Add shearing function

include/header.h

@@ -75,6 +75,7 @@ void move(struct kinematic_obj *obj, Vector2 acceleration);
 void set_position(struct kinematic_obj *obj, int x, int y);
 bool place_meeting(struct kinematic_obj *obj, Vector2 dir);
 void scale_rect(struct kinematic_obj *obj);
+void adjust_hitbox(struct kinematic_obj *obj);
 
 // Math functions, math.c
 long mag(Vector2 vec);

obj/kinematics.c

@@ -27,13 +27,17 @@ void move(struct kinematic_obj *obj, Vector2 acceleration){
 
     Rectangle collide_rect;
     struct kinematic_obj_node *current;
-    //Simplistic Collision Handling for AABB, Could add coeff of restitution?
-    // TODO: Dont reset velocity if clipping vector is not the same dir as the movement dir
+    // Simplistic Collision Handling for AABB, Could add coeff of restitution?
+    // TODO: Implement the slightly better method of collision from:
+    // https://hopefultoad.blogspot.com/2017/09/2d-aabb-collision-detection-and-response.html
+
+    // Also think about what happens if the square is completely inside the shape
+    // Then extend to multiple object
+    // Might need to check distance
     obj->velocity.x += acceleration.x * delta;
     obj->pos.x += obj->velocity.x * delta;
     obj->rect.x = obj->pos.x + obj->dim_reduction[0];
     obj->rect.width = obj->ori_width - obj->dim_reduction[0]  - obj->dim_reduction[2];
-
     current = kinematic_HEAD;
     while(current != NULL){
         if(current->obj != obj){
@@ -112,3 +116,10 @@ Vector2 center(Rectangle rect){
         .y = rect.y + rect.height/2
     };
 }
+
+void adjust_hitbox(struct kinematic_obj *obj){
+    approach(&obj->dim_reduction[0], obj->set_dim_reduction[0], 0.2);
+    approach(&obj->dim_reduction[1], obj->set_dim_reduction[1], 0.2);
+    approach(&obj->dim_reduction[2], obj->set_dim_reduction[2], 0.2);
+    approach(&obj->dim_reduction[3], obj->set_dim_reduction[3], 0.2);
+}

obj/player.c

@@ -127,8 +127,8 @@ void player_input_check(struct player_obj *player){
             set_squish_target_offset(player->image, 1, 0);
             if(frame_counter<land_lag_frames){
                     ++frame_counter;
-                if (IsKeyDown(JUMP))
-                    state_buffer = JUMP_SQUAT;
+                //if (IsKeyDown(JUMP))
+                //    state_buffer = JUMP_SQUAT;
             }                              
             else{
                 jumps = 1;
@@ -155,12 +155,7 @@ void player_input_check(struct player_obj *player){
     }
 
     // Set the hitbox reductions
-    approach(&player->kinematic.dim_reduction[0], player->kinematic.set_dim_reduction[0], 0.2);
-    approach(&player->kinematic.dim_reduction[1], player->kinematic.set_dim_reduction[1], 0.2);
-    approach(&player->kinematic.dim_reduction[2], player->kinematic.set_dim_reduction[2], 0.2);
-    approach(&player->kinematic.dim_reduction[3], player->kinematic.set_dim_reduction[3], 0.2);
-
-    //scale_rect(&player->kinematic);
+    adjust_hitbox(&player->kinematic);
 
     if (IsKeyPressed(JUMP) && jumps > 0){
         player->state = JUMP_SQUAT;
@@ -187,4 +182,26 @@ void player_input_check(struct player_obj *player){
     }
 
     move(&player->kinematic, accel);
+
+    //Skidding
+    if (on_ground == true){
+        if (IsKeyDown(LEFT)){
+            if (player->kinematic.velocity.x > 0){
+                set_squish_target_offset(player->image, 0, 15);
+                player->kinematic.dim_reduction[0] = 10;
+            }else{
+                set_squish_target_offset(player->image, 0, 0);
+                player->kinematic.dim_reduction[0] = 0;
+            }
+        }
+        else if(IsKeyDown(RIGHT)){
+            if (player->kinematic.velocity.x < 0){
+                set_squish_target_offset(player->image, 2, 15);
+                player->kinematic.dim_reduction[2] = 10;
+            }else{
+                set_squish_target_offset(player->image, 2, 0);
+                player->kinematic.dim_reduction[2] = 0;
+            }
+        }
+    }
 }

obj/squishy.c

@@ -4,6 +4,16 @@
 #define INTERP_FACTOR 0.2
 #define OFFSET_VALUE 20
 
+float shear_mat[16] =  {1.0, 0.0, 0, 0,
+                        0.1, 1.0, 0, 0,
+                        0, 0, 1.0, 0,
+                        0, 0, 0, 1.0};
+
+float translate_mat[16] =  {1,0,0,0,
+                            0,1,0,0,
+                            0,0,1,0,
+                            0,0,0,1};
+
 void three_point_beizer(Vector2 start, Vector2 mid, Vector2 end, Vector2* arr);
 void calc_offsets(struct squishy_square *square);
 
@@ -112,10 +122,12 @@ void calc_offsets(struct squishy_square *square){
 
 void draw_squishy(struct squishy_square *square){
     rlPushMatrix();
-        rlTranslatef(square->center.x, square->center.y, 0.0f);
-        //rlTranslatef(0.0f, square->parent->rect.height/2, 0.0f);
-        //rlScalef(0.5, 0.5, 1.0);
-        //rlTranslatef(0.0f, -square->parent->rect.height/2, 0.0f);
+        // TODO: Need a correction term to put the square in the box????
+        rlMultMatrixf(shear_mat);
+        translate_mat[12] = square->center.x;
+        translate_mat[13] = square->center.y;
+        rlMultMatrixf(translate_mat);
+
         int i;
         for(i=0;i<BEZIER_POINTS;++i){
             DrawTriangle(square->top_vertices[i], (Vector2){0,0}, square->top_vertices[i+1], square->color);