Drawing triangles from an array

Question

0.00/5 (No votes)

See more:

Hi.

Lets say i have an array of floats:

C#

float[] points = {1.0, 0.0, 0.5,
1.0, 1.0,
1.0, 1.0, 1.0};

This is one point on ex a triangle, where the first 3 floats are coordinates, the 2 next texture coordinates, and the last 3 normal coordinates.

How do i fast draw this in OpenGL using GLSL(If needed)?

Posted 18-Nov-12 21:46pm

Liam S. Crouch

Add a Solution

Comments

lukeer 19-Nov-12 4:28am

How would you do it without that array?

Liam S. Crouch 19-Nov-12 4:52am

glNormal3f()glTexCoord() glVertex3f();

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

lukeer · Answer 1 · 2012-11-18T23:41:00

I've never done anything in OpenGL. But referring to MSDN[^], I suggest

C#

float[] points = {
    1.0F, 0.0F, 0.5F,
    1.0F, 1.0F,
    1.0F, 1.0F, 1.0F
};

glNormal3f(points[0], points[1], points[2]);
glTexCoord2f(points[3], points[4]);
glVertex3f(points[5], points[6], points[7]);

points is an array. You can access its elements using the correct index in square brackets. Be careful not to use a non-existent index for it will result in an exception.

Have you considered to use a custom object with more descriptive naming for the floats? (I don't know the performance penalty, though). It could read something like that:

C#

// Definition of your custom data holder class
class TriangleCoordinages
{
    public float NormalX, NormalY, NormalZ;
    public float TextureX, TextureY;
    public float LocationX, LocationY, LocationZ;

    public TriangleCoordinates(
        float normalX, float normalY, float normalZ,
        float textureX, float textureY,
        float locationX, float locationY, float locationZ
    ){
        NormalX = normalX;
        NormalY = normalY;
        NormalZ = normalZ;
        TextureX = textureX;
        TextureY = textureY;
        LocationX = locationX;
        LocationY = locationY;
        LocationZ = locationZ;
    }
}

// Instantiation of a data holder object
TriangleCoordinates triangle = new TriangleCoordinates(
    1.0F, 0.0F, 0.5F,
    1.0F, 1.0F,
    1.0F, 1.0F, 1.0F
);

// Using data within the data holder object
glNormal3f(triangle.NormalX, triangle.NormalY, triangle.NormalZ);
glTexCoord2f(triangle.TextureX, triangle.TextureY);
glVertex3f(triangle.LocationX, triangle.LocationY, triangle.LocationZ);