Difference between revisions of "Bump map"

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(Added additional information about bumpmaps on decals in CSGO)
 
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[[Image:Example of bump mapping.jpg|thumb|200px|The above material in-game.]]
 
[[Image:Example of bump mapping.jpg|thumb|200px|The above material in-game.]]
  
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Textures often called '''Bump Maps''', or '''Normal Maps''' are used to simulate three-dimensional details on a two-dimensional surface by manipulating its lighting. The process is known as [[Wikipedia:Normal mapping|Normal Mapping]].  
+
Textures often called '''Bump Maps''', or '''Normal Maps''' are used to simulate three-dimensional details on a two-dimensional surface by manipulating its lighting.
 +
 
 +
{{note|Static props using bump maps can not be lit per-vertex, except in {{csgo}}.}}
 +
{{note|Bump maps cannot be used on decal textures, except in {{csgo}}. In order for these to function properly, the surface that they are placed on must also have a bumpmap.}}
  
 
== Format ==
 
== Format ==
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:* 255 = down
 
:* 255 = down
 
; Blue
 
; Blue
−
: Height (Z axis). Valve's "flat" bump map textures use 248.
+
: Height (Z axis).
 
:* 0 = facing 'in' to the texture, away from the viewer. This is a 'bad' value. Anything under 128 means that the surface should be facing away from the player, which is not possible.
 
:* 0 = facing 'in' to the texture, away from the viewer. This is a 'bad' value. Anything under 128 means that the surface should be facing away from the player, which is not possible.
 
:* 128 = maximum depth capable of receiving dynamic light. It's a bad idea to go under this.
 
:* 128 = maximum depth capable of receiving dynamic light. It's a bad idea to go under this.
 
:* 255 = facing 'out' of the texture towards the viewer.
 
:* 255 = facing 'out' of the texture towards the viewer.
 +
 +
 +
{{note|A flat bump map should be [128, 128, 255]. <code>dev/flat_normal</code> is a flat bump map present in every game.}}
  
 
The three channels represent a normal vector for every pixel which represents the direction that the pixel is facing in 3D space. This allows the engine to generate shadows and highlights on a two-dimensional surface, or give a 3D model more detail.
 
The three channels represent a normal vector for every pixel which represents the direction that the pixel is facing in 3D space. This allows the engine to generate shadows and highlights on a two-dimensional surface, or give a 3D model more detail.
  
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A bump map is largely useless for really flat surfaces like smooth concrete or metal, but even rough concrete sometimes has enough depth to it to make one worthwhile.
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A bump map is largely useless for really flat surfaces like smooth concrete or metal, but even smooth concrete sometimes has enough depth to it to make one worthwhile.
  
 
[[file:normalmap.gif]]
 
[[file:normalmap.gif]]
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== Creation ==
 
== Creation ==
  
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A bump map should:
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A bump map should be rendered in Tangent space and use vector directions X+ Y- Z+.
−
 
 
−
*Be at the same resolution as the [[albedo]]/s it is to be used with.
 
−
*Be stored in an uncompressed format (see [[#Conversion|Conversion]]). Note that valve saves all of their normals/bumpmaps in a compressed format, uncompressed formats should only be used when strong artifacts occur or becomes extremely noticeable!
 
−
*Be rendered in Tangent space.
 
−
*'''Use vector directions X+ Y- Z+'''.
 
  
−
{{note|The green channel may need to be inverted depending on the software used to create it.}}
+
{{note|There are basically two sets of rules for normal maps: [[DirectX]] and [[OpenGL]]. Their interpretation of green channels are opposite. [[Source]] takes the former. Thus, the green channel may need to be inverted depending on the software used to create it. }}
  
 
=== Programs ===
 
=== Programs ===
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;2D
 
;2D
 
:[[Normal Map Creation in Photoshop or Paint Shop Pro|Photoshop or Paint Shop Pro]]
 
:[[Normal Map Creation in Photoshop or Paint Shop Pro|Photoshop or Paint Shop Pro]]
 +
:[http://www.youtube.com/watch?v=WsFe-E-33IQ Substance Designer]
 
:[[Normal Map Creation in The GIMP|The GIMP]]
 
:[[Normal Map Creation in The GIMP|The GIMP]]
 +
:[http://www.youtube.com/watch?v=xDZDWvTUz-c nDo]
 
;3D
 
;3D
 
:[[Normal Map Creation in XSI|XSI]]
 
:[[Normal Map Creation in XSI|XSI]]
−
:[[Normal Map Creation in ZBrush2|ZBrush2]]
+
:[[Normal Map Creation in ZBrush|ZBrush]]
 
:[[Normal Map Creation in Lightwave|Lightwave]]
 
:[[Normal Map Creation in Lightwave|Lightwave]]
−
:[[Normal Map Creation in 3D Studio Max|3D Studio Max]]
+
:[[Normal Map Creation in 3ds Max|3ds Max]]
 
:[[Normal Map Creation in Maya|Maya]]
 
:[[Normal Map Creation in Maya|Maya]]
 
:[[Normal Map Creation in Blender|Blender]]
 
:[[Normal Map Creation in Blender|Blender]]
−
:[http://developer.nvidia.com/object/melody_home.html NVIDIA Melody]
+
:[http://www.nvidia.com/object/melody_home.html NVIDIA Melody]
 
:[http://planetpixelemporium.com/tutorialpages/normal2.html Cinema 4D]
 
:[http://planetpixelemporium.com/tutorialpages/normal2.html Cinema 4D]
 
:[[NormalMapper]]
 
:[[NormalMapper]]
 
:[http://xnormal.net/ xNormal]
 
:[http://xnormal.net/ xNormal]
 
;Other
 
;Other
 +
:[http://store.steampowered.com/app/325910/ Bitmap2Material 3]: Alternative to CrazyBump.
 
:[http://www.crazybump.com CrazyBump]: Produces some very good normal maps. Some of them can be argued as almost having the same depth as a parallax map.
 
:[http://www.crazybump.com CrazyBump]: Produces some very good normal maps. Some of them can be argued as almost having the same depth as a parallax map.
 
:[http://filterforge.com/filters/8774.html Filter Forge]: Can generate normal maps for its filters and external images.
 
:[http://filterforge.com/filters/8774.html Filter Forge]: Can generate normal maps for its filters and external images.
 +
:[https://sites.google.com/site/ccdsurgeon/download/ InsaneBump]: Specifically made to be a free alternative to CrazyBump, produces high quality normal maps.
 
:[http://mindtex.com MindTex]: A cheaper alternative to CrazyBump. Also produces high-quality normal maps.
 
:[http://mindtex.com MindTex]: A cheaper alternative to CrazyBump. Also produces high-quality normal maps.
 +
:[[Normal2dudv]]: a third party tool for converting bump maps to Dx8-friendly [[du/dv maps]].
 
:[http://shadermap.renderingsystems.com/ ShaderMap]: A free alternative to CrazyBump.
 
:[http://shadermap.renderingsystems.com/ ShaderMap]: A free alternative to CrazyBump.
 
:[https://sourceforge.net/projects/ssbumpgenerator/ SSBump Generator 5.3]: Another free, open source alternative to CrazyBump that generates Self Shadowed Bump Maps as well as normal maps.
 
:[https://sourceforge.net/projects/ssbumpgenerator/ SSBump Generator 5.3]: Another free, open source alternative to CrazyBump that generates Self Shadowed Bump Maps as well as normal maps.
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:[[Normal2dudv]]: a third party tool for converting bump maps to Dx8-friendly [[du/dv maps]].
 
  
 
=== Conversion ===
 
=== Conversion ===
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When converting your texture:
 
When converting your texture:
  
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# Choose BGR8888 or BGRA8888 (if your texture has an alpha channel) as your image format.{{tip|You can ''sometimes'' get away with DXT compression. More specifically, normal maps with DXT compression do not work in the Ep1 engine. They do however work in the later versions of the Source engine.}}
+
# Choose your image format. Uncompressed formats like BGR888 are higher-quality than compressed formats like DXT1, but be wary of file size.
 
# Check the "Normal map" box in the texture's flags list after the import is complete. It's about 1/5 of the way down the list.
 
# Check the "Normal map" box in the texture's flags list after the import is complete. It's about 1/5 of the way down the list.
  
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==== In [[Vtex]] ====
 
==== In [[Vtex]] ====
  
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# Save your normal map as a [[TGA]] in the same resolution as the original texture. Give it a name that ends in ''_normal''. The ''_normal'' at the end of the name will affect how [[Vtex]] converts it. For the brick wall example, we would name the file <code>brickwall_normal.tga</code>.
+
# Save your normal map as a [[TGA]]. Give it a name that ends in ''_normal''. The ''_normal'' at the end of the name will affect how [[Vtex]] converts it. For the brick wall example, we would name the file <code>brickwall_normal.tga</code>.
 
# Add <code>nocompress 1</code> and <code>normal 1</code> to <texture filename>.txt in the same folder as your texture, then compile.
 
# Add <code>nocompress 1</code> and <code>normal 1</code> to <texture filename>.txt in the same folder as your texture, then compile.
  
 
=== Implementation ===
 
=== Implementation ===
  
−
See <code>[[$bumpmap]]</code>.
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See {{ent|$bumpmap}}.
  
 
==See also==
 
==See also==
  
−
*<code>[[$ssbump]]</code>: creation and usage of Valve's new self-shadowing bump maps.
+
*{{ent|$ssbump}}: creation and usage of Valve's new self-shadowing bump maps.
−
*[http://planetpixelemporium.com/tutorialpages/normal.html An old article that explains normal mapping quite well.]
+
*[http://planetpixelemporium.com/tutorialpages/normal.html An old article that explains normal mapping quite well]
−
*[[Material Creation]]
+
*[http://wiki.polycount.com/wiki/Normal_map Polycount wiki page about normal maps]
−
*[http://www.cgtextures.com/content.php?action=tutorial&name=normalmap]
+
*[[Creating a Material]]
  
 
[[Category:Material System]]
 
[[Category:Material System]]
 
[[Category:Glossary]]
 
[[Category:Glossary]]
 
[[Category:Tutorials]]
 
[[Category:Tutorials]]

Latest revision as of 19:32, 16 April 2020

Français
A material's albedo (left) compared to its bump map.
The above material in-game.

Textures often called Bump Maps, or Normal Maps are used to simulate three-dimensional details on a two-dimensional surface by manipulating its lighting.

Note.png Note: Static props using bump maps can not be lit per-vertex, except in <Counter-Strike: Global Offensive>.
Note.png Note: Bump maps cannot be used on decal textures, except in <Counter-Strike: Global Offensive>. In order for these to function properly, the surface that they are placed on must also have a bumpmap.

Format

Each pixel in a bump map contains the (x, y, z) coordinates that define a normalized vector.

Because of this each color channel in a bump map has a meaning:

Red
Horizontal facing (X axis)
  • 0 = left
  • 128 = forward, or facing viewer
  • 255 = right
Green
Vertical facing (Y axis)
  • 0 = up
  • 128 = forward, or facing viewer
  • 255 = down
Blue
Height (Z axis).
  • 0 = facing 'in' to the texture, away from the viewer. This is a 'bad' value. Anything under 128 means that the surface should be facing away from the player, which is not possible.
  • 128 = maximum depth capable of receiving dynamic light. It's a bad idea to go under this.
  • 255 = facing 'out' of the texture towards the viewer.


Note.png Note: A flat bump map should be [128, 128, 255]. dev/flat_normal is a flat bump map present in every game.

The three channels represent a normal vector for every pixel which represents the direction that the pixel is facing in 3D space. This allows the engine to generate shadows and highlights on a two-dimensional surface, or give a 3D model more detail.

A bump map is largely useless for really flat surfaces like smooth concrete or metal, but even smooth concrete sometimes has enough depth to it to make one worthwhile.

Normalmap.gif

Creation

A bump map should be rendered in Tangent space and use vector directions X+ Y- Z+.

Note.png Note: There are basically two sets of rules for normal maps: DirectX and OpenGL. Their interpretation of green channels are opposite. Source takes the former. Thus, the green channel may need to be inverted depending on the software used to create it.

Programs

Bump maps as created by various programs.

Various programs can automate the creation of bump maps, either by image analysis or by using 3D geometry the user provides.

2D
Photoshop or Paint Shop Pro
Substance Designer
The GIMP
nDo
3D
XSI
ZBrush
Lightwave
3ds Max
Maya
Blender
NVIDIA Melody
Cinema 4D
NormalMapper
xNormal
Other
Bitmap2Material 3: Alternative to CrazyBump.
CrazyBump: Produces some very good normal maps. Some of them can be argued as almost having the same depth as a parallax map.
Filter Forge: Can generate normal maps for its filters and external images.
InsaneBump: Specifically made to be a free alternative to CrazyBump, produces high quality normal maps.
MindTex: A cheaper alternative to CrazyBump. Also produces high-quality normal maps.
Normal2dudv: a third party tool for converting bump maps to Dx8-friendly du/dv maps.
ShaderMap: A free alternative to CrazyBump.
SSBump Generator 5.3: Another free, open source alternative to CrazyBump that generates Self Shadowed Bump Maps as well as normal maps.

Conversion

In VTFEdit

When converting your texture:

  1. Choose your image format. Uncompressed formats like BGR888 are higher-quality than compressed formats like DXT1, but be wary of file size.
  2. Check the "Normal map" box in the texture's flags list after the import is complete. It's about 1/5 of the way down the list.
Tip.png Tip: VTFEdit can automatically generate bump maps. See the bottom-right of the import screen.

In Vtex

  1. Save your normal map as a TGA. Give it a name that ends in _normal. The _normal at the end of the name will affect how Vtex converts it. For the brick wall example, we would name the file brickwall_normal.tga.
  2. Add nocompress 1 and normal 1 to <texture filename>.txt in the same folder as your texture, then compile.

Implementation

See $bumpmap.

See also

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