On-the-fly meshes: possible at runtime with free version?

Unity Engine
1

Hi,

Apologies if this specific topic has been covered…I searched around but didn’t quite find an exact match.

I’m currently working on a genomics analysis project, where two sequences are compared using a custom algorithm. My intention was to use Unity to visualize each sequence, so: load the sequence (FASTA format in case anyone is interested) and translate each specific amino acid into a chunk of geometry, then display. I’ve worked out a basic loading mechanism, but the geometry just doesn’t want to display…I swapped in some basic code to create the verts/polys for a cube, tried opposite index ordering when it didn’t display, still nothing…hence my question (i.e. is the free version limited in this regard?).

I could create an importer for the editor and save off the ‘genomic geometry’, but I lose the main intent of the project which is to dynamically compare and pinpoint sections of similarity.

The scale of the verts I’m defining are similar to a cube already in the scene (reference object, just to confirm scene rendering is up/running). I’m assuming a default material is applied here, but maybe I shouldn’t assume this…?

Thanks in advance for any pointers. Snippet of basic code currently being used follows.

Cheers,
-Eric

public class ReadSequence : MonoBehaviour
{
string m_sequence1;
string m_sequence2;
int m_curReadIndex;
Mesh m_mesh1;
Mesh m_mesh2;
GameObject m_meshObject1;
GameObject m_meshObject2;
static UnityEngine.Object m_finalObj = null;

const float kCuboidBaseLength = 2.0f;

void Start ()
{
Logger.logMessage(“Loading sequence1”);

try
{
m_sequence1 = System.IO.File.ReadAllText(“.\sequence1.txt”);

if (m_sequence1 == “”)
return;
}

catch (Exception ex)
{
return;
}

//Skip the FASTA header and ensure only the base amino acids are present
skipFASTAHeader();

//Reading complete
Logger.logMessage(“Sequence reading #1 complete”);
//Logger.logMessage(m_sequence1);//debug/verbose purposes only

//Create the objects
Logger.logMessage(“Creating sequence objects”);
CreateObject(ref m_sequence1, ref m_mesh1, ref m_meshObject1);

Logger.logMessage(“Sequence objects constructed”);
}

[snip]

private void CreateObject (ref string inStr, ref Mesh inMesh, ref GameObject inObj)
{
Vector3 posVec = new Vector3(0.0f, 0.0f, 0.0f);
Vector3 rotVec = new Vector3(0.0f, 0.0f, 0.0f);
Vector3 objPos = new Vector3(0.0f, 0.0f, 0.0f);
Quaternion objRot = new Quaternion(0.0f, 0.0f, 0.0f, 1.0f);
int index;

//Init the mesh
inMesh = new Mesh();
Vector3[ ] vertices = new Vector3[8];
int[ ] triangles = new int[24];

Logger.logMessage(“–Allocated vector buffer”);

//Create the points
vertices[0].Set(-kCuboidBaseLength, kCuboidBaseLength, -kCuboidBaseLength);
vertices[1].Set(-kCuboidBaseLength, -kCuboidBaseLength, -kCuboidBaseLength);
vertices[2].Set(kCuboidBaseLength, -kCuboidBaseLength, -kCuboidBaseLength);
vertices[3].Set(kCuboidBaseLength, kCuboidBaseLength, -kCuboidBaseLength);

vertices[4].Set(-kCuboidBaseLength, kCuboidBaseLength, kCuboidBaseLength);
vertices[5].Set(kCuboidBaseLength, kCuboidBaseLength, kCuboidBaseLength);
vertices[6].Set(kCuboidBaseLength, -kCuboidBaseLength, kCuboidBaseLength);
vertices[7].Set(-kCuboidBaseLength, -kCuboidBaseLength, kCuboidBaseLength);

Logger.logMessage(“–Set points”);

//Create polys
index = 0;
triangles[index++] = 2;
triangles[index++] = 1;
triangles[index++] = 0;

triangles[index++] = 2;
triangles[index++] = 3;
triangles[index++] = 0;

triangles[index++] = 4;
triangles[index++] = 5;
triangles[index++] = 6;

triangles[index++] = 6;
triangles[index++] = 7;
triangles[index++] = 4;

triangles[index++] = 3;
triangles[index++] = 2;
triangles[index++] = 6;

triangles[index++] = 6;
triangles[index++] = 5;
triangles[index++] = 3;

triangles[index++] = 0;
triangles[index++] = 4;
triangles[index++] = 7;

triangles[index++] = 7;
triangles[index++] = 1;
triangles[index++] = 0;

Logger.logMessage(“–Created polys”);

//Finish the mesh
inMesh.triangles = triangles;
inMesh.vertices = vertices;
inMesh.RecalculateNormals();
inMesh.RecalculateBounds();
//inMesh.Optimize();

Logger.logMessage(“–Finalized mesh”);

//Setup the object
inObj = new GameObject(“Amino Sequence”);
inObj.AddComponent(typeof(MeshRenderer));
MeshFilter filter = inObj.GetComponent(typeof(MeshFilter)) as MeshFilter;

if (filter == null)
{
Logger.logMessage(“Adding mesh filter”);
filter = inObj.AddComponent(typeof(MeshFilter)) as MeshFilter;
}

filter.renderer.material.color = Color.white;
filter.mesh = inMesh;

Logger.logMessage(“–Added mesh and filter to object”);

//Add it to the world and make it viewable
m_finalObj = Instantiate(inObj, objPos, objRot);

if (m_finalObj == null)
Logger.logMessage(“Object instantiation failed”);

Logger.logMessage(“–Instantiated object”);
}

2

Without digging too much into your code:

It seems like you are trying to set the material color of the new mesh, yet you did not assign any material so far. So basically my guess is that the mesh generation works (once it is generated try to select it in the hierarchy and have a look at the scene view, you should see the wireframe), but as no material is applied you cannot see it directly.

So create a new material, assign that and set the color then. That should help.

Another tip for posting code on the boards: Please wrap it in [plain]your code here[/plain] tags as this will preserve your formatting.

3

http://forum.unity3d.com/threads/143875-Using-code-tags-properly

–Eric

4

another thing could be the uv’s? i wouldn’t be shure last time when i tried creating geometry at runtime experimenting my mesh didn’t showed correctly because of the normals not coming out right although i did use the funciton that says recalculate normals

5

UVs shouldn’t be the problem when assigning a solid color material.