collision/more physics updates

src/collision.c

@@ -3,34 +3,42 @@
 #include "config.h"
 #include "collision.h"
 #include "player.h"
-
+#include <stdio.h>
 void checkCollision(){
     for(int u=0; u<=MAX_ENTITIES-1; u++){
         Entity *en1 = &entities[u];
         if(!en1->active){ 
         continue;
         }
+        en1->headgrounded = false;
         for(int j=u+1; j<=MAX_ENTITIES-1; j++){
             if(u!=j){
                 Entity *en2 = &entities[j];
                 if(!en2->active){ 
                 continue;
                 }
-                if (fabsf(en1->position.x - en2->position.x) < (en1->size * 0.5f + en2->size * 0.5f) && fabsf(en1->position.y - en2->position.y) < (en1->size * 0.5f + en2->size * 0.5f))
+                printf("%d\n", en1->headgrounded);
+                
+                float half = (en1->size + en2->size) * 0.5f;
+                float overlapX = half - fabsf(en1->position.x - en2->position.x);
+                float overlapY = half - fabsf(en1->position.y - en2->position.y);
+
+                if (overlapX > 0 && overlapY > 0)
                 {
-                        
-                        float forcex=fabsf(((en1->mass+en2->mass)/2)*((((en1->velocity.x)+(scale))+((en2->velocity.x)+(scale)))/2))*(scale);
+                    if (overlapY < overlapX && en1->position.y < en2->position.y)
+                    {
+                        // top collision
+                        en1->position.y = en2->position.y - half;
+                        en1->velocity.y = 0;
+                        en1->velocity.x *= en2->drag;
+                        en1->headgrounded = true;
+                    } else {
+                        en1->headgrounded = false;
+                        float forcex=fabsf(((en1->mass+en2->mass)/2)*((((en1->velocity.x)+(scale))+((en2->velocity.x)+(scale)))/2))*(scale*1.5);
                         float forcey=fabsf(((en1->mass+en2->mass)/2)*((((en1->velocity.y)+(scale))+((en2->velocity.y)+(scale)))/2))*(scale/4);
-                    if(en1->position.y+en1->size*0.6f <= en2->position.y+en2->size*0.5f){
-                            ApplyForce(
-                                en1,
-                                (Vector2){0, -((en1->mass*g))}
-                            );
-                            en1->velocity.y = en1->velocity.y * 0.1f;
-                            en1->velocity.x = en1->velocity.x * en2->drag;
-                    }
-                    else if(en1->position.x < en2->position.x){
-                        
+                 if(en1->position.x < en2->position.x){
+                        en1->velocity.x=0;
+                        en2->velocity.x=0;
                         ApplyForce(
                             en1,
                             (Vector2){-forcex, 0}
@@ -41,6 +49,8 @@ void checkCollision(){
                         );
                     }
                     else{
+                        en1->velocity.x=0;
+                        en2->velocity.x=0;
                         ApplyForce(
                             en1,
                             (Vector2){forcex, 0}
@@ -54,4 +64,5 @@ void checkCollision(){
                 }
             }
         }
+    } 
 }

src/entity.h

@@ -10,6 +10,7 @@ typedef struct Entity
 
     bool isPlayer;
     bool affectedByGravity;
+    bool headgrounded;
 
     float mass;
     float size;

src/physics.c

@@ -21,7 +21,7 @@ void UpdateEntities(float dt, int screenWidth)
         bool onGround = IsGrounded(e);
 
         // Apply gravity force if enabled for this entity
-        if (e->affectedByGravity)
+        if (e->affectedByGravity && !onGround)
         {
             ApplyForce(
                 e,

src/world.c

@@ -1,5 +1,6 @@
 #include <stddef.h>
 #include "world.h"
+#include "collision.h"
 
 // the beeg one. hooooooooooooooooh boy
 
@@ -39,12 +40,12 @@ bool IsGrounded(Entity *e)
 {
     if (!e)
         return false;
-
-    return (
-        e->position.y +
-        e->size * 0.5f >=
-        ground_y - 2.0f
-    );
+    if(e->position.y +e->size * 0.5f >=ground_y - 2.0f || e->headgrounded){
+        return true;
+    }
+    else{
+        return false;
+    }
 }
 
 Entity *SpawnEntity(
@@ -76,6 +77,7 @@ Entity *SpawnEntity(
             e->force = (Vector2){0, 0};
 
             e->color = color;
+            e->headgrounded = false;
 
             return e;
         }