Use a dummy transmittance lookup texture to render the lookup in Sky

Ideally the compiler should optimize the shader so the texture isn't
used, but that'll take some extra effort to implement.

diff --git a/source/effects/sky.cpp b/source/effects/sky.cpp
index eef6a58c4ccdedb622541fb828e2f925a3c17145..2732b7adb86d50834772d59f050de27b79700200 100644 (file)
--- a/source/effects/sky.cpp
+++ b/source/effects/sky.cpp
@@ -25,6 +25,7 @@ Sky::Sky(Renderable &c, DirectionalLight &s):
        backdrop_shprog(Resources::get_global().get<Program>("_sky_backdrop.glsl.shader")),
        sampler(Resources::get_global().get<Sampler>("_linear_clamp.samp")),
        wrap_sampler(Resources::get_global().get<Sampler>("_linear_clamp_v.samp")),
+       dummy_texture(Resources::get_global().get<Texture>("_placeholder.png")),
        rendered(false)
 {
        shdata.uniform("n_steps", 50);
@@ -112,6 +113,7 @@ void Sky::setup_frame(Renderer &renderer)
                        renderer.set_pipeline_key(this);
                        renderer.set_framebuffer(&transmittance_lookup.get_framebuffer());
                        renderer.set_shader_program(&transmittance_shprog);
+                       renderer.set_texture("transmittance_lookup", &dummy_texture, &sampler);
                        fullscreen_mesh.draw(renderer);
                }
 

diff --git a/source/effects/sky.h b/source/effects/sky.h
index 7d8933d4a65f4a6facbb7799fbb99f59293bc6bb..cb8403e77709ff0eb8ab81e9f306c3a4fa422e2b 100644 (file)
--- a/source/effects/sky.h
+++ b/source/effects/sky.h
@@ -74,6 +74,7 @@ private:
        const Program &backdrop_shprog;
        const Sampler &sampler;
        const Sampler &wrap_sampler;
+       const Texture &dummy_texture;
        mutable ProgramData shdata;
        float view_height;
        bool rendered;