cvar_t r_shadow_realtime_world_shadows = {CVAR_SAVE, "r_shadow_realtime_world_shadows", "1", "enables rendering of shadows from world lights"};
cvar_t r_shadow_realtime_world_compile = {0, "r_shadow_realtime_world_compile", "1", "enables compilation of world lights for higher performance rendering"};
cvar_t r_shadow_realtime_world_compileshadow = {0, "r_shadow_realtime_world_compileshadow", "1", "enables compilation of shadows from world lights for higher performance rendering"};
-cvar_t r_shadow_realtime_world_compilesvbsp = {0, "r_shadow_realtime_world_compilesvbsp", "1", "enables svbsp optimization during compilation"};
-cvar_t r_shadow_realtime_world_compileportalculling = {0, "r_shadow_realtime_world_compileportalculling", "1", "enables portal-based culling optimization during compilation"};
+cvar_t r_shadow_realtime_world_compilesvbsp = {0, "r_shadow_realtime_world_compilesvbsp", "1", "enables svbsp optimization during compilation (slower than compileportalculling but more exact)"};
+cvar_t r_shadow_realtime_world_compileportalculling = {0, "r_shadow_realtime_world_compileportalculling", "0", "enables portal-based culling optimization during compilation (overrides compilesvbsp)"};
cvar_t r_shadow_scissor = {0, "r_shadow_scissor", "1", "use scissor optimization of light rendering (restricts rendering to the portion of the screen affected by the light)"};
cvar_t r_shadow_shadowmapping = {CVAR_SAVE, "r_shadow_shadowmapping", "0", "enables use of shadowmapping (depth texture sampling) instead of stencil shadow volumes, requires gl_fbo 1"};
cvar_t r_shadow_shadowmapping_texturetype = {CVAR_SAVE, "r_shadow_shadowmapping_texturetype", "-1", "shadowmap texture types: -1 = auto-select, 0 = 2D, 1 = rectangle, 2 = cubemap"};