Make morphogenesis function give ants corect number of ommatidia according to eye phenes

src/engine/physics/ik/ik-solver.hpp

@@ -1,38 +0,0 @@
-/*
- * Copyright (C) 2023  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/>.
- */
-
-#ifndef ANTKEEPER_PHYSICS_IK_SOLVER_HPP
-#define ANTKEEPER_PHYSICS_IK_SOLVER_HPP
-
-#include <engine/math/transform.hpp>
-
-namespace physics {
-
-/**
- * 
- */
-class ik_solver
-{
-public:
-
-};
-
-} // namespace physics
-
-#endif // ANTKEEPER_PHYSICS_IK_SOLVER_HPP

src/game/ant/ant-morphogenesis.cpp

@@ -130,6 +130,43 @@ void tag_vertices
 	}
 }
 
+/**
+ * Calculates the total area of UV coordinates.
+ *
+ * @param vertex_data Vertex buffer data.
+ * @param uv_attribute Vertex UV attribute.
+ *
+ * @return Total UV area.
+ */
+float calculate_uv_area
+(
+	std::span<std::byte> vertex_data,
+	const gl::vertex_attribute& uv_attribute
+)
+{
+	std::byte* uv_data = vertex_data.data() + uv_attribute.offset;
+	
+	float sum_area = 0.0f;
+	
+	for (std::size_t i = 0; i + 2 < vertex_data.size(); i += 3)
+	{
+		const float* uv_data_a = reinterpret_cast<const float*>(uv_data + uv_attribute.stride * i);
+		const float* uv_data_b = reinterpret_cast<const float*>(uv_data + uv_attribute.stride * (i + 1));
+		const float* uv_data_c = reinterpret_cast<const float*>(uv_data + uv_attribute.stride * (i + 2));
+		
+		const float3 uva = {uv_data_a[0], uv_data_a[1], 0.0f};
+		const float3 uvb = {uv_data_b[0], uv_data_b[1], 0.0f};
+		const float3 uvc = {uv_data_c[0], uv_data_c[1], 0.0f};
+		
+		const float3 uvab = uvb - uva;
+		const float3 uvac = uvc - uva;
+		
+		sum_area += math::length(math::cross(uvab, uvac)) * 0.5f;
+	}
+	
+	return sum_area;
+}
+
 /**
  * Calculates the bounds of vertex data.
  *
@@ -166,28 +203,54 @@ void tag_vertices
 	return bounds;
 }
 
+/**
+ * Calculates a scale factor which will give ant eyes the desired number of ommatidia.
+ *
+ * @param eye_uv_area Total UV area of a single eye.
+ * @param ommatidia_count Desired number of ommatidia.
+ *
+ * @return Ommatidia scale factor.
+ */
+[[nodiscard]] float calculate_ommatidia_scale(float eye_uv_area, float ommatidia_count)
+{
+	// Side length of hexagon tiles generated by the eye shader
+	constexpr float source_side_length = 1.0f / math::sqrt_3<float>;
+	
+	// Side length of hexagon tiles that will fill UV area
+	const float target_side_length = std::sqrt((eye_uv_area * 2.0f) / (3.0f * math::sqrt_3<float> * ommatidia_count));
+	
+	return source_side_length / target_side_length;
+}
+
 /**
  * Generates an ant exoskeleton material.
  *
- * @param pigmentation Ant pigmentation phene.
- * @param sculpturing Ant sculpturing phene.
+ * @param phenome Ant phenome.
+ * @param eye_uv_area Total UV area of a single eye.
  *
  * @return Generated ant exoskeleton material.
  */
 [[nodiscard]] std::unique_ptr<render::material> generate_ant_exoskeleton_material
 (
-	const ant_pigmentation_phene& pigmentation,
-	const ant_sculpturing_phene& sculpturing
+	const ant_phenome& phenome,
+	float eye_uv_area
 )
 {
 	// Allocate copy of pigmentation material
-	std::unique_ptr<render::material> exoskeleton_material = std::make_unique<render::material>(*pigmentation.material);
+	std::unique_ptr<render::material> exoskeleton_material = std::make_unique<render::material>(*phenome.pigmentation->material);
 	
 	// Set roughness variable
-	exoskeleton_material->set_variable("roughness", std::make_shared<render::material_float>(1, sculpturing.roughness));
+	exoskeleton_material->set_variable("exoskeleton_roughness", std::make_shared<render::material_float>(1, phenome.sculpturing->roughness));
 	
 	// Set normal map variable
-	exoskeleton_material->set_variable("normal_map", std::make_shared<render::material_texture_2d>(1, sculpturing.normal_map));
+	exoskeleton_material->set_variable("exoskeleton_normal_map", std::make_shared<render::material_texture_2d>(1, phenome.sculpturing->normal_map));
+	
+	if (phenome.eyes->present)
+	{
+		// Set ommatidia scale variable
+		const float ommatidia_scale = calculate_ommatidia_scale(eye_uv_area, static_cast<float>(phenome.eyes->ommatidia_count));
+		exoskeleton_material->set_variable("ommatidia_scale", std::make_shared<render::material_float>(1, ommatidia_scale));
+	}
 	
 	return exoskeleton_material;
 }
@@ -196,9 +259,6 @@ void tag_vertices
 
 std::unique_ptr<render::model> ant_morphogenesis(const ant_phenome& phenome)
 {
-	// Generate exoskeleton material
-	std::shared_ptr<render::material> exoskeleton_material = generate_ant_exoskeleton_material(*phenome.pigmentation, *phenome.sculpturing);
-	
 	// Get body part models
 	const render::model* mesosoma_model = phenome.mesosoma->model.get();
 	const render::model* legs_model = phenome.legs->model.get();
@@ -378,6 +438,7 @@ std::unique_ptr ant_morphogenesis(const ant_phenome& phenome)
 	
 	// Get vertex attributes
 	const gl::vertex_attribute* position_attribute = nullptr;
+	const gl::vertex_attribute* uv_attribute = nullptr;
 	const gl::vertex_attribute* normal_attribute = nullptr;
 	const gl::vertex_attribute* tangent_attribute = nullptr;
 	const gl::vertex_attribute* bone_index_attribute = nullptr;
@@ -386,6 +447,10 @@ std::unique_ptr ant_morphogenesis(const ant_phenome& phenome)
 	{
 		position_attribute = &it->second;
 	}
+	if (auto it = vertex_attribute_map.find(render::vertex_attribute::uv); it != vertex_attribute_map.end())
+	{
+		uv_attribute = &it->second;
+	}
 	if (auto it = vertex_attribute_map.find(render::vertex_attribute::normal); it != vertex_attribute_map.end())
 	{
 		normal_attribute = &it->second;
@@ -715,6 +780,16 @@ std::unique_ptr ant_morphogenesis(const ant_phenome& phenome)
 	// Allocate model groups
 	model->get_groups().resize(1);
 	
+	// Calculate UV area of a single eye
+	float eye_uv_area = 0.0f;
+	if (phenome.eyes->present)
+	{
+		eye_uv_area = calculate_uv_area({vertex_buffer_data.data() + eyes_vbo_offset, vertex_buffer_data.data() + eyes_vbo_offset + eyes_vertex_count / 2}, *uv_attribute);
+	}
+	
+	// Generate exoskeleton material
+	std::shared_ptr<render::material> exoskeleton_material = generate_ant_exoskeleton_material(phenome, eye_uv_area);
+	
 	// Construct model group
 	render::model_group& model_group = model->get_groups()[0];
 	model_group.id = "exoskeleton";