motion blur or slow motion

[franqutrass]

how I can add "motion blur" or "slow motion" an engine of quake.

[Baker]

See Qrack's nail trails or read this for the basic idea ...

MH tutorial on simple motion blurs ...

viewtopic.php?p=16012

[r00k]

In gl_rmain.c, add this function above R_RenderView,

Code: Select all

void R_RenderSceneBlur (float alpha, GLenum format)
{
   extern int   sceneblur_texture;
   int vwidth = 2, vheight = 2;
   float vs, vt;

   if (alpha < 0.1)
      alpha = 0.1;

   while (vwidth < glwidth)
   {
      vwidth *= 2;
   }
   while (vheight < glheight)
   {
      vheight *= 2;
   }

   glViewport (glx, gly, glwidth, glheight);

   GL_Bind(sceneblur_texture);

   // go 2d
   glMatrixMode(GL_PROJECTION);
   glPushMatrix();
   glLoadIdentity ();
   glOrtho  (0, glwidth, 0, glheight, -99999, 99999);
   glMatrixMode(GL_MODELVIEW);
   glPushMatrix();
   glLoadIdentity ();

   vs = ((float)glwidth / vwidth);
   vt = ((float)glheight / vheight) ;

   glDisable (GL_DEPTH_TEST);
   glDisable (GL_CULL_FACE);
   glEnable(GL_BLEND);

   glColor4f(1, 1, 1, alpha);
   glBegin(GL_QUADS);
      glTexCoord2f(0, 0);
      glVertex2f(0, 0);
      glTexCoord2f(vs , 0);
      glVertex2f(glwidth, 0);
      glTexCoord2f(vs , vt);
      glVertex2f(glwidth, glheight);
      glTexCoord2f(0, vt);
      glVertex2f(0, glheight);
   glEnd();

   glEnable(GL_DEPTH_TEST);
   glDepthMask(1);
   glColor3f (1,1,1);   
    glDisable (GL_BLEND);   

   glMatrixMode(GL_PROJECTION);
   glPopMatrix();      
   glMatrixMode(GL_MODELVIEW);
   glPopMatrix();      

   glCopyTexImage2D(GL_TEXTURE_2D, 0, format, glx, gly, vwidth, vheight, 0);


   glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
   glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);        
}


then in R_RenderView, after R_DrawViewModel() add

Code: Select all

            if (gl_motion_blur.value)
            {
               R_RenderSceneBlur (gl_motion_blur.value, GL_RGB);
            }


u have to make your oen cvar for motion blur of course...

The blur value sets the percentage of the alpha, depends on your FPS in-game, so around 75fps, 0.2 - 0.3 seems acceptable. 0.85, and you are in a drunk haze!


EDIT: Oh just looked at MH's code, may work faster.