But when I try with cl-opengl not: (unless (gl::features-present-p (>= :glsl-version 1. I can draw the triangle with my code in C. The primitive assembly stage takes as input all the vertices (or vertex if GLPOINTS is chosen) from the vertex (or geometry) shader that form one or more primitives and assembles all the point (s) in the primitive shape given in this case a triangle. I try today again, and I follow the tutorial below: In this example case, it generates a second triangle out of the given shape. SDFs are great for little tricks like that.I'm want write one code that works in android and linux, so I think that I should start with cl-opengl, but the android uses opengl ES, so I think that I should use opengl ES 2.0 or 3.0, but I'm confusing with all this, I'm using sdl2 for create window and cl-opengl, but how to use opengl ES in common lisp? I must write two code one in opengl ES for Android and other code in opengl for Linux? Or I can write one code in opengl ES that work in both platforms? How to write opengl ES with cl-opengl? I'm almost lost. This works for any shape, as long as the distance estimation is correct. it will connect the first and last, so if you have more than one triangle, it wont work.
if you are only rendering a single triangle at a time you can use GLLINELOOP. If you want to make the border bigger, simply subtract another term to increase its size, just like you did to make a rounded box. Use GLLINES, GLLINESTRIP, or GLLINELOOP (difference see here) with the same vertices that you use for GLTRIANGLES. This make an object with an "empty" border. Abs(de) will basically remove the inside of the object (negative distance) by making it positive. You can get a border by using the absolute value of the distance. You can get a rounded box by subtracting a term to the distance, but you already figured it out (r in your exemple). Use the box signed exact function here If you want to write it yourself, try to figure out a way of getting the closest point on the box, then return the distance to this point. You can add an infinite number of object for (almost) no added cost. SDFs performance are usually bound by the number of objects you add in your distance function this is the reason why mod/floor functions are so useful when making SDFs. Instead of computing a single object, you compute two objects.
Using a secondary box to extrude the first one is a bad idea, as it will lead to worse performance.
0 kommentar(er)
