SoIndexedTexture2 Class

Class for 2D indexed texture.

Inheritance Hierarchy

SystemObject
  OIV.InventorSoNetBase
    OIV.InventorSoDisposable
      OIV.Inventor.MiscSoBase
        OIV.Inventor.FieldsSoFieldContainer
          OIV.Inventor.NodesSoNode
            OIV.Inventor.NodesSoTexture
              OIV.Inventor.NodesSoIndexedTexture2

Namespace: OIV.Inventor.Nodes
Assembly: OIV.Inventor (in OIV.Inventor.dll) Version: 2024.2.2.0 (10.16.2.0)

Syntax

C++

Copy

public class SoIndexedTexture2 : SoTexture

Public Class SoIndexedTexture2
	Inherits SoTexture

public ref class SoIndexedTexture2 : public SoTexture

type SoIndexedTexture2 =  
    class
        inherit SoTexture
    end

The SoIndexedTexture2 type exposes the following members.

Constructors

	Name	Description
	SoIndexedTexture2	Constructor.

Top

Methods

	Name	Description
	AffectsState	Returns true if a node has an effect on the state during traversal. (Inherited from SoNode.)
	Callback	(Inherited from SoTexture.)
	ComputeDataRange	Compute the min and max value of the indexed image and put the result in OIV.Inventor.Nodes.SoIndexedTexture2.minValue and OIV.Inventor.Nodes.SoIndexedTexture2.maxValue.
	Copy	Calls Copy(false). (Inherited from SoNode.)
	Copy(Boolean)	Creates and returns an exact copy of the node. (Inherited from SoNode.)
	CopyFieldValues(SoFieldContainer)	Calls CopyFieldValues(fc, false). (Inherited from SoFieldContainer.)
	CopyFieldValues(SoFieldContainer, Boolean)	Copies the contents of fc's fields into this object's fields. (Inherited from SoFieldContainer.)
	Dispose	Releases all resources used by SoDisposable. (Inherited from SoDisposable.)
	Distribute	(Inherited from SoNode.)
	DoAction	(Overrides SoTextureDoAction(SoAction).)
	EnableNotify	Notification at this Field Container is enabled (if flag == true) or disabled (if flag == false). (Inherited from SoFieldContainer.)
	Equals	Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
	FieldsAreEqual	Returns true if this object's fields are exactly equal to fc's fields. (Inherited from SoFieldContainer.)
	Get	Returns the values of the fields of this object in the Open Inventor ASCII file format in the given string. (Inherited from SoFieldContainer.)
	GetAllFields	Returns a list of fields, including the eventIn's and eventOut's. (Inherited from SoFieldContainer.)
	GetAlternateRep	This method returns the alternate represention (currently only for PDF and U3D exports). (Overrides SoNodeGetAlternateRep(SoAction).)
	GetBitmapFileType	Gets the texture file format. (Inherited from SoTexture.)
	GetBoundingBox	(Inherited from SoNode.)
	GetEventIn	Returns a the eventIn with the given name. (Inherited from SoFieldContainer.)
	GetEventOut	Returns the eventOut with the given name. (Inherited from SoFieldContainer.)
	GetField	Returns a the field of this object whose name is fieldName. (Inherited from SoFieldContainer.)
	GetFieldName	Returns the name of the given field in the fieldName argument. (Inherited from SoFieldContainer.)
	GetFields	Appends references to all of this object's fields to resultList, and returns the number of fields appended. (Inherited from SoFieldContainer.)
	GetHashCode	Overrides GetHashCode(). (Inherited from SoNetBase.)
	GetMatrix	(Inherited from SoNode.)
	GetName	Returns the name of an instance. (Inherited from SoBase.)
	GetPrimitiveCount	(Inherited from SoNode.)
	GetRenderEngineMode	Returns the supported Render engine mode. (Inherited from SoNode.)
	GetRenderUnitID	(Inherited from SoNode.)
	GetStringName	(Inherited from SoBase.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	GLRender	(Overrides SoTextureGLRender(SoGLRenderAction).)
	GLRenderBelowPath	(Inherited from SoNode.)
	GLRenderInPath	(Inherited from SoNode.)
	GLRenderOffPath	(Inherited from SoNode.)
	GrabEventsCleanup	(Inherited from SoNode.)
	GrabEventsSetup	(Inherited from SoNode.)
	HandleEvent	(Inherited from SoNode.)
	HasDefaultValues	Returns true if all of the object's fields have their default values. (Inherited from SoFieldContainer.)
	IsBoundingBoxIgnoring	This method is used by getBoundingBox action traversal to know if the current node must be traversed or not, ie the bounding should be ignored. (Inherited from SoNode.)
	IsNotifyEnabled	Notification is the process of telling interested objects that this object has changed. (Inherited from SoFieldContainer.)
	IsOverride	Returns the state of the override field. (Inherited from SoTexture.)
	IsSynchronizable	Gets the ScaleViz synchronizable state of this object. (Inherited from SoBase.)
	Pick	(Inherited from SoNode.)
	RayPick	(Inherited from SoNode.)
	Search	(Inherited from SoNode.)
	Set	Sets one or more fields in this object to the values specified in the given string, which should be a string in the Open Inventor file format. (Inherited from SoFieldContainer.)
	SetBitmapFileType	Sets the texture file format. (Inherited from SoTexture.)
	SetName	(Inherited from SoBase.)
	SetOverride	Set the state of the override field. (Inherited from SoTexture.)
	SetSynchronizable	Sets this to be a ScaleViz synchronizable object. (Inherited from SoBase.)
	SetToDefaults	Sets all fields in this object to their default values. (Inherited from SoFieldContainer.)
	ToString	Converts this SoBase structure to a human readable string. (Inherited from SoBase.)
	Touch	Marks an instance as modified, simulating a change to it. (Inherited from SoNode.)
	Write	(Inherited from SoNode.)

Top

Properties

	Name	Description
	blendColor	Color used for BLEND model. (Inherited from SoTexture.)
	borderColor	Defines border color used for border texture filtering. (Inherited from SoTexture.)
	enableBorder	Enables borders for textures. (Inherited from SoTexture.)
	enableCompressedTexture	Enables storage of textures on the graphics board in compressed form. (Inherited from SoTexture.)
	imageIndex	This field contains the in-memory representation of the indexed texture image.
	internalFormat	Internal format for texture storage. (Inherited from SoTexture.)
	IsDisposable	ISafeDisposable interface implementation. (Inherited from SoDisposable.)
	magFilter	Specifies the OpenGL magFilter. (Inherited from SoTexture.)
	maxAnisotropy	Specifies on a per-texture object basis, the maximum degree of anisotropy to account for in texture filtering. (Inherited from SoTexture.)
	maxValue	See OIV.Inventor.Nodes.SoIndexedTexture2.minValue.
	minFilter	Specifies the OpenGL minFilter. (Inherited from SoTexture.)
	minValue	Specifies the range of values which is mapped onto the color map (see OIV.Inventor.Nodes.SoColorMap).
	model	Specifies how to map texture onto surface. (Inherited from SoTexture.)
	rescaleTexCoord	This field controls the way an image with non-power-of-two dimension is handled:
	UserData	Gets or sets the user data to be contained by the field container. (Inherited from SoFieldContainer.)
	wrapS	Indicates what to do when texture coordinates in the S (horizontal) direction lie outside the range 0-1. (Inherited from SoTexture.)
	wrapT	Indicates what to do when texture coordinates in the T (vertical) direction lie outside the range 0-1.

Top

Remarks

This property node defines an "indexed" texture image. In a standard texture image, e.g. OIV.Inventor.Nodes.SoTexture2, each texel contains a color value that is directly applied to the geometry. In this node each texel contains a data value that is mapped to a color value using the color map defined by the current OIV.Inventor.Nodes.SoColorMap node.

This image is stored in the current texture unit (see OIV.Inventor.Nodes.SoTextureUnit) and the texture is applied to subsequent shapes as they are rendered.

The image data is stored in an OIV.Inventor.Fields.SoSFArray2D. This array can contain different types of data (UNSIGNED_BYTE, UNSIGNED_SHORT, UNSIGNED_INT32, SIGNED_BYTE, SIGNED_SHORT, SIGNED_INT32, FLOAT).

When Open Inventor creates the OpenGL texture image from the data array, the data values must be scaled into the range of values of the texture (0-255 for an 8-bit indexed texture). The OIV.Inventor.Nodes.SoIndexedTexture2.minValue and OIV.Inventor.Nodes.SoIndexedTexture2.maxValue fields specify the range of data values that will be scaled into the range of texture values. For example, if OIV.Inventor.Nodes.SoIndexedTexture2.minValue is set to 10000 and OIV.Inventor.Nodes.SoIndexedTexture2.maxValue to 38000, all values less than or equal to 10000 will be mapped to the entry 0 of the color map and all values greater than or equal to 38000 to the last entry. The image below illustrates the process of mapping and shows how it can be used to map only the used data range to the color map:

If OIV.Inventor.Nodes.SoIndexedTexture2.minValue or OIV.Inventor.Nodes.SoIndexedTexture2.maxValue change, then the OpenGL texture must be recreated. If the texture is large, this may be time consuming. Generally it's more efficient to modify the OIV.Inventor.Nodes.SoColorMap node because the OpenGL texture corresponding to the data does not need to be recreated only the texture containing the colormap, which is normally quite small.

NOTE: Texture data values are stored with 12 bits of precision instead of the usual 8 bits, when:

ARB_fragment_program is supported by the graphics card.
The number of color map entries is greater than 256.
The texture data type has more than 8 bits of precision (i.e., not UNSIGNED_BYTE or SIGNED_BYTE).

EXAMPLE

The following example shows how to apply an indexed texture on a geometry node:

Copy

SoColorMap colorMap = new SoColorMap();
 colorMap.predefinedColorMap.SetValue( (int)SoColorMap.PredefinedColorMaps.TEMPERATURE );
 colorMap.min.Value = -1000;
 colorMap.max.Value = 20000;

SoIndexedTexture2 indexedTexture = new SoIndexedTexture2();
 indexedTexture.imageIndex.SetValue(size, (int)SoSFArray.DataTypes.SIGNED_SHORT, data);

root.AddChild( colorMap );
root.AddChild( indexedTexture );
root.AddChild( geometry );

EXAMPLE

On graphics cards supporting ARB_fragment_program , the model field will be ignored and multitexturing will not work. It is possible to circumvent this limitation by using a custom shader. The following GLSL code shows how to do multitexturing between two indexed textures sharing the same color map:

Copy

uniform sampler2D colormap;
uniform sampler2D indexedTex1; 
uniform sampler2D indexedTex2;  

void main()
{
 // Fetch first value and its assigned color
 float value1 = texture(indexedTex1, gl_TexCoord[0].xy).x;
 vec4  color1 = texture(colormap, vec2(value1, 0));

 // Fetch second and its assigned color
 float value2 = texture(indexedTex2, gl_TexCoord[0].xy).x;
 vec4  color2 = texture(colormap, vec2(value2, 0));

 // Combine the colors
 gl_FragColor = color1 * color2 * gl_Color;
}

The scene graph would be initialized like this:

Copy

SoColorMap colorMap = new SoColorMap();
. . .
SoIndexedTexture2 indexedTex1 = new SoIndexedTexture2();
. . .
SoIndexedTexture2 indexedTex2 = new SoIndexedTexture2();
. . .

SoFragmentShader fragShader = new SoFragmentShader();
 fragShader.sourceProgram.Value = "filename.glsl";

SoShaderParameter1i parameter = new SoShaderParameter1i();
 parameter.name.Value = "colorMap";
 parameter.value.Value = 0;
 fragShader.parameter[0] = parameter;

parameter = new SoShaderParameter1i();
 parameter.name.Value = "indexedTex1";
 parameter.value.Value = 1;
 fragShader.parameter[1] = parameter;

parameter = new SoShaderParameter1i();
 parameter.name.Value = "indexedTex2";
 parameter.value.Value = 2;
 fragShader.parameter[2] = parameter;

SoShaderProgram shaderProgram = new SoShaderProgram();
 shaderProgram.shaderObject.SetValue(fragShader);

SoTextureUnit textureUnit = new SoTextureUnit();
 textureUnit.unit.Value = 2;  //Texture unit for the second indexed texture

root.AddChild(colorMap);      //Color map must come first (texture unit 1)
root.AddChild(indexedTex1);   //First indexed texture (texture unit 0)
root.AddChild(textureUnit);
root.AddChild(indexedTex2);   //Second indexed texture (texture unit 2)
root.AddChild(shaderProgram);
root.AddChild(geometry);

FILE FORMAT/DEFAULT

IndexedTexture2 {
minValue 0
maxValue 0
imageIndex 0 0
rescaleTexCoord false
wrapS REPEAT
wrapT REPEAT
model MODULATE
blendColor 0 0 0
enableBorder false
borderColor 0 0 0 0
maxAnisotropy 1.0
minFilter AUTO
magFilter AUTO
useAutoMipmap false
internalFormat AUTO_INTERNAL_FORMAT
}

ACTION BEHAVIOR

OIV.Inventor.Actions.SoGLRenderAction, OIV.Inventor.Actions.SoCallbackAction Sets: OIV.Inventor.Elements.SoTextureImageElement

Reference

OIV.Inventor.Nodes Namespace

OIV.Inventor.Nodes.SoTexture2Transform

OIV.Inventor.Nodes.SoTextureCoordinate2

OIV.Inventor.Nodes.SoTextureCoordinateFunction

OIV.Inventor.Nodes.SoColorMap

OIV.Inventor.Fields.SoSFArray2D