hello,
i used code from this topic to make a sphere with points: http://www.gamedev.net/community/forums/topic.asp?topic_id=420409
for(int i = 0; i < MAX_POINTS; i++)
{
//The angle around the equator:
float xAngle = i/MAX_POINTS * PI;//Note: No longer multiply by 2
//Now create a circle that intersects
for(int j = 0; j < MAX_POINTS; j++)
{
float zAngle = j/MAX_POINTS * 2 * PI;
//Calculates the point's position
float x = cos(xAngle)*RADIUS*cos(yAngle);
float y = sin(xAngle)*RADIUS*cos(yAngle);
float z = cos(xAngle)*RADIUS*sin(yAngle);
AddPoint(x,y,z);
}
}
i took that code and made a similar piece in my app:
private ArrayList PrepareASphereOfDotsRepresentedAsVectors ( int numberOfDots )
{
ArrayList listOfDots = new ArrayList ( );
for(float i = 0; i < numberOfDots; i++)
{
double xAngle = i/numberOfDots * Math.PI;
for(float j = 0; j < numberOfDots; j++)
{
double yAngle = j/numberOfDots * 2 * Math.PI;
float x = (float)(Math.Cos(xAngle)*defaultSeparationLengthBetweenNelements*Math.Cos(yAngle));
float y = (float)(Math.Sin(xAngle)*defaultSeparationLengthBetweenNelements*Math.Cos(yAngle));
float z = (float)(Math.Cos(xAngle)*defaultSeparationLengthBetweenNelements*Math.Sin(yAngle));
listOfDots.Add ( new Vector3 (x,y,z));
}
}
return listOfDots;
}
but this generates a circle and not a sphere...what modifications should i do to make it generate a sphere?
thanks 4 ur time,
Zahid
Allahumma Salli Ala Muhammad----------------------------------------------------------By Time! Verily mankind is in loss! Except the ones who have Iman, and do righteous deeds, and advise one another towards truth, and advise one another towards patience. Quran 103:1-3. ----------------------------------------------------------Muhammed Zahid AyarSoftware Engineerzahid@ayar.org1-518-466-5631www.ayar.org----------------------------------------------------------Organize your information and knowledge with nelements.net !
hi, maybe you can use this code. note:This algorithm is not done yet, top cap and bottom cap need extra code, but this code is working
procedure MakeASphere; var pVertices: PCustomVertexArray; theta:single; sRow,sColumn:integer; sinus,cosinus,y,yOld,x,xOld:single;
procedure Vert(vIndex:integer; x,y,z:single); begin pvertices[vIndex].position:=D3DXVector3(x,y,z); D3DXVec3Normalize(pvertices[vIndex].normal,pvertices[vIndex].position); pvertices[vIndex].normal.x:=pvertices[vIndex].normal.x*3; pvertices[vIndex].normal.y:=pvertices[vIndex].normal.y*3; pvertices[vIndex].normal.z:=pvertices[vIndex].normal.z*3; end;
begin Row:=16; Column:=32;
FD3DDevice.SetFVF(D3DFVF_CUSTOMVERTEX);
pVertices:=GetMemory(sizeof(TCustomVertex)*(Column*2+2)); yOld:=0.5; xOld:=0; for sRow := 1 to Row do begin y:=cos(((D3DX_PI*sRow)/Row))/2; x:=sin((D3DX_PI*sRow)/Row); for sColumn := 1 to Column do begin theta:=(2*D3DX_PI*sColumn)/Column; sinus:=sin(theta)/2; cosinus:=cos(theta)/2; Vert((sColumn-1)*2,sinus*xOld,yOld,cosinus*xOld); Vert((sColumn-1)*2+1,sinus*x,y,cosinus*x); end; pVertices[Column*2]:=pVertices[0]; pVertices[Column*2+1]:=pVertices[1]; FD3DDevice.DrawPrimitiveUP(D3DPT_TRIANGLESTRIP, Column*2,pVertices^,sizeof(TCustomVertex)); yOld:=y; xOld:=x; end; FreeMemory(pVertices); end;
Whilst you might be trying to use Direct3D to render your results I don't see anything specific to the API/technology here. I think Maths & Physics will be a better place to get an explanation/answer [smile]
float z = (float)(defaultSeparationLengthBetweenNelements*Math.Sin(yAngle));
in your final code. What your code should be producing now is more akin to a pinched torus though, not a circle; a picture could be worth taking if the problem is not eliminated by the above change.
edit: dammit, didn't change the very last expression.
[Edited by - Darkstrike on November 15, 2006 11:34:07 AM]
yeah i tried that and it still looks like a circle...i had tried that b4 as well..
in the original code that was posted, it defined zAngle but it didnt define yAngle to i changed zAngle to yAngle..
do u think it is anything to do with that?
or is it something else?
Allahumma Salli Ala Muhammad----------------------------------------------------------By Time! Verily mankind is in loss! Except the ones who have Iman, and do righteous deeds, and advise one another towards truth, and advise one another towards patience. Quran 103:1-3. ----------------------------------------------------------Muhammed Zahid AyarSoftware Engineerzahid@ayar.org1-518-466-5631www.ayar.org----------------------------------------------------------Organize your information and knowledge with nelements.net !
Also, it's angleX that ranges from 0 to 2*Pi, and angleY ranges from -Pi/2 to Pi/2, though those things can only clip the sphere somewhat. Can you tell what's your circle's plane?
(and of course, I forgot to change the expression in my previous post; it's fixed now)
yeah the circle's plane is horizontal...here's link to a snapshot:
http://nelements.net/images/spherical.png
i have many points, how can i make them in a sphere rather than a circle?
Allahumma Salli Ala Muhammad----------------------------------------------------------By Time! Verily mankind is in loss! Except the ones who have Iman, and do righteous deeds, and advise one another towards truth, and advise one another towards patience. Quran 103:1-3. ----------------------------------------------------------Muhammed Zahid AyarSoftware Engineerzahid@ayar.org1-518-466-5631www.ayar.org----------------------------------------------------------Organize your information and knowledge with nelements.net !
ArrayList listOfDots = new ArrayList ( ); for(float i = 0; i < numberOfDots; i++) { float phi = (float)(Math.PI * i * 2) / numberOfDots; for(float j = 0; j < numberOfDots; j++) { float theta = (float)(Math.PI * j) / numberOfDots; float x = (float)(Math.Cos(phi) * Math.Sin(theta)*defaultSeparationLengthBetweenNelements); float y = (float)(Math.Sin(phi) * Math.Sin(theta)*defaultSeparationLengthBetweenNelements); float z = (float)(Math.Cos(theta)*defaultSeparationLengthBetweenNelements); listOfDots.Add ( new Vector3 (x,y,z)); } }
what it produced was a half-circle...u can check out the screenshot...any simple modification to make it a sphere? can u test a code piece and make sure it produces a sphere and then post it plz...thanks 4 ur time..
http://nelements.net/images/halfsphere.png
Allahumma Salli Ala Muhammad----------------------------------------------------------By Time! Verily mankind is in loss! Except the ones who have Iman, and do righteous deeds, and advise one another towards truth, and advise one another towards patience. Quran 103:1-3. ----------------------------------------------------------Muhammed Zahid AyarSoftware Engineerzahid@ayar.org1-518-466-5631www.ayar.org----------------------------------------------------------Organize your information and knowledge with nelements.net !
Wtf? I'm 99% sure that is a sphere, and it's definitely something in three dimensions. Can you check your Vector3 constructor isn't doing something stupid, and that your projection matrix is set up right?
