Work on animation subsystem

- Also incomplete refactor of inline functions

8 files changed, 110 insertions, 40 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2c5dd35..343273c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -14,6 +14,7 @@ add_executable(game
     "include/player.h"
     "include/assets.h"
     "include/background.h"
+    "include/utils.h"
     
     "src/game.c"
     "src/main.c"
diff --git a/include/constants.h b/include/constants.h
index 870c7fb..2fd6ace 100644
--- a/include/constants.h
+++ b/include/constants.h
@@ -9,3 +9,6 @@
 #define MAX_SPRITE_COUNT 4 //Maximum number of sprites per entity
 
 #define NO_OFFSET 0
+
+#define MAX_FRAMES 30
+#define MAX_ANIMATIONS 20
diff --git a/include/game.h b/include/game.h
index e54afd3..530ae73 100644
--- a/include/game.h
+++ b/include/game.h
@@ -21,10 +21,25 @@ typedef enum DrawLayer {
     Foreground_Layer = 1
 } DrawLayer;
 
+typedef struct Animation {
+    int numFrames;
+    bool isLooping;
+    bool isComplete;
+    Rectangle srcRects[MAX_FRAMES];
+    float frameTimes[MAX_FRAMES];
+
+    int currentFrame;
+    float currentFrameTimer;
+} Animation;
+
 typedef struct Sprite {
     Texture2D texture;
     DrawLayer layer;
     Rectangle destRect; //Destination rectangle relative to player position
+
+    int numAnimations; //Zero for static spritesx
+    Animation animations[MAX_ANIMATIONS];
+    int currentAnimation;
 } Sprite;
 
 typedef struct Entity {
@@ -69,20 +84,8 @@ void InitGame();
 void UpdateGame(float deltaTime);
 void DrawGame();
 
-static inline bool EntityAllocated(const Entity* e) {
-    return (e->flags & ENTITY_ALLOCATED);
-}
-
-static inline bool SameEntity(const Entity* a, const Entity* b) {
-    return a->id == b->id;
-}
-
-static inline void AddSpriteToEntity(Entity* e, Sprite s) {
-    if (e->numSprites < MAX_SPRITE_COUNT) {
-        e->sprites[e->numSprites++] = s;
-    }
-}
-
+void UpdateCurrentSpriteAnimation(Sprite* sprite, float dt);
+void DrawEntitySprite(const Sprite* sprite, int spriteIndex);
 
 #ifdef BEATEMUP_DEBUG
 void DebugHighlights(const Entity* e);
diff --git a/include/utils.h b/include/utils.h
new file mode 100644
index 0000000..59c1bc4
--- /dev/null
+++ b/include/utils.h
@@ -0,0 +1,55 @@
+#ifndef UTILS_H_
+#define UTILS_H_
+
+#include <stdbool.h>
+#include "game.h"
+
+static inline bool EntityAllocated(const Entity* e) {
+    return (e->flags & ENTITY_ALLOCATED);
+}
+
+static inline bool PhysicsEnabled(const Entity* e) {
+    return EntityAllocated(e) && (e->flags & ENTITY_PHYSICS_ACTIVE);
+}
+
+static inline bool SameEntity(const Entity* a, const Entity* b) {
+    return a->id == b->id;
+}
+
+static inline void AddSpriteToEntity(Entity* e, Sprite s) {
+    if (e->numSprites < MAX_SPRITE_COUNT) {
+        e->sprites[e->numSprites++] = s;
+    }
+}
+
+static inline bool IsAnimated(const Sprite* s) {
+  return s->numAnimations > 0;
+}
+
+static inline bool ShouldDrawEntity(const Entity* e, DrawLayer layerDrawing) {
+    return EntityAllocated(e)
+        && (e->flags & ENTITY_VISIBLE);
+}
+
+static inline Rectangle GetSpriteDrawDestinationRectGlobal(const Entity* e, int spriteIndex) {
+    Rectangle destRectGlobal = e->sprites[spriteIndex].destRect;
+
+    destRectGlobal.x += e->position.x;
+    destRectGlobal.y += e->position.y;
+
+    return destRectGlobal;
+}
+
+static inline Rectangle GetPhysicsColliderGlobal(const Entity* e) {
+    Rectangle physicsColliderGlobal = e->physicsCollider;
+    physicsColliderGlobal.x += e->position.x;
+    physicsColliderGlobal.y += e->position.y;
+
+    return physicsColliderGlobal;
+}
+
+static inline Animation* GetCurrentAnimation(Sprite* s) {
+    return &s->animations[s->currentAnimation];
+}
+
+#endif // UTILS_H_
diff --git a/src/background.c b/src/background.c
index d3588a7..c9ed1fb 100644
--- a/src/background.c
+++ b/src/background.c
@@ -3,6 +3,7 @@
 #include <raymath.h>
 #include <assert.h>
 #include <stdlib.h>
+#include "utils.h"
 
 void AddBackground(const char* backgroundTextureName) {
   Entity e = {0};
diff --git a/src/game.c b/src/game.c
index 55b65c2..8659939 100644
--- a/src/game.c
+++ b/src/game.c
@@ -8,23 +8,10 @@
 #include "player.h"
 #include "background.h"
 #include <math.h>
+#include "utils.h"
 
 Game game;
 
-static inline bool ShouldDrawEntity(const Entity* e, DrawLayer layerDrawing) {
-    return EntityAllocated(e)
-        && (e->flags & ENTITY_VISIBLE);
-}
-
-static inline Rectangle GetSpriteDrawDestinationRectGlobal(const Entity* e, int spriteIndex) {
-    Rectangle destRectGlobal = e->sprites[spriteIndex].destRect;
-
-    destRectGlobal.x += e->position.x;
-    destRectGlobal.y += e->position.y;
-
-    return destRectGlobal;
-}
-
 void AddEntity(Entity* e) {
     static int nextId = 0;
 
@@ -158,3 +145,33 @@ void AddWall(float xpos, float ypos, float width, float height) {
     
     AddEntity(&wall);
 }
+
+static inline float GetCurrentFrameTime(const Animation* animation) {
+    return animation->frameTimes[animation->currentFrame];
+}
+
+void UpdateCurrentSpriteAnimation(Sprite* sprite, float dt) {
+    if (!IsAnimated(sprite))
+        return;
+
+    Animation* currentAnimation = GetCurrentAnimation(sprite);
+
+    if (currentAnimation->isComplete)
+        return;
+
+    currentAnimation->currentFrameTimer += dt;
+
+    if (currentAnimation->currentFrameTimer >= GetCurrentFrameTime(currentAnimation)) {
+        currentAnimation->currentFrame++;
+        currentAnimation->currentFrameTimer = 0;
+    }
+
+    if (currentAnimation->currentFrame >= currentAnimation->numFrames) {
+        if (currentAnimation->isLooping)
+            currentAnimation->currentFrame = 0;
+        else {
+            currentAnimation->currentFrame = currentAnimation->numFrames - 1;
+            currentAnimation->isComplete = true;
+        }
+    }
+}
diff --git a/src/physics.c b/src/physics.c
index 51e80f5..bc93a29 100644
--- a/src/physics.c
+++ b/src/physics.c
@@ -1,20 +1,9 @@
 #include "physics.h"
 #include "game.h"
+#include "utils.h"
 
 extern Game game;
 
-static inline bool PhysicsEnabled(const Entity* e) {
-    return EntityAllocated(e) && (e->flags & ENTITY_PHYSICS_ACTIVE);
-}
-
-static inline Rectangle GetPhysicsColliderGlobal(const Entity* e) {
-    Rectangle physicsColliderGlobal = e->physicsCollider;
-    physicsColliderGlobal.x += e->position.x;
-    physicsColliderGlobal.y += e->position.y;
-
-    return physicsColliderGlobal;
-}
-
 void MoveAndSlide(Entity* e, float deltaTime) {
     Vector2 velocity = e->velocity;
     Rectangle physicsCollider = GetPhysicsColliderGlobal(e);
diff --git a/src/player.c b/src/player.c
index 67f971f..62675f4 100644
--- a/src/player.c
+++ b/src/player.c
@@ -5,6 +5,7 @@
 #include "player.h"
 #include "physics.h"
 #include "assets.h"
+#include "utils.h"
 
 extern Game game;