Scene+System: Enable model loading

.gitmodules

@@ -19,3 +19,6 @@
 [submodule "inferno/vendor/ruc"]
 	path = vendor/ruc
 	url = https://github.com/Riyyi/ruc
+[submodule "inferno/vendor/assimp"]
+	path = vendor/assimp
+	url = https://github.com/assimp/assimp

README.org

@@ -33,6 +33,7 @@ $ cmake .. && make
 
 * Libraries
 
+- [[https://github.com/assimp/assimp][assimp]]
 # - [[https://github.com/bulletphysics/bullet3][Bullet]]
 - [[https://github.com/skypjack/entt][EnTT]]
 - [[https://github.com/Dav1dde/glad][glad]]

assets/glsl/batch-3d.frag

@@ -0,0 +1,49 @@
+#version 450 core
+
+layout(location = 0) out vec4 color;
+
+in vec3 v_normal;
+in vec2 v_textureCoordinates;
+in flat float v_textureIndex;
+
+uniform sampler2D u_textures[32];
+
+void main()
+{
+	vec4 textureColor = vec4(1.0f);
+	switch(int(v_textureIndex)) {
+		case 0:  break; // Texture unit 0 is reserved for no texture
+		case 1:  textureColor *= texture(u_textures[1],  v_textureCoordinates); break;
+		case 2:  textureColor *= texture(u_textures[2],  v_textureCoordinates); break;
+		case 3:  textureColor *= texture(u_textures[3],  v_textureCoordinates); break;
+		case 4:  textureColor *= texture(u_textures[4],  v_textureCoordinates); break;
+		case 5:  textureColor *= texture(u_textures[5],  v_textureCoordinates); break;
+		case 6:  textureColor *= texture(u_textures[6],  v_textureCoordinates); break;
+		case 7:  textureColor *= texture(u_textures[7],  v_textureCoordinates); break;
+		case 8:  textureColor *= texture(u_textures[8],  v_textureCoordinates); break;
+		case 9:  textureColor *= texture(u_textures[9],  v_textureCoordinates); break;
+		case 10: textureColor *= texture(u_textures[10], v_textureCoordinates); break;
+		case 11: textureColor *= texture(u_textures[11], v_textureCoordinates); break;
+		case 12: textureColor *= texture(u_textures[12], v_textureCoordinates); break;
+		case 13: textureColor *= texture(u_textures[13], v_textureCoordinates); break;
+		case 14: textureColor *= texture(u_textures[14], v_textureCoordinates); break;
+		case 15: textureColor *= texture(u_textures[15], v_textureCoordinates); break;
+		case 16: textureColor *= texture(u_textures[16], v_textureCoordinates); break;
+		case 17: textureColor *= texture(u_textures[17], v_textureCoordinates); break;
+		case 18: textureColor *= texture(u_textures[18], v_textureCoordinates); break;
+		case 19: textureColor *= texture(u_textures[19], v_textureCoordinates); break;
+		case 20: textureColor *= texture(u_textures[20], v_textureCoordinates); break;
+		case 21: textureColor *= texture(u_textures[21], v_textureCoordinates); break;
+		case 22: textureColor *= texture(u_textures[22], v_textureCoordinates); break;
+		case 23: textureColor *= texture(u_textures[23], v_textureCoordinates); break;
+		case 24: textureColor *= texture(u_textures[24], v_textureCoordinates); break;
+		case 25: textureColor *= texture(u_textures[25], v_textureCoordinates); break;
+		case 26: textureColor *= texture(u_textures[26], v_textureCoordinates); break;
+		case 27: textureColor *= texture(u_textures[27], v_textureCoordinates); break;
+		case 28: textureColor *= texture(u_textures[28], v_textureCoordinates); break;
+		case 29: textureColor *= texture(u_textures[29], v_textureCoordinates); break;
+		case 30: textureColor *= texture(u_textures[30], v_textureCoordinates); break;
+		case 31: textureColor *= texture(u_textures[31], v_textureCoordinates); break;
+	}
+    color = textureColor;
+}

assets/glsl/batch-3d.vert

@@ -0,0 +1,21 @@
+#version 450 core
+
+layout(location = 0) in vec3 a_position;
+layout(location = 1) in vec3 a_normal;
+layout(location = 2) in vec2 a_textureCoordinates;
+layout(location = 3) in float a_textureIndex;
+
+out vec3 v_normal;
+out vec2 v_textureCoordinates;
+out flat float v_textureIndex;
+
+uniform mat4 u_projectionView;
+
+void main()
+{
+	v_normal = a_normal;
+	v_textureCoordinates = a_textureCoordinates;
+	v_textureIndex = a_textureIndex;
+	// Vclip = Camera projection * Camera view * Model transform * Vlocal
+	gl_Position = u_projectionView * vec4(a_position, 1.0f);
+}

assets/glsl/batch-font.vert

@@ -33,7 +33,4 @@ void main()
 	v_borderColor = a_borderColor;
 	v_offset = a_offset;
 	gl_Position = vec4(a_position, 1.0f);
-
-	// Vclip = Camera projection * Camera view * Model transform * Vlocal
-	// gl_Position = u_projectionView * vec4(a_position, 1.0f);
 }

src/inferno/application.cpp

@@ -80,6 +80,7 @@ Application::~Application()
 
 	RendererFont::destroy();
 	Renderer2D::destroy();
+	Renderer3D::destroy();
 	RendererCubemap::destroy();
 	RenderCommand::destroy();
 	AssetManager::destroy();
@@ -168,6 +169,7 @@ int Application::run()
 
 		std::pair<glm::mat4, glm::mat4> projectionView = m_scene->cameraProjectionView();
 		RendererCubemap::the().beginScene(projectionView.first, projectionView.second); // camera, lights, environment
+		Renderer3D::the().beginScene(projectionView.first, projectionView.second);      // camera, lights, environment
 		Renderer2D::the().beginScene(projectionView.first, projectionView.second);      // camera, lights, environment
 		RendererFont::the().beginScene(projectionView.first, projectionView.second);    // camera, lights, environment
 
@@ -175,6 +177,7 @@ int Application::run()
 		// RendererCharacter::the().drawCharacter(character, f->texture());
 
 		RendererCubemap::the().endScene();
+		Renderer3D::the().endScene();
 		Renderer2D::the().endScene();
 		RendererFont::the().endScene();
 

src/inferno/asset/asset-manager.h

@@ -31,6 +31,7 @@ public:
 	bool fastIs() const = delete;
 
 	virtual bool isFont() const { return false; }
+	virtual bool isModel() const { return false; }
 	virtual bool isShader() const { return false; }
 	virtual bool isTexture() const { return false; }
 	virtual bool isTexture2D() const { return false; }

src/inferno/asset/model.cpp

@@ -0,0 +1,110 @@
+/*
+ * Copyright (C) 2024 Riyyi
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#include <cstdint> // uint32_t
+#include <memory>  // std::shared_ptr
+
+#include "assimp/Importer.hpp"
+#include "assimp/postprocess.h"
+#include "assimp/scene.h"
+#include "assimp/texture.h"
+#include "ruc/format/log.h"
+
+#include "inferno/asset/model.h"
+#include "inferno/asset/texture.h"
+
+namespace Inferno {
+
+std::shared_ptr<Model> Model::create(std::string_view path)
+{
+	auto result = std::shared_ptr<Model>(new Model(path));
+
+	Assimp::Importer importer; // importer destructor uses RAII cleanup
+	const aiScene* scene = importer.ReadFile(
+		path.data(),
+		aiProcess_CalcTangentSpace | aiProcess_Triangulate | aiProcess_JoinIdenticalVertices | aiProcess_SortByPType);
+
+	VERIFY(scene != nullptr && (scene->mFlags & AI_SCENE_FLAGS_INCOMPLETE) == 0 && scene->mRootNode != nullptr,
+	       "assimp loading file failed: {}", importer.GetErrorString());
+
+	processScene(result, scene);
+	processNode(result, scene->mRootNode, scene);
+
+	return result;
+}
+
+void Model::processScene(std::shared_ptr<Model> model, const aiScene* scene)
+{
+	VERIFY(scene->HasMeshes(), "malformed model");
+	VERIFY(scene->mNumTextures < 2, "unsupported model type");
+
+	if (scene->mNumTextures == 1) {
+		aiTexture* texture = scene->mTextures[0];
+		model->m_texture = Texture2D::create(texture);
+	}
+}
+
+void Model::processNode(std::shared_ptr<Model> model, aiNode* node, const aiScene* scene)
+{
+	for (uint32_t i = 0; i < node->mNumMeshes; ++i) {
+		aiMesh* mesh = scene->mMeshes[node->mMeshes[i]];
+		processMesh(model, mesh, scene);
+	}
+
+	for (uint32_t i = 0; i < node->mNumChildren; ++i) {
+		processNode(model, node->mChildren[i], scene);
+	}
+}
+
+void Model::processMesh(std::shared_ptr<Model> model, aiMesh* mesh, const aiScene* scene)
+{
+	VERIFY(mesh->HasPositions(), "malformed model");
+	VERIFY(mesh->HasNormals(), "malformed model");
+
+	// Pre-allocate memory
+	model->m_vertices = std::vector<Vertex>(mesh->mNumVertices);
+
+	for (uint32_t i = 0; i < mesh->mNumVertices; ++i) {
+		aiVector3D v = mesh->mVertices[i];
+		model->m_vertices[i].position = { v.x, v.y, v.z };
+	}
+
+	// Size of vertices == size of normals
+	for (uint32_t i = 0; i < mesh->mNumVertices; ++i) {
+		aiVector3D normal = mesh->mNormals[i];
+		model->m_vertices[i].normal = { normal.x, normal.y, normal.x };
+	}
+
+	if (mesh->HasTextureCoords(0)) {
+		// Size of vertices == size of texture coordinates
+		for (uint32_t i = 0; i < mesh->mNumVertices; ++i) {
+			aiVector3D tc = mesh->mTextureCoords[0][i];
+			model->m_vertices[i].textureCoordinates = { tc.x, tc.y };
+		}
+	}
+	// TODO: position in the texture atlas
+
+	if (mesh->HasFaces()) {
+		for (uint32_t i = 0; i < mesh->mNumFaces; ++i) {
+			aiFace face = mesh->mFaces[i];
+			for (uint32_t j = 0; j < face.mNumIndices; ++j) {
+				model->m_elements.push_back(face.mIndices[j]);
+			}
+		}
+	}
+
+	ruc::debug("mesh: {:p}", mesh->mTextureCoordsNames);
+	// for (size_t i = 0; i < AI_MAX_NUMBER_OF_TEXTURECOORDS; ++i) {
+	// 	ruc::debug("mesh: {}", mesh->mTextureCoordsNames[i]);
+	// }
+
+	ruc::debug("has texture: {}", scene->HasTextures());
+
+	ruc::error("asset::model vert {}", model->m_vertices.size());
+	ruc::error("asset::model elem {}", model->m_elements.size());
+}
+
+} // namespace Inferno

src/inferno/asset/model.h

@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) 2024 Riyyi
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#pragma once
+
+#include <cstdint> // uint32_t
+#include <memory>
+#include <span>
+#include <vector>
+
+#include "assimp/scene.h"
+
+#include "inferno/asset/asset-manager.h"
+#include "inferno/render/renderer.h"
+
+namespace Inferno {
+
+class Texture2D;
+
+class Model final : public Asset {
+public:
+	virtual ~Model() {}
+
+	// Factory function
+	static std::shared_ptr<Model> create(std::string_view path);
+
+	std::span<const Vertex> vertices() const { return m_vertices; }
+	std::span<const uint32_t> elements() const { return m_elements; }
+	std::shared_ptr<Texture2D> texture() const { return m_texture; }
+
+private:
+	Model(std::string_view path)
+		: Asset(path)
+	{
+	}
+
+	static void processScene(std::shared_ptr<Model> model, const aiScene* scene);
+	static void processNode(std::shared_ptr<Model> model, aiNode* node, const aiScene* scene);
+	static void processMesh(std::shared_ptr<Model> model, aiMesh* mesh, const aiScene* scene);
+
+	virtual bool isModel() const override { return true; }
+
+private:
+	std::vector<Vertex> m_vertices;
+	std::vector<uint32_t> m_elements;
+	// Some file formats embed their texture
+	std::shared_ptr<Texture2D> m_texture;
+};
+
+} // namespace Inferno

src/inferno/asset/texture.cpp

@@ -8,6 +8,7 @@
 #include <cstdint> // uint8_t, uint32_t
 #include <memory>  // std::shared_ptr
 
+#include "assimp/texture.h"
 #include "glad/glad.h"
 #include "ruc/meta/assert.h"
 #define STB_IMAGE_IMPLEMENTATION
@@ -56,6 +57,32 @@ std::shared_ptr<Texture2D> Texture2D::create(std::string_view path)
 	return result;
 }
 
+std::shared_ptr<Texture2D> Texture2D::create(aiTexture* texture)
+{
+	auto result = std::shared_ptr<Texture2D>(new Texture2D(texture->mFilename.C_Str()));
+
+	int width = static_cast<int>(texture->mWidth);
+	int height = static_cast<int>(texture->mHeight);
+	int channels = 0;
+	unsigned char* data = reinterpret_cast<unsigned char*>(texture->pcData);
+	bool isCompressed = height == 0; // height 0 is compression, byte length stored in width variable
+
+	if (isCompressed) {
+		stbi_set_flip_vertically_on_load(0);
+		data = stbi_load_from_memory(data, width, &width, &height, &channels, STBI_default);
+	}
+	else {
+		channels = 4; // ARGB888
+		// TODO: imprement format hints? `archFormatHint'
+		VERIFY_NOT_REACHED();
+	}
+
+	result->init(width, height, channels);
+	result->create(data);
+
+	return result;
+}
+
 void Texture2D::bind(uint32_t unit) const
 {
 	// Set active unit
@@ -198,6 +225,3 @@ void TextureCubemap::create()
 }
 
 } // namespace Inferno
-
-// FIXME
-// auto texture = (type == Texture::TwoDimensional) ? Texture2D::create(path) : TextureCubemap::create(path);

src/inferno/asset/texture.h

@@ -12,6 +12,8 @@
 
 #include "inferno/asset/asset-manager.h"
 
+struct aiTexture;
+
 namespace Inferno {
 
 class Texture2D;
@@ -63,6 +65,7 @@ public:
 
 	// Factory function
 	static std::shared_ptr<Texture2D> create(std::string_view path);
+	static std::shared_ptr<Texture2D> create(aiTexture* texture);
 
 	virtual void bind(uint32_t unit = 0) const override;
 	virtual void unbind() const override;

src/inferno/component/model-component.cpp

@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2024 Riyyi
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#include "inferno/component/model-component.h"
+#include "inferno/asset/asset-manager.h"
+#include "inferno/asset/model.h"
+#include "inferno/asset/texture.h"
+
+namespace Inferno {
+
+void fromJson(const ruc::Json& json, ModelComponent& value)
+{
+	VERIFY(json.type() == ruc::Json::Type::Object);
+
+	if (json.exists("model") && json.at("model").type() == ruc::Json::Type::String) {
+		value.model = AssetManager::the().load<Model>(json.at("model").asString());
+	}
+	if (json.exists("texture") && json.at("texture").type() == ruc::Json::Type::String) {
+		value.texture = AssetManager::the().load<Texture2D>(json.at("texture").asString());
+	}
+}
+
+} // namespace Inferno

src/inferno/component/model-component.h

@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2024 Riyyi
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#pragma once
+
+#include <memory> // std::shared_ptr
+
+#include "ruc/json/json.h"
+
+#include "inferno/asset/model.h"
+#include "inferno/asset/texture.h"
+
+namespace Inferno {
+
+struct ModelComponent {
+	std::shared_ptr<Model> model;
+	std::shared_ptr<Texture2D> texture;
+};
+
+void fromJson(const ruc::Json& json, ModelComponent& value);
+
+} // namespace Inferno

src/inferno/render/buffer.cpp

@@ -321,6 +321,16 @@ void IndexBuffer::unbind() const
 	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
 }
 
+void IndexBuffer::uploadData(const void* data, uint32_t size)
+{
+	bind();
+
+	// Upload data to the GPU
+	glBufferSubData(GL_ELEMENT_ARRAY_BUFFER, 0, size, data);
+
+	unbind();
+}
+
 // -----------------------------------------
 
 VertexArray::VertexArray()

src/inferno/render/buffer.h

@@ -90,7 +90,7 @@ private:
 // -----------------------------------------
 
 // GPU memory which holds raw vertex data
-class VertexBuffer {
+class VertexBuffer { // Vertex Buffer Object, VBO
 public:
 	VertexBuffer(size_t size);
 	VertexBuffer(float* vertices, size_t size);
@@ -113,7 +113,7 @@ private:
 // -----------------------------------------
 
 // Vertices order of rendering
-class IndexBuffer {
+class IndexBuffer { // Element Buffer Object, EBO
 public:
 	IndexBuffer(uint32_t* indices, size_t size);
 	~IndexBuffer();
@@ -121,6 +121,8 @@ public:
 	void bind() const;
 	void unbind() const;
 
+	void uploadData(const void* data, uint32_t size);
+
 	uint32_t getCount() const { return m_count; }
 
 private:
@@ -131,7 +133,7 @@ private:
 // -----------------------------------------
 
 // Array that holds the vertex attributes configuration
-class VertexArray {
+class VertexArray { // Vertex Array Object, VAO
 public:
 	VertexArray();
 	~VertexArray();

src/inferno/render/render-command.cpp

@@ -4,7 +4,7 @@
  * SPDX-License-Identifier: MIT
  */
 
-#pragma once
+#include <memory> // std::shadred_ptr
 
 #include "glad/glad.h"
 #include "ruc/format/log.h"
@@ -39,9 +39,9 @@ void RenderCommand::clearColor(const glm::vec4& color)
 	glClearColor(color.r, color.g, color.b, color.a);
 }
 
-void RenderCommand::drawIndexed(const VertexArray& vertexArray, uint32_t indexCount)
+void RenderCommand::drawIndexed(std::shared_ptr<VertexArray> vertexArray, uint32_t indexCount)
 {
-	uint32_t count = indexCount ? indexCount : vertexArray.getIndexBuffer()->getCount();
+	uint32_t count = indexCount ? indexCount : vertexArray->getIndexBuffer()->getCount();
 	glDrawElements(GL_TRIANGLES, count, GL_UNSIGNED_INT, nullptr);
 }
 

src/inferno/render/render-command.h

@@ -6,7 +6,9 @@
 
 #pragma once
 
-#include "glm/ext/matrix_float4x4.hpp" // glm::mat4
+#include <memory> // std::shadred_ptr
+
+#include "glm/ext/vector_float4.hpp" // glm::vec4
 
 namespace Inferno {
 
@@ -19,7 +21,7 @@ public:
 
 	static void clear();
 	static void clearColor(const glm::vec4& color);
-	static void drawIndexed(const VertexArray& vertexArray, uint32_t indexCount = 0);
+	static void drawIndexed(std::shared_ptr<VertexArray> vertexArray, uint32_t indexCount = 0);
 
 	static void setViewport(int32_t x, int32_t y, uint32_t width, uint32_t height);
 	static void setDepthTest(bool enabled);

src/inferno/render/renderer.cpp

@@ -4,8 +4,8 @@
  * SPDX-License-Identifier: MIT
  */
 
-#include <algorithm> // std::min
-#include <utility>   // std::move
+#include <algorithm> // std::copy, std::min
+#include <span>
 
 #include "glad/glad.h"
 #include "ruc/format/log.h"
@@ -61,32 +61,7 @@ void Renderer<T>::initialize()
 	// Create vertex array
 	m_vertexArray = std::make_shared<VertexArray>();
 
-	// CPU
-	// ---------------------------------
-
-	// Generate indices
-
-	uint32_t* indices = new uint32_t[maxIndices];
-
-	uint32_t offset = 0;
-	for (uint32_t i = 0; i < maxIndices; i += indexPerQuad) {
-		indices[i + 0] = offset + 0;
-		indices[i + 1] = offset + 1;
-		indices[i + 2] = offset + 2;
-		indices[i + 3] = offset + 2;
-		indices[i + 4] = offset + 3;
-		indices[i + 5] = offset + 0;
-
-		offset += vertexPerQuad;
-	}
-
-	// GPU
-	// ---------------------------------
-
-	// Create index buffer
-	auto indexBuffer = std::make_shared<IndexBuffer>(indices, sizeof(uint32_t) * maxIndices);
-	m_vertexArray->setIndexBuffer(indexBuffer);
-	delete[] indices;
+	createElementBuffer();
 }
 
 template<typename T>
@@ -146,24 +121,56 @@ void Renderer<T>::unbind()
 	m_shader->unbind();
 }
 
+template<typename T>
+void Renderer<T>::createElementBuffer()
+{
+	// CPU
+	// ---------------------------------
+
+	// Generate indices
+
+	uint32_t* indices = new uint32_t[maxElements];
+
+	uint32_t offset = 0;
+	for (uint32_t i = 0; i < maxElements; i += elementPerQuad) {
+		indices[i + 0] = offset + 0;
+		indices[i + 1] = offset + 1;
+		indices[i + 2] = offset + 2;
+		indices[i + 3] = offset + 2;
+		indices[i + 4] = offset + 3;
+		indices[i + 5] = offset + 0;
+
+		offset += vertexPerQuad;
+	}
+
+	// GPU
+	// ---------------------------------
+
+	// Create index buffer
+	auto indexBuffer = std::make_shared<IndexBuffer>(indices, sizeof(uint32_t) * maxElements);
+	m_vertexArray->setIndexBuffer(indexBuffer);
+	delete[] indices;
+}
+
 template<typename T>
 void Renderer<T>::flush()
 {
-	if (m_quadIndex == 0) {
+	if (m_vertexIndex == 0 || m_elementIndex == 0) {
 		return;
 	}
 
+	// Upload index data to GPU
+	uploadElementBuffer();
+
 	// Upload vertex data to GPU
-	m_vertexArray->at(0)->uploadData(
-		m_vertexBufferBase,
-		m_quadIndex * vertexPerQuad * sizeof(T));
+	m_vertexArray->at(0)->uploadData(m_vertexBufferBase, m_vertexIndex * sizeof(T));
 
 	bind();
 
 	// Render
 	bool depthTest = RenderCommand::depthTest();
 	RenderCommand::setDepthTest(m_enableDepthBuffer);
-	RenderCommand::drawIndexed(*m_vertexArray, m_quadIndex * indexPerQuad);
+	RenderCommand::drawIndexed(m_vertexArray, m_elementIndex);
 	RenderCommand::setDepthTest(depthTest);
 
 	unbind();
@@ -172,7 +179,8 @@ void Renderer<T>::flush()
 template<typename T>
 void Renderer<T>::startBatch()
 {
-	m_quadIndex = 0;
+	m_vertexIndex = 0;
+	m_elementIndex = 0;
 	m_vertexBufferPtr = m_vertexBufferBase;
 
 	m_textureSlotIndex = 1;
@@ -245,7 +253,7 @@ void Renderer2D::drawQuad(const TransformComponent& transform, glm::vec4 color,
 void Renderer2D::drawQuad(const TransformComponent& transform, glm::mat4 color, std::shared_ptr<Texture> texture)
 {
 	// Create a new batch if the quad limit has been reached
-	if (m_quadIndex >= maxQuads) {
+	if (m_vertexIndex + vertexPerQuad > maxVertices || m_elementIndex + elementPerQuad > maxElements) {
 		nextBatch();
 	}
 
@@ -267,7 +275,8 @@ void Renderer2D::drawQuad(const TransformComponent& transform, glm::mat4 color,
 		m_vertexBufferPtr++;
 	}
 
-	m_quadIndex++;
+	m_vertexIndex += vertexPerQuad;
+	m_elementIndex += elementPerQuad;
 }
 
 void Renderer2D::loadShader()
@@ -366,7 +375,8 @@ void RendererCubemap::drawCubemap(const TransformComponent& transform, glm::vec4
 void RendererCubemap::drawCubemap(const TransformComponent& transform, glm::mat4 color, std::shared_ptr<Texture> texture)
 {
 	// Create a new batch if the quad limit has been reached
-	if (m_quadIndex >= maxQuads) {
+	if (m_vertexIndex + (vertexPerQuad * quadPerCube) > maxVertices
+	    || m_elementIndex + (elementPerQuad * quadPerCube) > maxElements) {
 		nextBatch();
 	}
 
@@ -380,7 +390,8 @@ void RendererCubemap::drawCubemap(const TransformComponent& transform, glm::mat4
 		m_vertexBufferPtr++;
 	}
 
-	m_quadIndex += quadPerCube;
+	m_vertexIndex += vertexPerQuad * quadPerCube;
+	m_elementIndex += elementPerQuad * quadPerCube;
 }
 
 void RendererCubemap::loadShader()
@@ -428,7 +439,7 @@ RendererFont::RendererFont(s)
 void RendererFont::drawSymbol(std::array<SymbolVertex, vertexPerQuad>& symbolQuad, std::shared_ptr<Texture> texture)
 {
 	// Create a new batch if the quad limit has been reached
-	if (m_quadIndex >= maxQuads) {
+	if (m_vertexIndex + vertexPerQuad > maxVertices || m_elementIndex + elementPerQuad > maxElements) {
 		nextBatch();
 	}
 
@@ -451,7 +462,8 @@ void RendererFont::drawSymbol(std::array<SymbolVertex, vertexPerQuad>& symbolQua
 		m_vertexBufferPtr++;
 	}
 
-	m_quadIndex++;
+	m_vertexIndex += vertexPerQuad;
+	m_elementIndex += elementPerQuad;
 }
 
 void RendererFont::loadShader()
@@ -459,4 +471,103 @@ void RendererFont::loadShader()
 	m_shader = AssetManager::the().load<Shader>("assets/glsl/batch-font");
 }
 
+// -----------------------------------------
+
+Renderer3D::Renderer3D(s)
+{
+	Renderer::initialize();
+
+	// CPU
+	// ---------------------------------
+
+	// Create array for storing quads vertices
+	m_vertexBufferBase = new Vertex[maxVertices];
+	m_vertexBufferPtr = m_vertexBufferBase;
+
+	// GPU
+	// ---------------------------------
+
+	m_enableDepthBuffer = true;
+
+	// Create vertex buffer
+	auto vertexBuffer = std::make_shared<VertexBuffer>(sizeof(Vertex) * maxVertices);
+	vertexBuffer->setLayout({
+		{ BufferElementType::Vec3, "a_position" },
+		{ BufferElementType::Vec3, "a_normal" },
+		{ BufferElementType::Vec2, "a_textureCoordinates" },
+		{ BufferElementType::Float, "a_textureIndex" },
+	});
+	m_vertexArray->addVertexBuffer(vertexBuffer);
+
+	ruc::info("Renderer3D initialized");
+}
+
+void Renderer3D::drawModel(std::span<const Vertex> vertices, std::span<const uint32_t> indices, const TransformComponent& transform, std::shared_ptr<Texture> texture)
+{
+	VERIFY(vertices.size() <= maxVertices, "model vertices too big for buffer");
+	VERIFY(indices.size() <= maxElements, "model elements too big for buffer");
+
+	// Create a new batch if the quad limit has been reached
+	if (m_vertexIndex + vertices.size() > maxVertices || m_elementIndex + indices.size() > maxElements) {
+		nextBatch();
+	}
+
+	uint32_t textureUnitIndex = addTextureUnit(texture);
+
+	// Add the vertices
+	for (auto vertex : vertices) {
+		m_vertexBufferPtr->position = transform.transform * glm::vec4(vertex.position, 1.0f);
+		m_vertexBufferPtr->normal = vertex.normal;
+		m_vertexBufferPtr->textureCoordinates = vertex.textureCoordinates;
+		m_vertexBufferPtr->textureIndex = (float)textureUnitIndex;
+		m_vertexBufferPtr++;
+	}
+
+	std::copy(indices.begin(), indices.end(), m_elementBufferPtr);
+	m_elementBufferPtr += indices.size();
+
+	m_vertexIndex += vertices.size();
+	m_elementIndex += indices.size();
+}
+
+void Renderer3D::beginScene(glm::mat4 cameraProjection, glm::mat4 cameraView)
+{
+	m_shader->bind();
+	m_shader->setFloat("u_projectionView", cameraProjection * cameraView);
+	m_shader->unbind();
+}
+
+void Renderer3D::createElementBuffer()
+{
+	// CPU
+	// ---------------------------------
+
+	// Create array for storing quads vertices
+	m_elementBufferBase = new uint32_t[maxElements];
+	m_elementBufferPtr = m_elementBufferBase;
+
+	// GPU
+	// ---------------------------------
+
+	// Create index buffer
+	auto indexBuffer = std::make_shared<IndexBuffer>(m_elementBufferBase, sizeof(uint32_t) * maxElements);
+	m_vertexArray->setIndexBuffer(indexBuffer);
+}
+
+void Renderer3D::uploadElementBuffer()
+{
+	m_vertexArray->getIndexBuffer()->uploadData(m_elementBufferBase, m_elementIndex * sizeof(uint32_t));
+}
+
+void Renderer3D::loadShader()
+{
+	m_shader = AssetManager::the().load<Shader>("assets/glsl/batch-3d");
+}
+
+void Renderer3D::startBatch()
+{
+	Renderer<Vertex>::startBatch();
+	m_elementBufferPtr = m_elementBufferBase;
+}
+
 } // namespace Inferno

src/inferno/render/renderer.h

@@ -8,6 +8,7 @@
 
 #include <cstdint> // int32_t, uint32_t
 #include <memory>  // std::shared_ptr, std::unique_ptr, std::make_shared, std::make_unique
+#include <span>
 
 #include "glm/ext/matrix_float4x4.hpp" // glm::mat4
 #include "glm/ext/vector_float2.hpp"   // glm::vec2
@@ -49,21 +50,27 @@ struct SymbolVertex {
 	float offset = 0.0f;
 };
 
+struct Vertex {
+	glm::vec3 position { 0.0f, 0.0f, 0.0f };
+	glm::vec3 normal { 1.0f, 1.0f, 1.0f };
+	glm::vec2 textureCoordinates { 0.0f, 0.0f };
+	float textureIndex = 0;
+};
+
 // -------------------------------------
 
 template<typename T>
 class Renderer {
 public:
 	static constexpr const uint32_t vertexPerQuad = 4;
-	static constexpr const uint32_t indexPerQuad = 6;
-	static constexpr const uint32_t quadPerCube = 6;
+	static constexpr const uint32_t elementPerQuad = 6;
 
 	// When to start a new batch
-	static constexpr const uint32_t maxQuads = 20000;
-	static constexpr const uint32_t maxVertices = maxQuads * vertexPerQuad;
-	static constexpr const uint32_t maxIndices = maxQuads * indexPerQuad;
+	static constexpr const uint32_t maxVertices = 60000;
+	static constexpr const uint32_t maxElements = 60000;
 	static constexpr const uint32_t maxTextureSlots = 32;
 
+public:
 	virtual void beginScene(glm::mat4 cameraProjection, glm::mat4 cameraView);
 	virtual void endScene();
 
@@ -79,6 +86,8 @@ protected:
 	void bind();
 	void unbind();
 
+	virtual void createElementBuffer();
+	virtual void uploadElementBuffer() {}
 	virtual void loadShader() = 0;
 	virtual void flush();
 	virtual void startBatch();
@@ -86,7 +95,8 @@ protected:
 
 protected:
 	// CPU quad vertices
-	uint32_t m_quadIndex { 0 };
+	uint32_t m_vertexIndex { 0 };
+	uint32_t m_elementIndex { 0 };
 	T* m_vertexBufferBase { nullptr };
 	T* m_vertexBufferPtr { nullptr };
 
@@ -102,7 +112,7 @@ protected:
 };
 
 // TOOD:
-// - Deduplicate flush()
+// v Deduplicate flush()
 //   v Add bool for disabling depth buffer
 //   - Add Size for uploadData (this is prob not needed, we got T already)
 // - Decide if its worth to remove template<T> from Renderer, just cast vertexBufferPtr before usage
@@ -114,7 +124,7 @@ class Renderer2D final
 	, public ruc::Singleton<Renderer2D> {
 public:
 	Renderer2D(s);
-	virtual ~Renderer2D() {};
+	virtual ~Renderer2D() = default;
 
 	using Singleton<Renderer2D>::destroy;
 
@@ -136,9 +146,12 @@ private:
 class RendererCubemap final
 	: public Renderer<CubemapVertex>
 	, public ruc::Singleton<RendererCubemap> {
+public:
+	static constexpr const uint32_t quadPerCube = 6;
+
 public:
 	RendererCubemap(s);
-	virtual ~RendererCubemap() {};
+	virtual ~RendererCubemap() = default;
 
 	using Singleton<RendererCubemap>::destroy;
 
@@ -161,7 +174,7 @@ class RendererFont final
 	, public ruc::Singleton<RendererFont> {
 public:
 	RendererFont(s);
-	virtual ~RendererFont() {};
+	virtual ~RendererFont() = default;
 
 	using Singleton<RendererFont>::destroy;
 
@@ -171,4 +184,31 @@ private:
 	void loadShader() override;
 };
 
+// -------------------------------------
+
+class Renderer3D final
+	: public Renderer<Vertex>
+	, public ruc::Singleton<Renderer3D> {
+public:
+	Renderer3D(s);
+	virtual ~Renderer3D() = default;
+
+	using Singleton<Renderer3D>::destroy;
+
+	virtual void beginScene(glm::mat4 cameraProjection, glm::mat4 cameraView) override;
+
+	void drawModel(std::span<const Vertex> vertices, std::span<const uint32_t> indices, const TransformComponent& transform, std::shared_ptr<Texture> texture);
+
+private:
+	void createElementBuffer() override;
+	void uploadElementBuffer() override;
+	void loadShader() override;
+	void startBatch() override;
+
+private:
+	// CPU element vertices
+	uint32_t* m_elementBufferBase { nullptr };
+	uint32_t* m_elementBufferPtr { nullptr };
+};
+
 } // namespace Inferno

src/inferno/scene/scene.cpp

@@ -19,6 +19,7 @@
 #include "inferno/component/cubemap-component.h"
 #include "inferno/component/id-component.h"
 #include "inferno/component/luascriptcomponent.h"
+#include "inferno/component/model-component.h"
 #include "inferno/component/nativescriptcomponent.h"
 #include "inferno/component/spritecomponent.h"
 #include "inferno/component/tagcomponent.h"
@@ -166,6 +167,10 @@ uint32_t Scene::loadEntity(ruc::Json components, uint32_t parentEntity)
 		auto& text = addComponent<TextAreaComponent>(entity);
 		components.at("text").getTo(text);
 	}
+	if (components.exists("model")) {
+		auto& text = addComponent<ModelComponent>(entity);
+		components.at("model").getTo(text);
+	}
 	if (components.exists("children")) {
 		VERIFY(components.at("children").type() == ruc::Json::Type::Array);
 		const auto& children = components.at("children").asArray();

src/inferno/system/rendersystem.cpp

@@ -5,9 +5,11 @@
  */
 
 #include "glm/ext/matrix_transform.hpp" // glm::translate, glm::rotate, glm::scale, glm::radians
+#include "inferno/component/model-component.h"
 #include "ruc/format/log.h"
 
 #include "inferno/component/cubemap-component.h"
+#include "inferno/component/model-component.h"
 #include "inferno/component/spritecomponent.h"
 #include "inferno/component/transformcomponent.h"
 #include "inferno/render/renderer.h"
@@ -37,6 +39,15 @@ void RenderSystem::render()
 	for (auto [entity, transform, cubemap] : cubemapView.each()) {
 		RendererCubemap::the().drawCubemap(transform, cubemap.color, cubemap.texture);
 	}
+
+	auto modelView = m_registry->view<TransformComponent, ModelComponent>();
+
+	for (auto [entity, transform, model] : modelView.each()) {
+		Renderer3D::the().drawModel(model.model->vertices(),
+		                            model.model->elements(),
+		                            transform,
+		                            model.model->texture() ? model.model->texture() : model.texture);
+	}
 }
 
 } // namespace Inferno

vendor/CMakeLists.txt

@@ -9,6 +9,16 @@ add_subdirectory(glfw)
 # Add RUC target to project
 add_subdirectory(ruc)
 
+# assimp options
+option(ASSIMP_BUILD_ASSIMP_VIEW OFF)
+option(ASSIMP_BUILD_TESTS OFF)
+option(ASSIMP_INSTALL OFF)
+option(ASSIMP_INSTALL_PDB OFF)
+option(ASSIMP_WARNINGS_AS_ERRORS OFF)
+
+# Add assimp target to project
+add_subdirectory(assimp)
+
 # Define engine source files
 file(GLOB_RECURSE GLAD "glad/*.c")
 file(GLOB LUA "lua/lua/*.c")
@@ -19,6 +29,7 @@ set(ENGINE_SOURCES ${GLAD} ${LUA})
 
 add_library(${ENGINE}-dependencies ${ENGINE_SOURCES})
 target_include_directories(${ENGINE}-dependencies PUBLIC
+	"assimp/include"
 	"glad/include"
 	"lua")
-target_link_libraries(${ENGINE}-dependencies glfw ruc ruc-test)
+target_link_libraries(${ENGINE}-dependencies glfw ruc ruc-test assimp)