X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Feffects%2Fsky.cpp;h=fcb465b8bb71960fc480086ff263baeb73119fd7;hb=c8520aa336e92f2eaf9a38c3430c608520a90324;hp=8fa00cfbd4d44e884cdfadfd6268226705e039d2;hpb=06d83c11e10208478487dea864ddd7822630c391;p=libs%2Fgl.git

diff --git a/source/effects/sky.cpp b/source/effects/sky.cpp
index 8fa00cfb..fcb465b8 100644
--- a/source/effects/sky.cpp
+++ b/source/effects/sky.cpp
@@ -1,7 +1,10 @@
-#include "light.h"
+#include <msp/geometry/hypersphere.h>
+#include <msp/geometry/ray.h>
+#include "directionallight.h"
 #include "mesh.h"
 #include "renderer.h"
 #include "resources.h"
+#include "texture2d.h"
 #include "sky.h"
 
 using namespace std;
@@ -9,32 +12,29 @@ using namespace std;
 namespace Msp {
 namespace GL {
 
-Sky::Sky(Resources &resources, Renderable &r, const Light &s):
+Sky::Sky(Renderable &r, DirectionalLight &s):
 	Effect(r),
 	sun(s),
-	transmittance_shprog(resources.get<Program>("_sky_transmittance.glsl.shader")),
+	transmittance_lookup(128, 64, (COLOR_ATTACHMENT,RGB16F)),
+	transmittance_shprog(Resources::get_global().get<Program>("_sky_transmittance.glsl.shader")),
 	transmittance_lookup_dirty(true),
-	distant_shprog(resources.get<Program>("_sky_distant.glsl.shader")),
-	fullscreen_mesh(resources.get<Mesh>("_fullscreen_quad.mesh")),
-	backdrop_shprog(resources.get<Program>("_sky_backdrop.glsl.shader")),
-	sampler(resources.get<Sampler>("_linear_clamp.samp")),
-	wrap_sampler(resources.get<Sampler>("_linear_clamp_v.samp")),
+	distant(256, 128, (COLOR_ATTACHMENT,RGB16F)),
+	distant_shprog(Resources::get_global().get<Program>("_sky_distant.glsl.shader")),
+	fullscreen_mesh(Resources::get_global().get<Mesh>("_fullscreen_quad.mesh")),
+	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")),
 	rendered(false)
 {
-	transmittance_lookup.storage(RGB16F, 128, 64, 1);
-	transmittance_fbo.attach(COLOR_ATTACHMENT0, transmittance_lookup);
-
-	distant.storage(RGB16F, 256, 128, 1);
-	distant_fbo.attach(COLOR_ATTACHMENT0, distant);
-
 	shdata.uniform("n_steps", 50);
 
 	set_planet(Planet::earth());
 	set_view_height(5.0f);
 }
 
-void Sky::set_planet(const Planet &planet)
+void Sky::set_planet(const Planet &p)
 {
+	planet = p;
 	shdata.uniform("events.rayleigh_scatter", planet.rayleigh_scatter.r, planet.rayleigh_scatter.g, planet.rayleigh_scatter.b);
 	shdata.uniform("events.mie_scatter", planet.mie_scatter.r, planet.mie_scatter.g, planet.mie_scatter.b);
 	shdata.uniform("events.mie_absorb", planet.mie_absorb.r, planet.mie_absorb.g, planet.mie_absorb.b);
@@ -50,9 +50,45 @@ void Sky::set_planet(const Planet &planet)
 
 void Sky::set_view_height(float h)
 {
+	view_height = h;
 	shdata.uniform("view_height", h);
 }
 
+Color Sky::get_transmittance(const Vector3 &look_dir)
+{
+	Vector3 pos(0.0f, 0.0f, view_height);
+	Vector3 planet_center(0.0f, 0.0f, -planet.planet_radius);
+
+	Geometry::Ray<float, 3> ray(pos-planet_center, look_dir);
+	Geometry::HyperSphere<float, 3> surface(planet.planet_radius);
+	Geometry::SurfacePoint<float, 3> intersection;
+	if(surface.get_intersections(ray, &intersection, 1))
+		return Color(0.0f);
+
+	Geometry::HyperSphere<float, 3> space(planet.planet_radius+planet.atmosphere_thickness);
+	if(!space.get_intersections(ray, &intersection, 1))
+		return Color(1.0f);
+
+	float step_size = intersection.distance/50;
+
+	Color path_extinction(0.0f);
+	for(unsigned i=0; i<50; ++i)
+	{
+		Vector3 from_center = pos-planet_center;
+		float height = from_center.norm()-planet.planet_radius;
+
+		Color rayleigh_scatter = planet.rayleigh_scatter*exp(height/planet.rayleigh_density_decay);
+		Color mie_scatter = planet.mie_scatter*exp(height/planet.mie_density_decay);
+		Color mie_absorb = planet.mie_absorb*exp(height/planet.mie_density_decay);
+		Color ozone_absorb = planet.ozone_absorb*max(1.0f-abs(height-planet.ozone_band_center)/planet.ozone_band_extent, 0.0f);
+
+		path_extinction = path_extinction+(rayleigh_scatter+mie_scatter+mie_absorb+ozone_absorb)*step_size;
+		pos += look_dir*step_size;
+	}
+
+	return Color(exp(-path_extinction.r), exp(-path_extinction.g), exp(-path_extinction.b));
+}
+
 void Sky::setup_frame(Renderer &renderer)
 {
 	if(rendered)
@@ -61,21 +97,22 @@ void Sky::setup_frame(Renderer &renderer)
 	rendered = true;
 
 	shdata.uniform("light_color", sun.get_color());
-	shdata.uniform("light_dir", sun.get_position().slice<3>(0));
+	shdata.uniform("light_dir", -sun.get_direction());
+	sun.set_transmittance(get_transmittance(-sun.get_direction()));
 
 	Renderer::Push push(renderer);
 
 	if(transmittance_lookup_dirty)
 	{
 		transmittance_lookup_dirty = false;
-		Bind bind_fbo(transmittance_fbo);
+		renderer.set_framebuffer(&transmittance_lookup.get_framebuffer());
 		renderer.set_shader_program(&transmittance_shprog, &shdata);
 		fullscreen_mesh.draw(renderer);
 	}
 
-	Bind bind_fbo(distant_fbo);
+	renderer.set_framebuffer(&distant.get_framebuffer());
 	renderer.set_shader_program(&distant_shprog, &shdata);
-	renderer.set_texture("transmittance_lookup", &transmittance_lookup, &sampler);
+	renderer.set_texture("transmittance_lookup", &transmittance_lookup.get_target_texture(0), &sampler);
 	fullscreen_mesh.draw(renderer);
 
 	renderable.setup_frame(renderer);
@@ -97,10 +134,21 @@ void Sky::render(Renderer &renderer, Tag tag) const
 	Renderer::Push push(renderer);
 
 	renderer.set_shader_program(&backdrop_shprog, &shdata);
-	renderer.set_texture("distant", &distant, &wrap_sampler);
+	renderer.set_texture("distant", &distant.get_target_texture(0), &wrap_sampler);
 	fullscreen_mesh.draw(renderer);
 }
 
+void Sky::set_debug_name(const string &name)
+{
+#ifdef DEBUG
+	transmittance_lookup.set_debug_name(name+" [RT:transmittance]");
+	distant.set_debug_name(name+" [RT:distant]");
+	shdata.set_debug_name(name+" [UBO]");
+#else
+	(void)name;
+#endif
+}
+
 
 Sky::Planet::Planet():
 	rayleigh_scatter(0.0f),