallel and slanted, so the new normals are at the angle we wanted.
+Much better; isn't it?
 It's still not perfect, though; as the flat faces on the sides still don't look flat. To fix that, we add two more cuts:
@@ Line 101: / Line 104: @@
 My lighting setup is less than ideal, but you get my drift.
 ===Actual model example===

← Older revision		Revision as of 13:45, 7 February 2007
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−	What happened is that when we made that middle cut, we cause new normals. Vertex normals are generated by averaging the vertex's neigboring face normals. The neigboring faces of those vertexes formed by the middle cut are parallel and slanted, so the new normals are at the ~~right~~ angle we wanted.	+	What happened is that when we made that middle cut, we cause new normals. Vertex normals are generated by averaging the vertex's neigboring face normals. The neigboring faces of those vertexes formed by the middle cut are parallel and slanted, so the new normals are at the angle we wanted.
	It's still not perfect, though; as the flat faces on the sides still don't look flat. To fix that, we add two more cuts:		It's still not perfect, though; as the flat faces on the sides still don't look flat. To fix that, we add two more cuts:

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-What's happening is that the videocard interpolates, --across entire surfaces--, the vertex normals at the edges. In the case on the left, the small, slanted strip in the middle gets "flat-shaded", because the normals at either side of it are parallel!!! And the bigger surfaces to the left and right, which we intended to look flat, are actually shaded across, because the normals at the edges are NOT parallel, and so get interpolated across. The beveled corner on the right gets smooth shaded properly, as its normas at either side are at right angles; but the big flat surfaces connecting to it look rounded, which wasn't our intention :-/
+What's happening is that the vertex normals are computed by averaging the face normals connected to that vertex. Then the videocard interpolates, --across entire surfaces--, the vertex normals at the edges.
 What to do?
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 My lighting setup is less than ideal, but you get my drift.
 ===Actual model example===

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 b) How to split smooth groups:
 Start by smooth-shading: In Blender, press A to select all faces, W->Set Smooth. Now, surfaces at an angle should look really weird...
-A again to un-select everything. Now select all faces (manually) that should be part of a continuum without sharp edges, press Y, for split, and answer 'yes'. Bingo! This should be done for all continuous surfaces, no matter whether they are curvy or flat, so as to avoid the multiplication of vertices in the gpu.
+Press A again to un-select everything. Now select all faces (manually) that should be part of a continuum without sharp edges within, but with a sharp boundary; press Y, for split, and answer 'yes'. Bingo! This should be done for all continuous surfaces, no matter whether they are curvy or flat, so as to avoid the multiplication of vertices in the gpu.
-Check out the SES model, for example: Select any face and press Ctrl-L to see the extents of the split group it belongs to. Here's the current file:
+Check out the SES model, for example: Select any face and press Ctrl-L to see the extents of the split group it belongs to. Here's the current (as of this writing) file:
 http://deeplayer.com/dan_w/NewMod/SES/fullbody14.blend
 Back to a) for a moment: You might wonder, then: when should one use flat shading? Primarily for any single-poly surface. Small cube boxes, for example, you'd gain nothing from flat-shading and splitting the sides, because you'd be generating as many vertices, manually, as the gpu would generate, anyhow. Any surface that's more than a single quad, though, should be flat-shaded. In the SES, for example, if you look at the buildings on top of the military section, some of them have an L shape; they have a smooth-shaded and split roof; with flat-shaded, non-spit sides --since the sides are a single quad each.
-c) The artifacts of smooth-shading ....
+c) The artifacts of smooth-shading (and here we tackle beveling, the subject of the title of this tutorial) ...
 You have to understand how smooth-shading normals are generated, and how they affect the way polygons are shaded.
 First of all, the face normals Blender shows you are only good for flat-shaded surfaces. Smooth-shaded surfaces work on the basis of vertex normals. You want to show those, instead, to understand smooth shading phenomena.

@@ Line 10: / Line 10: @@
 b) You can achieve a flat-shaded look while actually using smooth shading, by "spitting the smooth groups". This doubles (splits) the vertices at the edges of each smooth groups surface, slightly increasing your vertex count in the mesh file; but it is much less costly, in real vertex count processed in the gpu, than flat-shading the whole surface.
-c) In smooth shading, the video card interpolates normals, and this may cause unwanted effects; but the unwanted effects can be solved with extra cuts, which, again, add a bit to the geometry in the file, but cost far less than flat-shading, over all.
+c) In smooth shading, the video card interpolates normals, and this may cause unwanted effects; but the unwanted effects can be solved with extra cuts, which, again, add a bit to the geometry in the file, but cost far less (in real performance) than flat-shading.
 ===In more detail===

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 a) Flat-shading more than doubles the amount of vertices to process in the gpu (videocard). It does not mean that you should "never" use flat-shading, but it does mean you need to think about where and when to use it. The multiplication of vertex data occurs in the video card (GPU), not in the file, so you may think you have a low poly count, and feel falsely reassured; but the vertex count that is actually processed may be astronomical, if you flat-shade everything. Essentially, each tri will have its own 3 vertices!... no sharing at all!!!
-b) You can achieve flat-shaded look while actually using smooth shading, by "spitting the smooth groups". This doubles the vertices at the edges of each smooth groups surface, increasing your vertex count in the mesh file; but it is much less costly than flat-shading the whole surface.
+b) You can achieve a flat-shaded look while actually using smooth shading, by "spitting the smooth groups". This doubles (splits) the vertices at the edges of each smooth groups surface, slightly increasing your vertex count in the mesh file; but it is much less costly, in real vertex count processed in the gpu, than flat-shading the whole surface.
-c) In smooth shading, the video card interpolates normals, and this may cause unwanted effects; but the unwanted effects can be solved with extra cuts, which add to the geometry, but cost far less than flat-shading, over all.
+c) In smooth shading, the video card interpolates normals, and this may cause unwanted effects; but the unwanted effects can be solved with extra cuts, which, again, add a bit to the geometry in the file, but cost far less than flat-shading, over all.
 ===In more detail===