1 files changed, 309 insertions, 0 deletions
diff --git a/intern/cycles/render/light.cpp b/intern/cycles/render/light.cpp
new file mode 100644
index 00000000000..74943fd0ff7
--- /dev/null
+++ b/intern/cycles/render/light.cpp
@@ -0,0 +1,309 @@
+/*
+ * Copyright 2011, Blender Foundation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "device.h"
+#include "light.h"
+#include "mesh.h"
+#include "object.h"
+#include "scene.h"
+#include "shader.h"
+
+#include "util_foreach.h"
+#include "util_progress.h"
+
+CCL_NAMESPACE_BEGIN
+
+/* Light */
+
+Light::Light()
+{
+	type = LIGHT_POINT;
+
+	co = make_float3(0.0f, 0.0f, 0.0f);
+
+	dir = make_float3(0.0f, 0.0f, 0.0f);
+	size = 0.0f;
+
+	axisu = make_float3(0.0f, 0.0f, 0.0f);
+	sizeu = 1.0f;
+	axisv = make_float3(0.0f, 0.0f, 0.0f);
+	sizev = 1.0f;
+
+	cast_shadow = true;
+	shader = 0;
+}
+
+void Light::tag_update(Scene *scene)
+{
+	scene->light_manager->need_update = true;
+}
+
+/* Light Manager */
+
+LightManager::LightManager()
+{
+	need_update = true;
+}
+
+LightManager::~LightManager()
+{
+}
+
+void LightManager::device_update_distribution(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
+{
+	/* option to always sample all point lights */
+	bool multi_light = false;
+
+	/* count */
+	size_t num_lights = scene->lights.size();
+	size_t num_triangles = 0;
+
+	foreach(Object *object, scene->objects) {
+		Mesh *mesh = object->mesh;
+		bool have_emission = false;
+
+		/* skip if we have no emission shaders */
+		foreach(uint sindex, mesh->used_shaders) {
+			Shader *shader = scene->shaders[sindex];
+
+			if(shader->sample_as_light && shader->has_surface_emission) {
+				have_emission = true;
+				break;
+			}
+		}
+
+		/* count triangles */
+		if(have_emission) {
+			for(size_t i = 0; i < mesh->triangles.size(); i++) {
+				Shader *shader = scene->shaders[mesh->shader[i]];
+
+				if(shader->sample_as_light && shader->has_surface_emission)
+					num_triangles++;
+			}
+		}
+	}
+
+	size_t num_distribution = num_triangles;
+
+	if(!multi_light)
+		num_distribution += num_lights;
+
+	/* emission area */
+	float4 *distribution = dscene->light_distribution.resize(num_distribution + 1);
+	float totarea = 0.0f;
+
+	/* triangles */
+	size_t offset = 0;
+	size_t j = 0;
+
+	foreach(Object *object, scene->objects) {
+		Mesh *mesh = object->mesh;
+		bool have_emission = false;
+
+		/* skip if we have no emission shaders */
+		foreach(uint sindex, mesh->used_shaders) {
+			Shader *shader = scene->shaders[sindex];
+
+			if(shader->sample_as_light && shader->has_surface_emission) {
+				have_emission = true;
+				break;
+			}
+		}
+
+		/* sum area */
+		if(have_emission) {
+			Transform tfm = object->tfm;
+			int object_id = (mesh->transform_applied)? -j-1: j;
+
+			for(size_t i = 0; i < mesh->triangles.size(); i++) {
+				Shader *shader = scene->shaders[mesh->shader[i]];
+
+				if(shader->sample_as_light && shader->has_surface_emission) {
+					distribution[offset].x = totarea;
+					distribution[offset].y = __int_as_float(i + mesh->tri_offset);
+					distribution[offset].z = 1.0f;
+					distribution[offset].w = __int_as_float(object_id);
+					offset++;
+
+					Mesh::Triangle t = mesh->triangles[i];
+					float3 p1 = transform(&tfm, mesh->verts[t.v[0]]);
+					float3 p2 = transform(&tfm, mesh->verts[t.v[1]]);
+					float3 p3 = transform(&tfm, mesh->verts[t.v[2]]);
+
+					totarea += triangle_area(p1, p2, p3);
+				}
+			}
+		}
+
+		if(progress.get_cancel()) return;
+
+		j++;
+	}
+
+	float trianglearea = totarea;
+
+	/* point lights */
+	if(!multi_light) {
+		float lightarea = (totarea > 0.0f)? totarea/scene->lights.size(): 1.0f;
+
+		for(size_t i = 0; i < scene->lights.size(); i++, offset++) {
+			distribution[offset].x = totarea;
+			distribution[offset].y = __int_as_float(-i-1);
+			distribution[offset].z = 1.0f;
+			distribution[offset].w = scene->lights[i]->size;
+			totarea += lightarea;
+		}
+	}
+
+	/* normalize cumulative distribution functions */
+	distribution[num_distribution].x = totarea;
+	distribution[num_distribution].y = 0.0f;
+	distribution[num_distribution].z = 0.0f;
+	distribution[num_distribution].w = 0.0f;
+
+	if(totarea > 0.0f) {
+		for(size_t i = 0; i < num_distribution; i++)
+			distribution[i].x /= totarea;
+		distribution[num_distribution].x = 1.0f;
+	}
+
+	if(progress.get_cancel()) return;
+
+	/* update device */
+	KernelIntegrator *kintegrator = &dscene->data.integrator;
+	kintegrator->use_direct_light = (totarea > 0.0f) || (multi_light && num_lights);
+
+	if(kintegrator->use_direct_light) {
+		/* number of emissives */
+		kintegrator->num_distribution = (totarea > 0.0f)? num_distribution: 0;
+
+		/* precompute pdfs */
+		kintegrator->pdf_triangles = 0.0f;
+		kintegrator->pdf_lights = 0.0f;
+
+		if(multi_light) {
+			/* sample one of all triangles and all lights */
+			kintegrator->num_all_lights = num_lights;
+
+			if(trianglearea > 0.0f)
+				kintegrator->pdf_triangles = 1.0f/trianglearea;
+			if(num_lights)
+				kintegrator->pdf_lights = 1.0f;
+		}
+		else {
+			/* sample one, with 0.5 probability of light or triangle */
+			kintegrator->num_all_lights = 0;
+
+			if(trianglearea > 0.0f) {
+				kintegrator->pdf_triangles = 1.0f/trianglearea;
+				if(num_lights)
+					kintegrator->pdf_triangles *= 0.5f;
+			}
+
+			if(num_lights) {
+				kintegrator->pdf_lights = 1.0f/num_lights;
+				if(trianglearea > 0.0f)
+					kintegrator->pdf_lights *= 0.5f;
+			}
+		}
+
+		/* CDF */
+		device->tex_alloc("__light_distribution", dscene->light_distribution);
+	}
+	else
+		dscene->light_distribution.clear();
+}
+
+void LightManager::device_update_points(Device *device, DeviceScene *dscene, Scene *scene)
+{
+	if(scene->lights.size() == 0)
+		return;
+
+	float4 *light_data = dscene->light_data.resize(scene->lights.size()*LIGHT_SIZE);
+
+	for(size_t i = 0; i < scene->lights.size(); i++) {
+		Light *light = scene->lights[i];
+		float3 co = light->co;
+		float3 dir = normalize(light->dir);
+		int shader_id = scene->shader_manager->get_shader_id(scene->lights[i]->shader);
+
+		if(!light->cast_shadow)
+			shader_id &= ~SHADER_CAST_SHADOW;
+
+		if(light->type == LIGHT_POINT) {
+			shader_id &= ~SHADER_AREA_LIGHT;
+
+			light_data[i*LIGHT_SIZE + 0] = make_float4(__int_as_float(light->type), co.x, co.y, co.z);
+			light_data[i*LIGHT_SIZE + 1] = make_float4(__int_as_float(shader_id), light->size, 0.0f, 0.0f);
+			light_data[i*LIGHT_SIZE + 2] = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
+			light_data[i*LIGHT_SIZE + 3] = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
+		}
+		else if(light->type == LIGHT_DISTANT) {
+			shader_id &= ~SHADER_AREA_LIGHT;
+
+			light_data[i*LIGHT_SIZE + 0] = make_float4(__int_as_float(light->type), dir.x, dir.y, dir.z);
+			light_data[i*LIGHT_SIZE + 1] = make_float4(__int_as_float(shader_id), light->size, 0.0f, 0.0f);
+			light_data[i*LIGHT_SIZE + 2] = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
+			light_data[i*LIGHT_SIZE + 3] = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
+		}
+		else if(light->type == LIGHT_AREA) {
+			float3 axisu = light->axisu*(light->sizeu*light->size);
+			float3 axisv = light->axisv*(light->sizev*light->size);
+
+			light_data[i*LIGHT_SIZE + 0] = make_float4(__int_as_float(light->type), co.x, co.y, co.z);
+			light_data[i*LIGHT_SIZE + 1] = make_float4(__int_as_float(shader_id), axisu.x, axisu.y, axisu.z);
+			light_data[i*LIGHT_SIZE + 2] = make_float4(0.0f, axisv.x, axisv.y, axisv.z);
+			light_data[i*LIGHT_SIZE + 3] = make_float4(0.0f, dir.x, dir.y, dir.z);
+		}
+	}
+	
+	device->tex_alloc("__light_data", dscene->light_data);
+}
+
+void LightManager::device_update(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
+{
+	if(!need_update)
+		return;
+
+	device_free(device, dscene);
+
+	device_update_points(device, dscene, scene);
+	if(progress.get_cancel()) return;
+
+	device_update_distribution(device, dscene, scene, progress);
+	if(progress.get_cancel()) return;
+
+	need_update = false;
+}
+
+void LightManager::device_free(Device *device, DeviceScene *dscene)
+{
+	device->tex_free(dscene->light_distribution);
+	device->tex_free(dscene->light_data);
+
+	dscene->light_distribution.clear();
+	dscene->light_data.clear();
+}
+
+void LightManager::tag_update(Scene *scene)
+{
+	need_update = true;
+}
+
+CCL_NAMESPACE_END
+