the triangle you want to put on the lines, do you want it to be 3 dimensional (ie a pyramid, not a triangle?) or do you want it to just really be a triangle. also, when you say you are in 3d do you mean that your line segments all have different X,Y and Z values? or are they all on the same Z value? On 7/14/08, Edilson Vasconcelos de Melo Junior <dirso@xxxxxxxxxxxxxxxxxx> wrote: > > Hi, > > > > I'm in 3d… can you help me a little more? > > > > Thank you very much for your help, > > Dirso > > > > *De:* gameprogrammer-bounce@xxxxxxxxxxxxx [mailto: > gameprogrammer-bounce@xxxxxxxxxxxxx] *Em nome de *Alan Wolfe > *Enviada em:* segunda-feira, 14 de julho de 2008 17:38 > *Para:* gameprogrammer@xxxxxxxxxxxxx > *Assunto:* [gameprogrammer] Re: DirectX Line and Triangle > > > > Hey Dirso, > > > > Here's a plan of attack (assuming you are in 2d) > > > > Calculate the normal of the line segment to get a normalized vector > perpendicular to the line, this will be useful to figure out the vertices > for the flat back side of the triangle. Call this NX and NY. > > > > Calculate the normalized vector of the line, call this LX and LY. > > > > Find the midpoint of the line call this MX and MY. > > > > Figure out how wide and how tall you want the triangle to be, call this > TWidth and THeight. > > > > If you do the above, here's how to find each of the 3 vertices for the > triangle for each line: > > > > Vertex 1: > > *start at the midpoint > > *subtract LX,LY multiplied by TWidth/2 > > *add NX,NY * THeight/2 > > > > Vertex 2: > > *start at the midpoint > > *add LX,LY * TWidth/2 > > > > Vertex 3: > > *start at the midpoint > > *subtract LX,LY multiplied by TWidth/2 > > *subtract NX,NY * THeight/2 > > > > That will give you the vertices in a clockwise order, so watch out for back > face culling if you have clockwise culled (: > > > > > On 7/14/08, *Edilson Vasconcelos de Melo Junior* <dirso@xxxxxxxxxxxxxxxxxx> > wrote: > > Hi, > > > > I have a CustomVertex.PositionColored[] object that represents a line and > I use the DrawUserPrimitives(PrimitiveType.LineStrip, this.linePoints.Length > - 1, this.linePoints); to draw it on screen > > Now I need to draw a small triangle aligned to each line segment and one of > each vertex must "pointy" to the finish point of the segment. How can I do > that? > > Something like the attached picture, but not that ugly. > > > > Thanks, > > Dirso. > > > > > No virus found in this incoming message. > Checked by AVG - http://www.avg.com > Version: 8.0.138 / Virus Database: 270.4.10/1551 - Release Date: 14/7/2008 > 06:49 >