Starting to feel the love!
As explained yesterday by @xuv, #ogre3d learning curve is stiff. This morning, i started to customise the compositor. The idea is to be able to change the background color of only one part of the screen.

To do so, i just added one node in the compsitor workspace, before the “3d render” node, that do the cleaning and draw a simple quad. This simple quad uses a shader (via a material, ok it seems to be long) that uses 3 colors variables and 2 multipliers variables.

The shader itself is simplistic:

vec4 col = texture2D( tex, uv0 );

if ( uv0.y <= 0.5 ) { col = mix( bg_color, top_color, top_mult ); } else { col = mix( bg_color, bottom_color, bottom_mult ); } fragColour = col;