Added comment for pixel-perfect line workaround.
authorSam Lantinga <slouken@libsdl.org>
Sat, 21 Nov 2009 07:26:52 +0000
changeset 3475 3bd01435287f
parent 3474 1edb86163d62
child 3476 ab99313951cd
Added comment for pixel-perfect line workaround.
src/video/SDL_renderer_gl.c
--- a/src/video/SDL_renderer_gl.c	Sat Nov 21 07:22:59 2009 +0000
+++ b/src/video/SDL_renderer_gl.c	Sat Nov 21 07:26:52 2009 +0000
@@ -1157,13 +1157,17 @@
 
     /* The line is half open, so we need one more point to complete the line.
      * http://www.opengl.org/documentation/specs/version1.1/glspec1.1/node47.html
+     * If we have to, we can use vertical line and horizontal line textures
+     * for vertical and horizontal lines, and then create custom textures
+     * for diagonal lines and software render those.  It's terrible, but at
+     * least it would be pixel perfect.
      */
     data->glBegin(GL_POINTS);
 #ifdef __APPLE__
     /* Mac OS X seems to always leave the second point open */
     data->glVertex2f(0.5f + x2, 0.5f + y2);
 #else
-    /* Linux seems to use the right-most or bottom-most point open */
+    /* Linux seems to leave the right-most or bottom-most point open */
     if (x1 > x2) {
         data->glVertex2f(0.5f + x1, 0.5f + y1);
     } else if (x2 > x1) {