feat: model loader (#28)

* feat: add assimp library to vendor

* feat: add model class with loading and drawing

* feat: add ModelRendererComponent with deserialization

* feat: add model deserialization to AssetLoader

* feat: add bone weight and id to vertex

* feat: add model rendering support to ForwardRenderer

* refactor: precompute if material have textures or not and add metallicRoughness texture

* feat(litShader): add textureMetalRoughness handling

* fix(cmake): add model-renderer component to the project executable

* feat: drone model to test

* fix: remove old debug prints

* feat(model): enhance texture loading with wrapping and filtering parameters

* feat(model): update model loading to support scene-based texture handling and embedded textures

* fix: fix light leak behind objects

* refactor: use assetloader cache for model loading

* chore: change drone model from gltf to glb

* refactor: change material hash in assetloader

* feat(model): enhance model handling with combined mesh generation and draw command struct

* feat(model): refactor model class to use name for unique identification and remove ID_COUNTER

* feat(config): add model config for testing

* fix(config): fix rifle path and add rifle model

* fix(mesh): set default transform to identity matrix in deserialization

* feat(model): replace generateDrawCommands with direct submesh handling in ForwardRenderer

* fix(asset-loader): handle model name correctly

* fix(config): correctly place flashlight of gun

* fix(config): move model to assets key instead of game key

* chore: fix uniform naming in lit.frag for textureMetalnesssRoughness

* fix(litMaterial): initialize TextureMask to zero

* fix(mesh): update bone IDs attribute pointer and return types for vertex and index getters

* perf(ai-glm-utils): add inline specifier to conversion functions for better optimization

* fix(model): update tangent type to vec4 and handle normal mapping in model loading

* fix(model): remove mesh if no material found

* refactor(model): remove incomplete bone data processing implementation

* fix(model): ensure combined mesh is deleted and pointer is reset in destructor

* fix(model): improve tangent and bitangent calculation in OBJ loading

* feat(model): add support for system-installed Assimp

* refactor(forward-renderer):revert changes to render-command header

* fix: update tangent in comibned mesh and fix material memory leak

* chore(material): remove unused function metho declaration

* chore(config): remove unrelated game mesh

* fix: reorder asset-loader include for consistency

Author: AhmedAmrNabil

.gitmodules

@@ -2,11 +2,18 @@
 	path = vendor/glfw
 	url = https://github.com/glfw/glfw.git
 	shallow = true
+
 [submodule "vendor/bullet3"]
 	path = vendor/bullet3
 	url = https://github.com/bulletphysics/bullet3.git
     shallow = true
+
 [submodule "vendor/openal-soft"]
 	path = vendor/openal-soft
 	url = https://github.com/kcat/openal-soft.git
     shallow = true
+
+[submodule "vendor/assimp"]
+	path = vendor/assimp
+	url = https://github.com/assimp/assimp.git
+    shallow = true

CMakeLists.txt

@@ -31,11 +31,13 @@ option(USE_SYSTEM_LIBS "Use system-installed libraries instead of the bundled ve
 option(USE_SYSTEM_OPENAL "Use system-installed OpenAL-Soft instead of the bundled version" $ENV{USE_SYSTEM_OPENAL})
 option(USE_SYSTEM_BULLET "Use system-installed Bullet3 instead of the bundled version" $ENV{USE_SYSTEM_BULLET})
 option(USE_SYSTEM_GLFW "Use system-installed GLFW instead of the bundled version" $ENV{USE_SYSTEM_GLFW})
+option(USE_SYSTEM_ASSIMP "Use system-installed Assimp instead of the bundled version" $ENV{USE_SYSTEM_ASSIMP})
 
 if(USE_SYSTEM_LIBS)
     set(USE_SYSTEM_OPENAL ON CACHE BOOL "" FORCE)
     set(USE_SYSTEM_BULLET ON CACHE BOOL "" FORCE)
     set(USE_SYSTEM_GLFW ON CACHE BOOL "" FORCE)
+    set(USE_SYSTEM_ASSIMP ON CACHE BOOL "" FORCE)
 endif()
 
 # ---- Vendor Libraries ----
@@ -160,6 +162,29 @@ if(USE_VENDOR_OPENAL)
     add_subdirectory(vendor/openal-soft)
 endif()
 
+# ---- Assimp ----
+set(USE_VENDOR_ASSIMP ON CACHE BOOL "" FORCE)
+if(USE_SYSTEM_ASSIMP)
+    find_package(assimp QUIET)
+    if(assimp_FOUND)
+        message(STATUS "Using system-installed Assimp: ${assimp_VERSION}")
+        set(USE_VENDOR_ASSIMP OFF CACHE BOOL "" FORCE)
+    else()
+        message(STATUS "Using bundled Assimp")
+    endif()
+endif()
+
+if(USE_VENDOR_ASSIMP)
+    set(ASSIMP_BUILD_TESTS OFF CACHE BOOL "" FORCE)
+    set(ASSIMP_BUILD_SAMPLES OFF CACHE BOOL "" FORCE)
+    set(ASSIMP_INSTALL OFF CACHE BOOL "" FORCE)
+    set(BUILD_SHARED_LIBS OFF CACHE BOOL "" FORCE)
+    set(ASSIMP_BUILD_ASSIMP_TOOLS OFF CACHE BOOL "" FORCE)
+    set(ASSIMP_BUILD_MINIZIP ON CACHE BOOL "" FORCE)
+    set(ASSIMP_BUILD_ZLIB ON CACHE BOOL "" FORCE)
+    add_subdirectory(vendor/assimp)
+endif()
+
 # ---- GLAD ----
 add_library(glad STATIC
     vendor/glad/src/gl.c
@@ -213,6 +238,8 @@ add_executable(${PROJECT_NAME}
 
     src/common/mesh/mesh-utils.cpp
 
+    src/common/model/model.cpp
+
     src/common/texture/sampler.cpp
     src/common/texture/texture-utils.cpp
     src/common/texture/screenshot.cpp
@@ -226,6 +253,7 @@ add_executable(${PROJECT_NAME}
 
     src/common/components/camera.cpp
     src/common/components/mesh-renderer.cpp
+    src/common/components/model-renderer.cpp
     src/common/components/free-camera-controller.cpp
     src/common/components/movement.cpp
     src/common/components/light.cpp
@@ -264,6 +292,7 @@ target_link_libraries(${PROJECT_NAME}
         BulletCollision
         BulletSoftBody
         LinearMath
+        assimp::assimp
 )
 
 if(USE_SYSTEM_OPENAL AND OpenAL_FOUND)
@@ -278,6 +307,13 @@ else()
     )
 endif()
 
+if(USE_SYSTEM_ASSIMP AND assimp_FOUND)
+    target_include_directories(${PROJECT_NAME}
+        PRIVATE
+            ${assimp_INCLUDE_DIRS}
+    )
+endif()
+
 target_compile_definitions(${PROJECT_NAME}
     PRIVATE
         $<$<CONFIG:Debug>:COLLISION_DEBUG_DRAW>

assets/gltf/mech_drone/mech_drone.glb

@@ -37,6 +37,9 @@ struct Material {
 
     sampler2D textureEmissive;
     bool hasTextureEmissive;
+
+    sampler2D hasTextureMetalnessRoughness;
+    bool hasMetalnessRoughness;
 };
 uniform Material material;
 uniform float alphaThreshold;
@@ -69,19 +72,29 @@ vec3 sampleAlbedo(vec2 uv) {
 }
 
 float sampleMetallic(vec2 uv) {
-    return material.hasTextureMetallic ? texture(material.textureMetallic, uv).r * material.metallic : material.metallic;
+    if(material.hasMetalnessRoughness)
+        return texture(material.hasTextureMetalnessRoughness, uv).b * material.metallic; // B channel
+    if(material.hasTextureMetallic)
+        return texture(material.textureMetallic, uv).r * material.metallic;
+    return material.metallic;
 }
 
 float sampleRoughness(vec2 uv) {
-    return material.hasTextureRoughness ? texture(material.textureRoughness, uv).r * material.roughness : material.roughness;
+    if(material.hasMetalnessRoughness)
+        return texture(material.hasTextureMetalnessRoughness, uv).g * material.roughness; // G channel
+    if(material.hasTextureRoughness)
+        return texture(material.textureRoughness, uv).r * material.roughness;
+    return material.roughness;
 }
 
 float sampleAO(vec2 uv) {
     return material.hasTextureAmbientOcclusion ? texture(material.textureAmbientOcclusion, uv).r * material.ambientOcclusion : material.ambientOcclusion;
 }
 
 vec3 sampleEmission(vec2 uv) {
-    return material.hasTextureEmissive ? texture(material.textureEmissive, uv).rgb * material.emission : material.emission;
+    if(material.hasTextureEmissive)
+        return texture(material.textureEmissive, uv).rgb; // texture owns the color
+    return material.emission; // factor only when no texture
 }
 
 vec3 sampleNormal(vec2 uv) {
@@ -111,6 +124,9 @@ vec3 calcLight(
         vec3 toLight = light.position - fs_in.worldPos;
         float dist = length(toLight);
         L = normalize(toLight);
+        if(dot(toLight, N) <= 0.0) {
+            return vec3(0.0);
+        }
 
         // quadratic attenuation: 1 / (c + l*d + q*d^2)
         attenuation = 1.0 / (light.attenuation.x + light.attenuation.y * dist + light.attenuation.z * dist * dist);

assets/gltf/weapons/rifle.glb

@@ -4,7 +4,9 @@ layout(location = 0) in vec3 position;
 layout(location = 1) in vec4 color;
 layout(location = 2) in vec2 tex_coord;
 layout(location = 3) in vec3 normal;
-layout(location = 4) in vec3 tangent;
+layout(location = 4) in vec4 tangent;
+layout(location = 5) in ivec4 bone_ids;
+layout(location = 6) in vec4 weights;
 
 out Varyings {
     vec4 color;
@@ -30,8 +32,8 @@ void main() {
     vs_out.worldNormal = N;
 
     // TBN matrix for normal mapping
-    vec3 T = normalize(normalMatrix * tangent);
+    vec3 T = normalize(normalMatrix * tangent.xyz);
     T = normalize(T - dot(T, N) * N);  // re-orthogonalize
-    vec3 B = cross(N, T);
+    vec3 B = cross(N, T) * tangent.w;  // bitangent with handedness
     vs_out.TBN = mat3(T, B, N);
 }

assets/shaders/lit.frag

@@ -177,6 +177,9 @@
                     "texture": "moon",
                     "sampler": "default"
                 }
+            },
+            "models": {
+                "drone": "assets/gltf/mech_drone/mech_drone.glb"
             }
         },
         "game": {