1 files changed, 58 insertions, 20 deletions

diff --git a/lighting.cpp b/lighting.cpp
index 1eb4298..9f154cb 100644
--- a/lighting.cpp
+++ b/lighting.cpp
@@ -8,6 +8,8 @@ extern "C" {
 #include "plat.h"
 }
 
+#include <random>
+
 /* needs to match surface shader */
 struct GPU_Light {
 	v3f dir;
@@ -18,18 +20,19 @@ struct GPU_Light {
 
 struct GPU_Caster {
 	m4f projection;
+	m4f jittered;
 };
 
 void Lighting::init(Device* dev, int w, int h) {
 	int i;
 	Sampler_State ss{};
-	lights.init(
+	gpu_lights.init(
 		dev,
 		"Light buffer",
 		max_lights * sizeof(GPU_Light),
 		Buffer_Flags::storage_buffer
 	);
-	casters.init(
+	gpu_casters.init(
 		dev,
 		"Caster buffer",
 		max_shadows * sizeof(GPU_Caster),
@@ -43,13 +46,14 @@ void Lighting::init(Device* dev, int w, int h) {
 		shadow_res,
 		1,
 		1,
-		max_shadows,
+		shadowmap_count,
 		0
 	);
 	zero(ss_shadows, sizeof ss_shadows);
 	zero(ss_shadow_slices, sizeof ss_shadow_slices);
+	zero(occlusion, sizeof occlusion);
 	recreate(dev, w, h);
-	for (i = 0; i < max_shadows; i++) {
+	for (i = 0; i < shadowmap_count; i++) {
 		cameras[i] = 0;
 		shadow_slices[i] = dev->alias_texture(
 			shadows,
@@ -80,10 +84,10 @@ void Lighting::init(Device* dev, int w, int h) {
 
 void Lighting::destroy(Device* dev, Renderer& r) {
 	int i;
-	lights.destroy(dev);
-	casters.destroy(dev);
+	gpu_lights.destroy(dev);
+	gpu_casters.destroy(dev);
 	dev->destroy_sampler(shadow_sampler);
-	for (i = 0; i < max_shadows; i++) {
+	for (i = 0; i < shadowmap_count; i++) {
 		dev->destroy_texture(shadow_slices[i]);
 		r.destroy_camera(cameras[i]);
 	}
@@ -99,6 +103,8 @@ void Lighting::destroy_ss(Device* dev) {
 				dev->destroy_texture(ss_shadow_slices[i][j]);
 		if (ss_shadows[i])
 			dev->destroy_texture(ss_shadows[i]);
+		if (occlusion[i])
+			dev->destroy_texture(occlusion[i]);
 	}
 }
 
@@ -131,7 +137,28 @@ void Lighting::recreate(Device* dev, int w, int h) {
 				0,
 				j
 			);
+		occlusion[i] = dev->create_texture(
+			"Occlusion buffer",
+			texture_format_r32f,
+			Texture_Flags::sampleable | Texture_Flags::colour_target,
+			w,
+			h,
+			1,
+			1,
+			1,
+			0
+		);
+	}
+}
+
+Camera_Id Lighting::gm_cam(Renderer& r) {
+	int id = cam_count++;
+	Camera_Id cid = cameras[id];
+	if (!cid) {
+		cid = r.create_camera();
+		cameras[id] = cid;
 	}
+	return cid;
 }
 
 void Lighting::write_bufs(
@@ -144,6 +171,10 @@ void Lighting::write_bufs(
 	GPU_Light* ldst  = (GPU_Light*)lptr;
 	GPU_Caster* cdst = (GPU_Caster*)cptr;
 	int count = 0, ccount = 0;
+	cam_count = 0;
+	std::random_device dev;
+	std::mt19937 rng(dev());
+	std::uniform_real_distribution<float> dist6(-0.01f, 0.01f);
 	for (auto v : w.view<Sun_Light>()) {
 		GPU_Light gl;
 		Sun_Light& l = v.get<Sun_Light>();
@@ -155,15 +186,22 @@ void Lighting::write_bufs(
 		gl.colour = l.colour;
 		gl.dir = l.dir;
 		if (l.caster && ccount < max_shadows) {
+			Camera* cam[2];
 			int cid = ccount++;
-			GPU_Caster& c = cdst[cid];
-			Camera_Id camid = cameras[cid];
-			if (!camid)
-				camid = r.create_camera();
-			Camera& cam = r.get_camera(camid);
-			cam.init_shadow(l.dir, s.bound.min, s.bound.max);
-			c.projection = cam.get_proj() * cam.get_view();
-			cameras[cid] = camid;
+			Caster& caster = casters[cid];
+			GPU_Caster& gc = cdst[cid];
+			v3f jitter(
+				dist6(rng),
+				dist6(rng),
+				dist6(rng)
+			);
+			caster = Caster { gm_cam(r), gm_cam(r) };
+			cam[0] = &r.get_camera(caster.reality);
+			cam[1] = &r.get_camera(caster.jittered);
+			cam[0]->init_shadow(l.dir,          s.bound.min, s.bound.max);
+			cam[1]->init_shadow(l.dir + jitter, s.bound.min, s.bound.max);
+			gc.projection = cam[0]->get_proj() * cam[0]->get_view();
+			gc.jittered   = cam[1]->get_proj() * cam[1]->get_view();
 			gl.caster_id = cid;
 		} else
 			gl.caster_id = -1;
@@ -181,10 +219,10 @@ void Lighting::update(
 	Model_Scene& s
 ) {
 	light_count = 0;
-	write_bufs(lights.map(dev), casters.map(dev), w, r, s);
-	casters.unmap(dev);
-	lights.unmap(dev);
-	lights.update(ctx);
-	casters.update(ctx);
+	write_bufs(gpu_lights.map(dev), gpu_casters.map(dev), w, r, s);
+	gpu_casters.unmap(dev);
+	gpu_lights.unmap(dev);
+	gpu_lights.update(ctx);
+	gpu_casters.update(ctx);
 }