Seriously strange things - Printable Version

Code:

//Make space for particle limits and fill it from OGL call.

    GLfloat sizes[2];

    glGetFloatv(GL_ALIASED_POINT_SIZE_RANGE, sizes);

    

    //Enable point sprites and set params for points.

    float quadratic[] =  { 1.0f, 0.0f, 0.01f };

    glPointParameterfvARB( GL_POINT_DISTANCE_ATTENUATION_ARB, quadratic );

    glPointParameterfARB( GL_POINT_FADE_THRESHOLD_SIZE_ARB, 60.0f );

    

    //Tell it the max and min sizes we can use using our pre-filled array.

    glPointParameterfARB( GL_POINT_SIZE_MIN_ARB, sizes[0] );

    glPointParameterfARB( GL_POINT_SIZE_MAX_ARB, sizes[1] );

    

    //Tell OGL to replace the coordinates upon drawing.

    glTexEnvi(GL_POINT_SPRITE_ARB, GL_COORD_REPLACE_ARB, GL_TRUE);

    

    //Set the size of the points.

    glPointSize(16.0f);

Code:

//Create the texture we want to use.

    BBSTexture* t = textures[0];

    

    //Enable our texture type (in this case, it must be GL_TEXTURE_2D)

    glEnable([t type]);

    

    //Bind the texture data.

    glBindTexture([t type], [t data]);

    

    //Enable blending and set for particles

    glEnable(GL_BLEND);

    glBlendFunc(GL_SRC_ALPHA, GL_ONE);

    

    //Turn off depth masking so particles in front will not occlude particles behind them.

    //glDepthMask(GL_FALSE);

    

    glDisable(GL_DEPTH_TEST);

    

    //Save the current transform.

    glPushMatrix();

    

    glEnable(GL_POINT_SPRITE_ARB);

    

    //Begin drawing points.

    glBegin(GL_POINTS);

    //Iterate through our particles, setting the color and specifying their position.

    for (Particle* p in particles)

    {

        glColor4f([[p color] magnitudeX], [[p color] magnitudeY] - [p lifespan], [[p color] magnitudeZ] - ([p lifespan] * 2), [[p color] magnitudeW]);

        glVertex3f([p x], [p y], [p z]);

    }

    glEnd();    //Stop drawing points.

    

    //glDepthMask(GL_TRUE);

    

    glDisable(GL_POINT_SPRITE_ARB);

    

    glEnable(GL_DEPTH_TEST);

    

    //glDisable(GL_BLEND);

    

    //Return to the previous matrix.

    glPopMatrix();