Refactoring.

Author: Flone-dnb

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "ext/SDL"]
 	path = ext/SDL
 	url = https://github.com/libsdl-org/SDL.git
+[submodule "ext/cglm"]
+	path = ext/cglm
+	url = https://github.com/recp/cglm.git

CMakeLists.txt

@@ -48,7 +48,7 @@ function(tiny_engine_configure_target TARGET_NAME)
     if(MSVC)
         target_compile_options(${TARGET_NAME} PUBLIC /W3 /WX)
     else()
-        target_compile_options(${TARGET_NAME} PUBLIC -Wall -Wextra -Werror -Wconversion)
+        target_compile_options(${TARGET_NAME} PUBLIC -Wall -Wextra -Werror -Wconversion -Wno-unused-but-set-parameter)
     endif()
 
     # Add includes (relative to the target's directory).

ext/cglm

@@ -16,6 +16,9 @@ set(PROJECT_SOURCES
     src/renderer.c
     src/world.c
     src/ecs/ecs.c
+    src/ecs/transform_component.c
+    src/ecs/camera_component.c
+    src/ecs/camera_system.c
     include/window.h
     include/io/log.h
     include/io/paths.h
@@ -26,6 +29,9 @@ set(PROJECT_SOURCES
     include/renderer.h
     include/world.h
     include/ecs/ecs.h
+    include/ecs/transform_component.h
+    include/ecs/camera_component.h
+    include/ecs/camera_system.h
 )
 
 # Define targets (one without any specific macros and another for compilation with editor).
@@ -79,6 +85,16 @@ target_include_directories(${GLAD_TARGET_NAME} SYSTEM PUBLIC ${RELATIVE_EXT_PATH
 target_link_libraries(${ENGINE_LIB_DEPS_TARGET} INTERFACE ${GLAD_TARGET_NAME})
 add_dependencies(${ENGINE_LIB_DEPS_TARGET} ${GLAD_TARGET_NAME})
 
+# Add cglm.
+message(STATUS "${PROJECT_NAME}: adding dependency \"cglm\"...")
+set(CGLM_SHARED OFF CACHE BOOL "" FORCE)
+set(CGLM_STATIC ON CACHE BOOL "" FORCE)
+set(CGLM_USE_C99 ON CACHE BOOL "" FORCE)
+set(CGLM_USE_TEST OFF CACHE BOOL "" FORCE)
+add_subdirectory(${RELATIVE_EXT_PATH}/cglm ${DEPENDENCY_BUILD_DIR_NAME}/cglm EXCLUDE_FROM_ALL)
+target_link_libraries(${ENGINE_LIB_DEPS_TARGET} INTERFACE cglm_headers)
+target_compile_definitions(cglm_headers INTERFACE CGLM_ALL_UNALIGNED)
+
 # Link engine library to dependencies.
 target_link_libraries(${ENGINE_LIB_TARGET} PUBLIC ${ENGINE_LIB_DEPS_TARGET})
 target_link_libraries(${ENGINE_LIB_TARGET_FOR_EDITOR} PUBLIC ${ENGINE_LIB_DEPS_TARGET})

src/engine_lib/CMakeLists.txt

@@ -0,0 +1,95 @@
+#pragma once
+
+#include <stdbool.h>
+#include "cglm/cglm.h"
+
+/** Manages camera properties. */
+struct te_camera_component;
+
+/**
+ * Sets camera's near clip plane distance.
+ *
+ * @param comp Component.
+ * @param z    Non-negative value.
+ */
+void camera_set_near_clip(struct te_camera_component* comp, float z);
+
+/**
+ * Sets camera's far clip plane distance.
+ *
+ * @param comp Component.
+ * @param z Non-negative value.
+ */
+void camera_set_far_clip(struct te_camera_component* comp, float z);
+
+/**
+ * Sets camera's vertical field of view.
+ *
+ * @param comp Component.
+ * @param fov  Vertical FOV.
+ */
+void camera_set_vertical_fov(struct te_camera_component* comp, unsigned char fov);
+
+/**
+ * Returns camera's near clip plane distance.
+ *
+ * @param comp Component.
+ *
+ * @return Near clip.
+ */
+float camera_get_near_clip(struct te_camera_component* comp);
+
+/**
+ * Returns camera's far clip plane distance.
+ *
+ * @param comp Component.
+ *
+ * @return Far clip.
+ */
+float camera_get_far_clip(struct te_camera_component* comp);
+
+/**
+ * Returns camera's vertical field of view.
+ *
+ * @return Vertical FOV.
+ */
+unsigned char camera_get_vertical_fov(struct te_camera_component* comp);
+
+// ------------------------------------------------------------------------------------------------
+//                                       PRIVATE API
+// ------------------------------------------------------------------------------------------------
+
+/**
+ * Returns sizeof(te_camera_component).
+ *
+ * @return Size in bytes.
+ */
+unsigned int prv_camera_component_get_sizeof(void);
+
+/**
+ * Initializes allocated memory.
+ *
+ * @param data Allocated component data.
+ */
+void prv_camera_component_init(void* data);
+
+/**
+ * Returns `true` if some properties of the camera changed
+ * and view and projection matrices need to be recalculated.
+ *
+ * @remark This function is used by the camera system.
+ *
+ * @param comp Component.
+ *
+ * @return `true` if changed.
+ */
+bool prv_camera_is_properties_changed(struct te_camera_component* comp);
+
+/**
+ * Sets `false` to @ref prv_camera_is_properties_changed.
+ *
+ * @remark This function is used by the camera system.
+ *
+ * @param comp Component.
+ */
+void prv_camera_reset_properties_changed_flag(struct te_camera_component* comp);

src/engine_lib/include/ecs/camera_component.h

@@ -0,0 +1,63 @@
+#pragma once
+
+#include <stdbool.h>
+#include "cglm/cglm.h"
+
+/** Manages camera components. */
+struct te_camera_system;
+
+/**
+ * Sets ID of an entity (with a camera component) that should be the active camera
+ * (the camera used to render the world).
+ *
+ * @param system    Camera system.
+ * @param entity_id ID of an entity to be the active camera.
+ */
+void camera_system_set_active_camera(struct te_camera_system* system, unsigned int entity_id);
+
+/**
+ * Returns `true` if there is an active camera to render the world.
+ *
+ * @param system Camera system.
+ *
+ * @return `true` if have active camera.
+ */
+bool camera_system_is_camera_set(struct te_camera_system* system);
+
+/**
+ * Returns active camera's view matrix.
+ *
+ * @param system Camera system.
+ * @param out    Output.
+ */
+void camera_system_get_camera_view(struct te_camera_system* system, mat4 out);
+
+/**
+ * Returns active camera's projection matrix.
+ *
+ * @param system Camera system.
+ * @param out    Output.
+ */
+void camera_system_get_camera_proj(struct te_camera_system* system, mat4 out);
+
+// ------------------------------------------------------------------------------------------------
+//                                       PRIVATE API
+// ------------------------------------------------------------------------------------------------
+
+struct te_ecs;
+
+/**
+ * Creates a new camera system to manage entities with camera components.
+ *
+ * @param ecs ECS manager. The pointer must be valid while the system exists.
+ *
+ * @return Camera system.
+ */
+struct te_camera_system* prv_camera_system_create(struct te_ecs* ecs);
+
+/**
+ * Destroys a camera system.
+ *
+ * @param system System.
+ */
+void prv_camera_system_destroy(struct te_camera_system* system);

src/engine_lib/include/ecs/camera_system.h

@@ -8,10 +8,11 @@ typedef struct te_ecs te_ecs;
 
 /** Engine component type IDs. */
 enum te_ecs_engine_component_type_id : unsigned int {
-    ECS_COMPONENT_TYPE_TRANSFORM = 0,
+    TE_ECS_COMPONENT_TYPE_TRANSFORM = 0,
+    TE_ECS_COMPONENT_TYPE_CAMERA,
     // ... new engine component types go here ...
 
-    ECS_COMPONENT_TYPE_FIRST_GAME_COMPONENT, // <- first component type ID for games
+    TE_ECS_COMPONENT_TYPE_FIRST_GAME_COMPONENT, // <- first component type ID for games
 };
 
 /**
@@ -95,13 +96,10 @@ void ecs_unregister_system(te_ecs* ecs, void* user_system);
  * @param component_type_ids Non-NULL pointer to type IDs of the components that the entity has
  * (component types must be previously registered using @ref ecs_register_component_type).
  *
- * @param opt_parent_entity_id Specify TE_ECS_ENTITY_ID_INVALID if the newly entity is not a child of some other entity,
- * otherwise specify a valid ID of an existing entity.
- *
  * @return Unique ID of the created entity.
  */
 unsigned int ecs_create_entity(te_ecs* ecs, const char* name, unsigned int component_count,
-                               unsigned int* component_type_ids, unsigned int opt_parent_entity_id);
+                               unsigned int* component_type_ids);
 
 /**
  * Destroys an entity that was previously created using @ref ecs_create_entity.
@@ -171,18 +169,6 @@ void* ecs_get_entity_component(te_ecs* ecs, unsigned int entity_id, unsigned int
  */
 const char* ecs_get_entity_name(te_ecs* ecs, unsigned int entity_id);
 
-/**
- * Returns TE_ECS_ENTITY_ID_INVALID if the entity does not have a parent entity, otherwise 
- * returns entity ID of the parent entity.
- *
- * @param ecs ECS manager.
- *
- * @param entity_id ID of the entity.
- *
- * @return TE_ECS_ENTITY_ID_INVALID if no parent.
- */
-unsigned int ecs_get_entity_parent(te_ecs* ecs, unsigned int entity_id);
-
 // ------------------------------------------------------------------------------------------------
 //                                       PRIVATE API
 // ------------------------------------------------------------------------------------------------

src/engine_lib/include/ecs/ecs.h

@@ -0,0 +1,80 @@
+#pragma once
+
+#include "cglm/cglm.h"
+
+/** Allows entities to have a specific location, rotation and size in the world. */
+struct te_transform_component;
+
+/**
+ * Sets location.
+ *
+ * @param comp Component data.
+ * @param in   Value to set.
+ */
+void transform_set_location(struct te_transform_component* comp, vec3 in);
+
+/**
+ * Sets rotation in degrees.
+ *
+ * @param comp Component data.
+ * @param in   Value to set.
+ */
+void transform_set_rotation(struct te_transform_component* comp, vec3 in);
+
+/**
+ * Sets scale.
+ *
+ * @param comp Component data.
+ * @param in   Value to set.
+ */
+void transform_set_scale(struct te_transform_component* comp, vec3 in);
+
+/**
+ * Returns location.
+ *
+ * @param comp Component data.
+ * @param out  Value to write the result to.
+ */
+void transform_get_location(struct te_transform_component* comp, vec3 out);
+
+/**
+ * Returns rotation in radians.
+ *
+ * @param comp Component data.
+ * @param out  Value to write the result to.
+ */
+void transform_get_rotation(struct te_transform_component* comp, vec3 out);
+
+/**
+ * Returns scale.
+ *
+ * @param comp Component data.
+ * @param out  Value to write the result to.
+ */
+void transform_get_scale(struct te_transform_component* comp, vec3 out);
+
+/**
+ * Returns normalized forward direction.
+ *
+ * @param comp Component data.
+ * @param out  Value to write the result to. 4th component is zero.
+ */
+void transform_get_forward(struct te_transform_component* comp, vec4 out);
+
+// ------------------------------------------------------------------------------------------------
+//                                       PRIVATE API
+// ------------------------------------------------------------------------------------------------
+
+/**
+ * Returns sizeof(te_transform_component).
+ *
+ * @return Size in bytes.
+ */
+unsigned int prv_transform_component_get_sizeof(void);
+
+/**
+ * Initializes allocated memory.
+ *
+ * @param data Allocated component data.
+ */
+void prv_transform_component_init(void* data);

src/engine_lib/include/ecs/transform_component.h

@@ -6,3 +6,24 @@
  * @return Application name.
  */
 const char* globals_get_app_name(void);
+
+/**
+ * Returns a normalized vector that points in the world's forward direction.
+ *
+ * @param out Value to write the result to. 4th component is zero.
+ */
+void globals_get_world_forward(float out[4]);
+
+/**
+ * Returns a normalized vector that points in the world's right direction.
+ *
+ * @param out Value to write the result to. 4th component is zero.
+ */
+void globals_get_world_right(float out[4]);
+
+/**
+ * Returns a normalized vector that points in the world's up direction.
+ *
+ * @param out Value to write the result to. 4th component is zero.
+ */
+void globals_get_world_up(float out[4]);