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How can I speed up this OpenGL routine?

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Heya....I was wondering if anyone could offer me some advice on speeding up some code which appears to be the major bottleneck in my program. Its the graphics drawing part, which I appreciate is going to be a bottleneck anyway, but if I''m doing something that might be a bit slow, I want to know.... Anyway - this function is called every frame:
int DrawGLScene(GLvoid)	// Here''s Where We Do All The Drawing

        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);	// Clear The Screen And The Depth Buffer

	glBindTexture(GL_TEXTURE_2D, texture[0]);		// Select Our Texture

	glLoadIdentity();				// Reset The View Before We Draw the particles

	glTranslatef(0.0f,0.0f,zoom);			// Zoom Into The Screen (Using The Value In ''zoom'')

	glRotatef(rotate,0.0f,1.0f,0.0f);   //rotate view	

	for (int i=0; i<pList.size(); i++)				// Loop Through All The particles

		glRotatef(-rotate,0.0f,1.0f,0.0f);   //rotate view back to facing screen - draw particles face on

	return TRUE;								// Everything Went OK

OK - some explanation might be called for. Its a particle engine. pList is a vector of pointers to each particle object. Each frame, I reset the view matrix, zoom into the screen & rotate according to user set variables, then enter a loop that goes through each particle, translating to the particles location:
void particle::translate()
then rotating backwards to billboard the particle, & drawing the particle:
void particle::drawParticle(GLuint& displayList)
	if(lifespan > 5)
		glColor4ub(r,g,b,255);			//Draw at full color

		glColor4ub(r,g,b,255*lifespan/5);  //Fade out while dying

The top part sets the color, including a fade out as the particle nears the end of its life. Then I use a display list to draw the particle. The display list was defined in startup as
GLvoid BuildLists()					// Build Box Display List

	particleDisplay=glGenLists(1);				// Building One List

	glNewList(particleDisplay,GL_COMPILE);			// New Compiled box Display List

	glBegin(GL_TRIANGLE_STRIP);			// Begin Drawing The Textured Quad

		glTexCoord2f(1.0f, 1.0f); glVertex3f( 0.25f, 0.25f, 0.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f(-0.25f, 0.25f, 0.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f( 0.25f,-0.25f, 0.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f(-0.25f,-0.25f, 0.0f);
	glEnd();				// Done Drawing The Textured Quad	

Hmmm - that was a lot of code. So, assuming you''ve read this far - any hints? I was wondering if I could group those matrix translations & rotations into one operation, but can''t quite figure it out... Cheers Catfish

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Well....not a major optimisation i nthe short run,you should try to minimise the number of times you divide.Division costs more than multiplication.So in your code:


you could write this:
glColor4ub(r,g,b,255*lifespan * 0.2);

Just a little thought

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