AutoCAD DevBlog

Creating Procedural Texture in AutoCAD : Checker shade

By Madhukar Moogala

Procedural textures are algorithmic texture unlike textures based on images these textures are created using logic, we can created patterned textures using Checker shade.

Programmatically we can create Checker,Speckle, Wave and Tile type generic textures.

In this post I will discuss how we can create a Checker procedural texture.

void applyProceduralTextureToVase()
	{
	//Select Vase
	ads_point s_pt;
	ads_name s_ent;
	if (RTNORM != acedEntSel(_T("Select Vase"), s_ent, s_pt)) 
        return;
	AcDbObjectId vaseId = AcDbObjectId::kNull;
	if (!eOkVerify(acdbGetObjectId(vaseId, s_ent))) 
        return;
	AcDbObjectPointer<AcDbEntity> pVase(vaseId, AcDb::kForWrite);
	if (!eOkVerify(pVase.openStatus())) return;
	const ACHAR* materialName = _T("TestGeneric");
	//create Generic Procedural texture and apply to Material
	createGenericTexture(materialName);
	//Appy Material to Vase entity
	pVase->setMaterial(materialName);
	//Compute Mapper and apply to vase entity
	AcGiMapper mapper;
	mapper.setProjection(AcGiMapper::kSphere);
	mapper.setAutoTransform(AcGiMapper::kNone);
	mapper.setUTiling(AcGiMapper::kTile);
	mapper.setVTiling(AcGiMapper::kTile);
	double uScale = 1;
	double vScale = 1;
	double uOffset = 0;
	double vOffset = 0;
	AcGeMatrix3d mx;
	mx(0, 0) = uScale;
	mx(0, 1) = 0.000;
	mx(0, 2) = 0.000;
	mx(0, 3) = uScale*uOffset;
	mx(1, 0) = 0.000;
	mx(1, 1) = vScale;
	mx(1, 2) = 0.000;
	mx(1, 3) = vScale*vOffset;
	mx(2, 0) = 0.000;
	mx(2, 1) = 0.000;
	mx(2, 2) = 1.000;
	mx(2, 3) = 0.000;
	mx(3, 0) = 0.000;
	mx(3, 1) = 0.000;
	mx(3, 2) = 0.000;
	mx(3, 3) = 1.000;

	mapper.setTransform(mx);
	//Apply Mapper to Vase 
	pVase->setMaterialMapper(mapper);

	}

Util Methods:

AcDbObjectId createMaterial(const ACHAR*& name)
{
    // Open the material dictionary for writing
    AcDbDictionary *pMaterialDict;
    Acad::ErrorStatus dbStatus;
    AcDbObjectId mtlId;
	#define cwDB acdbHostApplicationServices()->workingDatabase()
    if (cwDB->getMaterialDictionary(pMaterialDict,
				  AcDb::kForWrite) == Acad::eOk)
    {
        // Create and initialize the material
        AcDbMaterial *pMaterialObj = new AcDbMaterial();
		// Name
        pMaterialObj->setName(name);
		 // Diffuse color
        AcCmEntityColor acClr;
		acClr.setRGB(153, 153, 153);
		AcGiMaterialColor color;
        color.setMethod(AcGiMaterialColor::kOverride);
        color.setFactor(1.0);
        color.setColor(acClr);
		// Diffuse texture
        pMaterialObj->setDiffuse(color, AcGiMaterialMap());
		  // Ambient and specular color
        AcGiMaterialColor inheritColor;
        color.setFactor(0.5);
        pMaterialObj->setAmbient(color);
        pMaterialObj->setSpecular(color, AcGiMaterialMap(), 0.5);
		 // Add material to dictionary
        dbStatus = pMaterialDict->setAt(name, pMaterialObj, mtlId);
        assert(dbStatus == Acad::eOk);
		// Close the material and dictionary
        pMaterialObj->close();
        pMaterialDict->close();
    }
    return mtlId;

	}

void createGenericTexture(const ACHAR*& materialName)
	{
	// This example is a simple procedural texture
	
	//Create a Material "Test"
	AcDbObjectId mtlId = createMaterial(materialName);
	AcDbObjectPointer<AcDbMaterial> mtl(mtlId, AcDb::kForWrite);
	if (Acad::eOk != mtl.openStatus())
		return;
	mtl->setMode(AcGiMaterialTraits::kRealistic);
	AcCmColor clr1, clr2;
	clr1.setRGB(0, 127, 255);
	clr2.setRGB(191, 255, 0);
	
	AcGiVariant varData;
	// the Shader element
	varData.setElem(_T("Shader"), AcGiVariant(_T("Checker"))); 
	//the soften element
	varData.setElem(_T("Soften"), AcGiVariant(0.0)); 
	AcGiVariant clr1Data,clr2Data;
		clr1Data.setElem(_T("Color"), AcGiVariant(clr1));
	varData.setElem(_T("Map1"), clr1Data);
		clr2Data.setElem(_T("Color"), AcGiVariant(clr2));
	varData.setElem(_T("Map2"), clr2Data);
	//Set Variant Data to Texture
	AcGiGenericTexture texture;
	texture.setDefinition(varData);
	//Set Texture to Material Map
	AcGiMaterialMap map;
	map.setTexture(&texture);
	//Apply Texture Material Map to Material
	mtl->setDiffuse(AcGiMaterialColor(), map);

	}

ScreenCast Demo

Check needed to determine if a text is present in a Linetype using .NET

By Deepak Nadig

Recently, an ADN partner requested for a method to check if a text is contained in a Linetype before extracting the text.

To extract a text, LinetypeTableRecord.TextAt is used and it returns eNotApplicable error when text is not present at index in the record. To avoid this, null id check using LinetypeTableRecord.ShapeStyleAt can be used. This method returns null, if text is not present at an index in the LinetypeTableRecord.

Here is a quick sample to check if text is present prior to extraction of the text :  

[CommandMethod("lineTypeText")]
public void lineTypeText() {
Document doc = Application.DocumentManager.MdiActiveDocument;
Database db = doc.Database;
Transaction tr = db.TransactionManager.StartTransaction();

Editor ed = doc.Editor;
using (tr) {
DBObject tmpObj = tr.GetObject(db.LinetypeTableId, OpenMode.ForRead);
LinetypeTable pLineTable = (LinetypeTable)tmpObj;
if ((pLineTable != null)) {
	foreach (ObjectId tblRecId in pLineTable) {

		LinetypeTableRecord pLineType = (LinetypeTableRecord)tr.GetObject(tblRecId, OpenMode.ForRead);
		if ((pLineType != null)) {
			for (int dash = 0; dash < pLineType.NumDashes; dash++) {
				/* LinetypeTableRecord.ShapeStyleAt returns the ObjectId of the TextStyleTableRecord of the shape 
				(or textStyle if it's a text string instead of a shape) at position index in the LinetypeTableRecord.
				If there is no shape or text at index, then Null is returned.*/
				ObjectId objIdShape = pLineType.ShapeStyleAt(dash);
				if (objIdShape != ObjectId.Null) {
					string pText = "";
					pText = pLineType.TextAt(dash);
					if (pText == "") {
						ed.WriteMessage("no dash text ");
					} else {
						ed.WriteMessage("dash :" + dash.ToString());
						ed.WriteMessage("\ndash text :" + pText);
					}

				}
			}
		}
	}
}

}
}

The output generated by this code snippet is as seen in this screenshot :

  

 

 

 

 

 

 

 

 

 

 

Update:  The above code is not equipped to handle shape\symbol in linetype. You can use the LinetypeTableRecord.ShapeNumberAt API to determine if shape exists. It returns 0 if shape does not exist. Below is the modified code that Can be used for testing : 

[CommandMethod("lineTypeText")]
public void lineTypeText()
{
    Document doc = Application.DocumentManager.MdiActiveDocument;
    Database db = doc.Database;
    Transaction tr = db.TransactionManager.StartTransaction();
 
    Editor ed = doc.Editor;
    using (tr)
    {
        DBObject tmpObj = tr.GetObject(db.LinetypeTableId, OpenMode.ForRead);
        LinetypeTable pLineTable = (LinetypeTable)tmpObj;
        if ((pLineTable != null))
        {
            foreach (ObjectId tblRecId in pLineTable)
            {
 
                LinetypeTableRecord pLineType = (LinetypeTableRecord)tr.GetObject(tblRecId, OpenMode.ForRead);
                if ((pLineType != null))
                {
                    for (int dash = 0; dash < pLineType.NumDashes; dash++)
                    {
                        ObjectId objIdShape = pLineType.ShapeStyleAt(dash); //If there is no shape or text at index, then Null is returned.
 
                        int shpNum = pLineType.ShapeNumberAt(dash);
                        if (objIdShape != ObjectId.Null)
                        {
                            ed.WriteMessage("text or shape exist;");
                            string pText = "";
                            //returns 0 if there is no shape\symbol at the index, which means text exist in this context
                            if (shpNum == 0)
                            {
                                pText = pLineType.TextAt(dash);                                       
                                ed.WriteMessage(" dash text :" + pText );
                            }
                            ed.WriteMessage("\n");
 
                        }
                    }
                }
            }
        }
 
    }
}