SoTextureUnit Class Reference
[Textures]

Node that specifies the current texture unit and the associated mapping method. More...

#include <Inventor/nodes/SoTextureUnit.h>

Inheritance diagram for SoTextureUnit:

List of all members.

Public Types
enum	MappingMethod {   BUMP_MAPPING = SoTextureUnitElement::BUMP_MAPPING,   IMAGE_MAPPING = SoTextureUnitElement::IMAGE_MAPPING }
Public Member Functions
virtual SoType	getTypeId () const
	SoTextureUnit ()
Static Public Member Functions
static SoType	getClassTypeId ()
static unsigned int	getMaxTextureUnit (SoState *state=NULL)
Public Attributes
SoSFUInt32	unit
SoSFEnum	mappingMethod

---

Detailed Description

Node that specifies the current texture unit and the associated mapping method.

This node specifies the current texture unit for all subsequent 2D and 3D texture nodes (for example, SoTexture2, SoTexture2Transform, SoTextureCoordinate2, SoTextureCoordinateBinding, and SoTextureCoordinateFunction).

If the graphics board supports multitexturing (OpenGL 1.5 or GL_ARB_multitexture extension), then multiple textures, each defined by a texture unit, can be applied to the same shape. The maximum number of texture units depends on the board and can be queried using getMaxTextureUnit.

Multitexturing is supported by the following shapes:

• SoCone
• SoCube
• SoCylinder
• SoFaceSet
• SoIndexedFaceSet
• SoIndexedQuadMesh
• SoIndexedTriangleStripSet
• SoQuadMesh
• SoSphere
• SoTriangleStripSet

Each texture unit is defined by the following texture properties:

• image of the texture (derived from SoTexture)
• texture coordinates (SoTextureCoordinate2, SoTextureCoordinate3, SoTextureCoordinateBinding, etc.)
• automatic texture coordinates generation (derived from SoTextureCoordinateFunction)
• stack of matrix transforms (SoTexture2Transform, SoTexture3Transform, SoMatrixTransform, etc.)
• mapping method: image mapping or bump mapping.

Limitations:

• Multitexturing is not supported for non convex shapes (SoShapeHints::UNKNOWN_FACE_TYPE).

• Automatic texture coordinate generation (SoTextureCoordinateFunction) is not possible for the bump mapping method.

• When not using shaders, only units 0 to 3 can be used.

• When using shaders, texture unit properties (listed above) can be defined for units 0 to 7. When shaders are used, it is also possible to use SoVertexShaderParameter to specify texture coordinates to be used by the shader(s). SoVertexShaderParameter parameter sets are limited to 32 on OpenGL3 hardware.

FILE FORMAT/DEFAULT

TextureUnit {

unit	0
mappingMethod	IMAGE_MAPPING

}

ACTION BEHAVIOR

SoGLRenderAction, SoCallbackAction
Sets the current texture unit and the associated mapping method. Sets: SoTextureUnitElement

SEE ALSO

SoBumpMappingProperty, SoTexture2, SoTexture2Transform, SoTextureCoordinate2, SoTextureCoordinateBinding, SoTextureCoordinateFunction.

See related examples:

MultiTexture

---

Member Enumeration Documentation

enum SoTextureUnit::MappingMethod

Mapping method possible values.

Enumerator:

BUMP_MAPPING	The texture stored in SoTexture2 is used as a bump map texture.
IMAGE_MAPPING	The texture stored in SoTexture2 is used as an image map texture.

---

Constructor & Destructor Documentation

SoTextureUnit::SoTextureUnit

(

)

Constructor.

---

Member Function Documentation

static SoType SoTextureUnit::getClassTypeId

(

)

[static]

Returns the type identifier for this class.

Reimplemented from SoNode.

static unsigned int SoTextureUnit::getMaxTextureUnit

(

SoState *

state = NULL

)

[static]

Returns the maximum number of texture units.

This is the max which can be used when a shader is on state. Without shaders, only the first 4 units (0..3) can be used.

virtual SoType SoTextureUnit::getTypeId

(

)

const [virtual]

Returns the type identifier for this specific instance.

Reimplemented from SoNode.

---

Member Data Documentation

SoSFEnum SoTextureUnit::mappingMethod

Specifies the mapping method used for texture mapping.

Use enum MappingMethod. Default is IMAGE_MAPPING.

SoSFUInt32 SoTextureUnit::unit

Specifies the texture unit identifier.

Can range from 0 to the largest texture unit, which is getMaxTextureUnit()-1. Values greater than the largest texture unit are clamped at the largest texture unit.

---

The documentation for this class was generated from the following file:

• Inventor/nodes/SoTextureUnit.h