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- /*
- * Copyright (C) 2020 Christopher J. Howard
- *
- * This file is part of Antkeeper source code.
- *
- * Antkeeper source code 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 3 of the License, or
- * (at your option) any later version.
- *
- * Antkeeper source code 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 Antkeeper source code. If not, see <http://www.gnu.org/licenses/>.
- */
-
- #include "painting-system.hpp"
- #include "game/components/transform-component.hpp"
- #include "game/components/brush-component.hpp"
- #include "game/components/tool-component.hpp"
- #include "event/event-dispatcher.hpp"
- #include "resources/resource-manager.hpp"
- #include "scene/scene.hpp"
- #include "scene/model-instance.hpp"
- #include "math/math.hpp"
- #include "renderer/material.hpp"
- #include "renderer/model.hpp"
- #include "utility/fundamental-types.hpp"
- #include "game/entity-commands.hpp"
- #include "game/components/collision-component.hpp"
- #include "game/components/transform-component.hpp"
- #include "rasterizer/vertex-buffer.hpp"
- #include "rasterizer/vertex-attribute-type.hpp"
- #include "renderer/vertex-attributes.hpp"
- #include "geometry/mesh-functions.hpp"
- #include <limits>
-
- using namespace ecs;
-
- painting_system::painting_system(entt::registry& registry, ::event_dispatcher* event_dispatcher, ::resource_manager* resource_manager):
- entity_system(registry),
- event_dispatcher(event_dispatcher),
- resource_manager(resource_manager),
- scene(nullptr),
- painting(false)
- {
- event_dispatcher->subscribe<tool_pressed_event>(this);
- event_dispatcher->subscribe<tool_released_event>(this);
-
- max_miter_angle = math::radians(135.0f);
- decal_offset = 0.01f;
- stroke_width = 1.5f;
- min_stroke_length = 1.0f;
- min_stroke_length_squared = min_stroke_length * min_stroke_length;
- max_stroke_segments = 4096;
- current_stroke_segment = 0;
- vertex_size = 13;
- vertex_stride = sizeof(float) * vertex_size;
- vertex_count = max_stroke_segments * 6;
-
- // Create stroke model
- stroke_model = new model();
- stroke_model_group = stroke_model->add_group();
- stroke_model_group->set_material(resource_manager->load<material>("brushstroke.mtl"));
-
- // Setup stroke vbo and vao
- stroke_vbo = stroke_model->get_vertex_buffer();
- stroke_vbo->repurpose(sizeof(float) * vertex_size * vertex_count, nullptr, buffer_usage::dynamic_draw);
- stroke_model->get_vertex_array()->bind_attribute(VERTEX_POSITION_LOCATION, *stroke_vbo, 4, vertex_attribute_type::float_32, vertex_stride, 0);
- stroke_model->get_vertex_array()->bind_attribute(VERTEX_NORMAL_LOCATION, *stroke_vbo, 3, vertex_attribute_type::float_32, vertex_stride, sizeof(float) * 4);
- stroke_model->get_vertex_array()->bind_attribute(VERTEX_TEXCOORD_LOCATION, *stroke_vbo, 2, vertex_attribute_type::float_32, vertex_stride, sizeof(float) * 7);
- stroke_model->get_vertex_array()->bind_attribute(VERTEX_TANGENT_LOCATION, *stroke_vbo, 4, vertex_attribute_type::float_32, vertex_stride, sizeof(float) * 9);
-
- // Create stroke model instance
- stroke_model_instance = new model_instance();
- stroke_model_instance->set_model(stroke_model);
- stroke_model_instance->update_tweens();
-
- stroke_bounds_min.x = std::numeric_limits<float>::infinity();
- stroke_bounds_min.y = std::numeric_limits<float>::infinity();
- stroke_bounds_min.z = std::numeric_limits<float>::infinity();
- stroke_bounds_max.x = -std::numeric_limits<float>::infinity();
- stroke_bounds_max.y = -std::numeric_limits<float>::infinity();
- stroke_bounds_max.z = -std::numeric_limits<float>::infinity();
-
- midstroke = false;
- }
-
- painting_system::~painting_system()
- {
- event_dispatcher->unsubscribe<tool_pressed_event>(this);
- event_dispatcher->unsubscribe<tool_released_event>(this);
- }
-
- void painting_system::update(double t, double dt)
- {
- if (painting)
- {
- const tool_component& tool = registry.get<tool_component>(brush_entity);
-
- auto cast_result = cast_ray(tool.cursor);
- if (cast_result.has_value())
- {
- stroke_end = std::get<0>(cast_result.value());
- float3 surface_normal = std::get<1>(cast_result.value());
-
- float3 segment_difference = stroke_end - stroke_start;
- float segment_length_squared = math::dot(segment_difference, segment_difference);
- if (segment_length_squared >= min_stroke_length_squared)
- {
- float segment_length = std::sqrt(segment_length_squared);
-
- float3 segment_forward = segment_difference / segment_length;
- float3 segment_right = math::normalize(math::cross(segment_forward, surface_normal));
- float3 segment_up = math::cross(segment_right, segment_forward);
-
- float angle = std::acos(math::dot(segment_forward, float3{0, 0, -1}));
- float3 cross = math::cross(segment_forward, float3{0, 0, -1});
- if (math::dot(surface_normal, cross) < 0.0f)
- angle = -angle;
-
- math::quaternion<float> tangent_rotation = math::normalize(math::angle_axis(-angle, surface_normal));
-
- float3 p1 = stroke_start;
- float3 p2 = stroke_end;
-
- // Find miter
- float3 tangent = math::normalize(math::normalize(p2 - p1) + math::normalize(p1 - p0));
- float2 miter = float2{-tangent.z, tangent.x};
- float2 normal = float2{segment_right.x, segment_right.z};
- float miter_length = stroke_width / math::dot(miter, normal);
-
- float3 a = p0a;
- float3 b = p0b;
- float3 c = p1 - segment_right * stroke_width * 0.5f + segment_up * decal_offset;
- float3 d = p1 + segment_right * stroke_width * 0.5f + segment_up * decal_offset;
- float3 e = p2 - segment_right * stroke_width * 0.5f + segment_up * decal_offset;
- float3 f = p2 + segment_right * stroke_width * 0.5f + segment_up * decal_offset;
-
- // Adjust c and d
- bool mitered = false;
- if (midstroke)
- {
- float angle = std::acos(math::dot(math::normalize(p2 - p1), math::normalize(p1 - p0)));
- if (angle < max_miter_angle)
- {
- mitered = true;
- c = p1 - float3{miter.x, 0.0f, miter.y} * miter_length * 0.5f + segment_up * decal_offset;
- d = p1 + float3{miter.x, 0.0f, miter.y} * miter_length * 0.5f + segment_up * decal_offset;
- }
- }
-
- const float3 positions[] =
- {
- a, b, c,
- c, b, d,
- c, d, e,
- e, d, f
- };
- const float w = static_cast<float>(t);
-
- float2 texcoords[] =
- {
- {0, 0}, {1, 0}, {0, 1},
- {0, 1}, {1, 0}, {1, 1},
- {0, 0}, {1, 0}, {0, 1},
- {0, 1}, {1, 0}, {1, 1},
- };
-
- float3 tangent_positions[] =
- {
- {0, 0, 0}, {1, 0, 0}, {0, 0, 1},
- {0, 0, 1}, {1, 0, 0}, {1, 0, 1},
- {0, 0, 0}, {1, 0, 0}, {0, 0, 1},
- {0, 0, 1}, {1, 0, 0}, {1, 0, 1}
- };
-
- /// @TODO: smooth normals in middle of segment
-
- float4 tangents[12];
- for (int i = 0; i < 4; ++i)
- {
- const float3& a = tangent_positions[i * 3];
- const float3& b = tangent_positions[i * 3 + 1];
- const float3& c = tangent_positions[i * 3 + 2];
- const float2& uva = texcoords[i * 3];
- const float2& uvb = texcoords[i * 3 + 1];
- const float2& uvc = texcoords[i * 3 + 2];
-
- float3 ba = b - a;
- float3 ca = c - a;
- float2 uvba = uvb - uva;
- float2 uvca = uvc - uva;
-
- float f = 1.0f / (uvba.x * uvca.y - uvca.x * uvba.y);
- float3 tangent = math::normalize((ba * uvca.y - ca * uvba.y) * f);
- float3 bitangent = math::normalize((ba * -uvca.x + ca * uvba.x) * f);
-
- // Rotate tangent and bitangent according to segment rotation
- tangent = math::normalize(tangent_rotation * tangent);
- bitangent = math::normalize(tangent_rotation * bitangent);
-
- // Calculate sign of bitangent
- float bitangent_sign = (math::dot(math::cross(surface_normal, tangent), bitangent) < 0.0f) ? -1.0f : 1.0f;
-
- tangents[i * 3] = {tangent.x, tangent.y, tangent.z, bitangent_sign};
- tangents[i * 3 + 1] = {tangent.x, tangent.y, tangent.z, bitangent_sign};
- tangents[i * 3 + 2] = {tangent.x, tangent.y, tangent.z, bitangent_sign};
- }
-
- float vertex_data[13 * 12];
- float* v = &vertex_data[0];
- for (int i = 0; i < 12; ++i)
- {
- *(v++) = positions[i].x;
- *(v++) = positions[i].y;
- *(v++) = positions[i].z;
- *(v++) = w;
-
- *(v++) = surface_normal.x;
- *(v++) = surface_normal.y;
- *(v++) = surface_normal.z;
-
- *(v++) = texcoords[i].x;
- *(v++) = texcoords[i].y;
-
- *(v++) = tangents[i].x;
- *(v++) = tangents[i].y;
- *(v++) = tangents[i].z;
- *(v++) = tangents[i].w;
- }
-
- std::size_t segment_size = sizeof(float) * vertex_size * 6;
- if (mitered)
- {
- stroke_vbo->update((current_stroke_segment - 1) * segment_size, segment_size * 2, &vertex_data[0]);
- }
- else
- {
- stroke_vbo->update(current_stroke_segment * segment_size, segment_size, &vertex_data[vertex_size * 6]);
- }
-
- ++current_stroke_segment;
-
- stroke_model_group->set_index_count(current_stroke_segment * 6);
-
- // Update stroke bounds
- stroke_bounds_min.x = std::min<float>(stroke_bounds_min.x, std::min<float>(c.x, std::min<float>(d.x, std::min<float>(e.x, f.x))));
- stroke_bounds_min.y = std::min<float>(stroke_bounds_min.y, std::min<float>(c.y, std::min<float>(d.y, std::min<float>(e.y, f.y))));
- stroke_bounds_min.z = std::min<float>(stroke_bounds_min.z, std::min<float>(c.z, std::min<float>(d.z, std::min<float>(e.z, f.z))));
- stroke_bounds_max.x = std::max<float>(stroke_bounds_max.x, std::max<float>(c.x, std::max<float>(d.x, std::max<float>(e.x, f.x))));
- stroke_bounds_max.y = std::max<float>(stroke_bounds_max.y, std::max<float>(c.y, std::max<float>(d.y, std::max<float>(e.y, f.y))));
- stroke_bounds_max.z = std::max<float>(stroke_bounds_max.z, std::max<float>(c.z, std::max<float>(d.z, std::max<float>(e.z, f.z))));
- stroke_model->set_bounds(aabb<float>{stroke_bounds_min, stroke_bounds_max});
- stroke_model_instance->update_bounds();
-
- p0 = stroke_start;
- p0a = c;
- p0b = d;
- stroke_start = stroke_end;
- midstroke = true;
- }
- }
- }
- }
-
- void painting_system::set_scene(::scene* scene)
- {
- this->scene = scene;
- scene->add_object(stroke_model_instance);
- }
-
- void painting_system::handle_event(const tool_pressed_event& event)
- {
- if (registry.has<brush_component>(event.entity))
- {
- auto cast_result = cast_ray(event.position);
-
- if (cast_result.has_value())
- {
- brush_entity = event.entity;
- painting = true;
- stroke_start = std::get<0>(cast_result.value());
- stroke_end = stroke_start;
- p0 = stroke_start;
- p0a = p0;
- p0b = p0;
- midstroke = false;
- }
- }
- }
-
- void painting_system::handle_event(const tool_released_event& event)
- {
- if (registry.has<brush_component>(event.entity))
- {
- auto cast_result = cast_ray(ec::get_world_transform(registry, event.entity).translation);
-
- if (cast_result.has_value())
- {
- stroke_end = std::get<0>(cast_result.value());
- }
-
- brush_entity = entt::null;
- painting = false;
- }
- }
-
- std::optional<std::tuple<float3, float3>> painting_system::cast_ray(const float3& position) const
- {
- std::optional<std::tuple<float3, float3>> result;
-
- float3 intersection;
- float3 surface_normal;
- mesh::face* face = nullptr;
-
- ray<float> untransformed_ray = {position + float3{0.0f, 10000.0f, 0.0f}, {0, -1, 0}};
- float min_distance = std::numeric_limits<float>::infinity();
-
- registry.view<transform_component, collision_component>().each(
- [&](auto entity, auto& collision_transform, auto& collision)
- {
- // Transform ray into local space of collision component
- math::transform<float> inverse_transform = math::inverse(collision_transform.local);
- float3 origin = inverse_transform * untransformed_ray.origin;
- float3 direction = math::normalize(math::conjugate(collision_transform.local.rotation) * untransformed_ray.direction);
- ray<float> transformed_ray = {origin, direction};
-
- // Broad phase AABB test
- auto aabb_result = ray_aabb_intersection(transformed_ray, collision.bounds);
- if (!std::get<0>(aabb_result))
- {
- return;
- }
-
- // Narrow phase mesh test
- auto mesh_result = collision.mesh_accelerator.query_nearest(transformed_ray);
- if (mesh_result)
- {
- if (mesh_result->t < min_distance)
- {
- min_distance = mesh_result->t;
- intersection = untransformed_ray.extrapolate(min_distance);
- face = mesh_result->face;
- }
- }
- });
-
- if (face != nullptr)
- {
- surface_normal = calculate_face_normal(*face);
- result = std::make_tuple(intersection, surface_normal);
- }
-
- return result;
- }
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