https://gitlab.freedesktop.org/mesa/kmscube.git
and see tearing on my Pi4 at the top of the screen.
So I went back to kmscube and modified the beginning of draw_cube_smooth (in cube-smooth.c) to draw a moving vertical red line and see tearing there too.
The beginning of draw_cube_smooth now looks like:
Code: Select all
static void draw_cube_smooth(unsigned i)
{
ESMatrix modelview;
/* clear the color buffer */
glClearColor(0, 0, 0, 1.0);
glClear(GL_COLOR_BUFFER_BIT);
glEnable(GL_SCISSOR_TEST);
glClearColor(1.0, 0, 0, 1.0);
glScissor(i * 10 % (wd - 10), 0, 10, ht);
glClear(GL_COLOR_BUFFER_BIT);
glDisable(GL_SCISSOR_TEST);
PS: I see tearing on a Pi3 as well, but it disappears after a few seconds.