deleted as no longer used modified accordingly

2008-02-27  Jim Huang  <jserv.tw@gmail.com>

        * src/core/spring-model.[ch]: deleted as no longer used
        * src/Makefile.am: modified accordingly

svn path=/trunk/; revision=3607

4 files changed, 4 insertions, 453 deletions

diff --git a/ChangeLog b/ChangeLog
index ee497655..08a76776 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2008-02-27  Jim Huang  <jserv.tw@gmail.com>
+
+        * src/core/spring-model.[ch]: deleted as no longer used
+        * src/Makefile.am: modified accordingly
 2008-02-27  Thomas Thurman  <tthurman@gnome.org>
 
 	Lots of tiny fixes to make sure we compile with
diff --git a/src/Makefile.am b/src/Makefile.am
index 359a8540..32e23a98 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -53,8 +53,6 @@ metacity_SOURCES= 				\
 	core/screen.h				\
 	core/session.c				\
 	core/session.h				\
-	core/spring-model.c			\
-	core/spring-model.h			\
 	core/stack.c				\
 	core/stack.h				\
 	core/util.c				\
diff --git a/src/core/spring-model.c b/src/core/spring-model.c
deleted file mode 100644
index 60e2ad88..00000000
--- a/src/core/spring-model.c
+++ /dev/null
@@ -1,418 +0,0 @@
-/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
-
-#include "spring-model.h"
-#include <math.h>
-
-struct XYPair
-{
-  double x, y;
-};
-
-#define GRID_WIDTH  4
-#define GRID_HEIGHT 4
-
-#define MODEL_MAX_OBJECTS (GRID_WIDTH * GRID_HEIGHT)
-#define MODEL_MAX_SPRINGS (MODEL_MAX_OBJECTS * 2)
-
-#define DEFAULT_SPRING_K  5.0
-#define DEFAULT_FRICTION  1.4
-
-struct Spring {
-  Object *a;
-  Object *b;
-  /* Spring position at rest, from a to b:
-     offset = b.position - a.position
-  */
-  Vector offset;
-};
-
-struct Object {
-  Vector force;
-  
-  Point position;
-  Vector velocity;
-  
-  double mass;
-  double theta;
-  
-  int immobile;
-};
-
-struct Model {
-  int num_objects;
-  Object objects[MODEL_MAX_OBJECTS];
-  
-  int num_springs;
-  Spring springs[MODEL_MAX_SPRINGS];
-  
-  Object *anchor_object;
-  Vector anchor_offset;
-  
-  double friction;/* Friction constant */
-  double k;/* Spring constant */
-  
-  double last_time;
-  double steps;
-};
-
-static void
-object_init (Object *object,
-	     double position_x, double position_y,
-	     double velocity_x, double velocity_y, double mass)
-{
-  object->position.x = position_x;
-  object->position.y = position_y;
-  
-  object->velocity.x = velocity_x;
-  object->velocity.y = velocity_y;
-  
-  object->mass = mass;
-  
-  object->force.x = 0;
-  object->force.y = 0;
-  
-  object->immobile = 0;
-}
-
-static void
-spring_init (Spring *spring,
-	     Object *object_a, Object *object_b,
-	     double offset_x, double offset_y)
-{
-  spring->a = object_a;
-  spring->b = object_b;
-  spring->offset.x = offset_x;
-  spring->offset.y = offset_y;
-}
-
-static void
-model_add_spring (Model *model,
-		  Object *object_a, Object *object_b,
-		  double offset_x, double offset_y)
-{
-  Spring *spring;
-  
-  g_assert (model->num_springs < MODEL_MAX_SPRINGS);
-  
-  spring = &model->springs[model->num_springs];
-  model->num_springs++;
-  
-  spring_init (spring, object_a, object_b, offset_x, offset_y);
-}
-
-static void
-object_apply_force (Object *object, double fx, double fy)
-{
-  object->force.x += fx;
-  object->force.y += fy;
-}
-
-/* The model here can be understood as a rigid body of the spring's
- * rest shape, centered on the vector between the two object
- * positions. This rigid body is then connected by linear-force
- * springs to each object. This model does degnerate into a simple
- * spring for linear displacements, and does something reasonable for
- * rotation.
- *
- * There are other possibilities for handling the rotation of the
- * spring, and it might be interesting to explore something which has
- * better length-preserving properties. For example, with the current
- * model, an initial 180 degree rotation of the spring results in the
- * spring collapsing down to 0 size before expanding back to it's
- * natural size again.
- */
-
-static void
-spring_exert_forces (Spring *spring, double k)
-{
-  Vector da, db;
-  Vector a, b;
-  
-  a = spring->a->position;
-  b = spring->b->position;
-  
-  /* A nice vector diagram would likely help here, but my ASCII-art
-   * skills aren't up to the task. Here's how to make your own
-   * diagram:
-   *
-   * Draw a and b, and the vector AB from a to b
-   * Find the center of AB
-   * Draw spring->offset so that its center point is on the center of AB
-   * Draw da from a to the initial point of spring->offset
-   * Draw db from b to the final point of spring->offset
-   *
-   * The math below should be easy to verify from the diagram.
-   */
-  
-  da.x = 0.5 * (b.x - a.x - spring->offset.x);
-  da.y = 0.5 * (b.y - a.y - spring->offset.y);
-  
-  db.x = 0.5 * (a.x - b.x + spring->offset.x);
-  db.y = 0.5 * (a.y - b.y + spring->offset.y);
-  
-  object_apply_force (spring->a, k * da.x, k * da.y);
-  object_apply_force (spring->b, k * db.x, k * db.y);
-}
-
-static void
-model_step_object (Model *model, Object *object)
-{
-  Vector acceleration;
-  
-  object->theta += 0.05;
-  
-  /* Slow down due to friction. */
-  object->force.x -= model->friction * object->velocity.x;
-  object->force.y -= model->friction * object->velocity.y;
-  
-  acceleration.x = object->force.x / object->mass;
-  acceleration.y = object->force.y / object->mass;
-  
-  if (object->immobile)
-    {
-      object->velocity.x = 0;
-      object->velocity.y = 0;
-    }
-  else
-    {
-      object->velocity.x += acceleration.x;
-      object->velocity.y += acceleration.y;
-      
-      object->position.x += object->velocity.x;
-      object->position.y += object->velocity.y;
-    }
-  
-  object->force.x = 0.0;
-  object->force.y = 0.0;
-}
-
-static void
-model_init_grid (Model *model, MetaRectangle *rect, gboolean expand)
-{
-  int x, y, i, v_x, v_y;
-  int hpad, vpad;
-  
-  model->num_objects = MODEL_MAX_OBJECTS;
-  
-  model->num_springs = 0;
-  
-  i = 0;
-  if (expand)
-    {
-      hpad = rect->width / 3;
-      vpad = rect->height / 3;
-    }
-  else
-    {
-      hpad = rect->width / 6;
-      vpad = rect->height / 6;
-    }
-
-#define EXPAND_DELTA 4
-  
-  for (y = 0; y < GRID_HEIGHT; y++)
-    for (x = 0; x < GRID_WIDTH; x++)
-      {
-	if (expand)
-	  {
-	    if (y == 0)
-	      v_y = - EXPAND_DELTA * g_random_double();
-	    else if (y == GRID_HEIGHT - 1)
-	      v_y = EXPAND_DELTA * g_random_double();
-	    else
-	      v_y = 2 * EXPAND_DELTA * g_random_double() - EXPAND_DELTA;
-
-	    if (x == 0)
-	      v_x = - EXPAND_DELTA * g_random_double();
-	    else if (x == GRID_WIDTH - 1)
-	      v_x = EXPAND_DELTA * g_random_double();
-	    else
-	      v_x = 2 * EXPAND_DELTA * g_random_double() - EXPAND_DELTA;
-	  }
-	else
-	  {
-	    v_x = v_y = 0;
-	  }
-	
-#if 0
-	if (expand)
-	  object_init (&model->objects[i],
-		       rect->x + x * rect->width / 6 + rect->width / 4,
-		       rect->y + y * rect->height / 6 + rect->height / 4,
-		       v_x, v_y, 20);
-	else
-#endif
-	{
-#if 0
-	    g_print ("obj: %d %d\n", rect->x + x * rect->width / 3,
-		     rect->y + y * rect->height / 3);
-#endif
-	    object_init (&model->objects[i],
-		       rect->x + x * rect->width / 3,
-		       rect->y + y * rect->height / 3,
-		       v_x, v_y, 15);
-	}	
-	
-	if (x > 0)
-	  model_add_spring (model,
-			    &model->objects[i - 1],
-			    &model->objects[i],
-			    hpad, 0);
-	
-	if (y > 0)
-	  model_add_spring (model,
-			    &model->objects[i - GRID_WIDTH],
-			    &model->objects[i],
-			    0, vpad);
-	
-	i++;
-      }
-}
-
-static void
-model_init (Model *model, MetaRectangle *rect, gboolean expand)
-{
-  model->anchor_object = NULL;
-  
-  model->k        = DEFAULT_SPRING_K;
-  model->friction = DEFAULT_FRICTION;
-  
-  model_init_grid (model, rect, expand);
-  model->steps = 0;
-  model->last_time = 0;
-}
-
-Model *
-model_new (MetaRectangle *rect, gboolean expand)
-{
-  Model *model = g_new0 (Model, 1);
-  
-  model_init (model, rect, expand);
-  
-  return model;
-}
-
-static double
-object_distance (Object *object, double x, double y)
-{
-  double dx, dy;
-
-  dx = object->position.x - x;
-  dy = object->position.y - y;
-
-  return sqrt (dx*dx + dy*dy);
-}
-
-static Object *
-model_find_nearest (Model *model, double x, double y)
-{
-  Object *object = &model->objects[0];
-  double distance, min_distance = 0.0;
-  int i;
-
-  for (i = 0; i < model->num_objects; i++) {
-    distance = object_distance (&model->objects[i], x, y);
-    if (i == 0 || distance < min_distance) {
-      min_distance = distance;
-      object = &model->objects[i];
-    }
-  }
-
-  return object;
-}
-
-void
-model_begin_move (Model *model, int x, int y)
-{
-  if (model->anchor_object)
-    model->anchor_object->immobile = 0;
-
-  model->anchor_object = model_find_nearest (model, x, y);
-  
-  model->anchor_offset.x = x - model->anchor_object->position.x;
-  model->anchor_offset.y = y - model->anchor_object->position.y;
-
-  g_print ("ypos: %f %f\n", model->anchor_object->position.y,
-	   model->anchor_object->position.x);
-  
-  g_print ("anchor offset: %f %f\n",
-	   model->anchor_offset.x,
-	   model->anchor_offset.y);
-  
-  model->anchor_object->immobile = 1;
-}
-
-void
-model_set_anchor (Model *model,
-		  int	 x,
-		  int    y)
-{
-  if (model->anchor_object)
-    model->anchor_object->immobile = 0;
-
-  model->anchor_object = model_find_nearest (model, x, y);
-  model->anchor_offset.x = model->anchor_object->position.x - x;
-  model->anchor_offset.y = model->anchor_object->position.y - y;
-
-  model->anchor_object->immobile = 1;
-}
-
-void
-model_update_move (Model *model, int x, int y)
-{
-  model->anchor_object->position.x = x - model->anchor_offset.x;
-  model->anchor_object->position.y = y - model->anchor_offset.y;
-}
-
-#define EPSILON   0.02
-
-gboolean
-model_is_calm (Model *model)
-{
-    int i;
-
-    for (i = 0; i < model->num_objects; i++)
-    {
-	if (model->objects[i].velocity.x > EPSILON	||
-	    model->objects[i].velocity.y > EPSILON	||
-	    model->objects[i].velocity.x < - EPSILON	||
-	    model->objects[i].velocity.y < - EPSILON)
-	{
-	    return FALSE;
-	}
-    }
-
-    return TRUE;
-}
-
-void
-model_step (Model *model)
-{
-  int i;
-  
-  for (i = 0; i < model->num_springs; i++)
-    spring_exert_forces (&model->springs[i], model->k);
-  
-  for (i = 0; i < model->num_objects; i++)
-    model_step_object (model, &model->objects[i]);
-}
-
-void
-model_destroy (Model *model)
-{
-  g_free (model);
-}
-
-void
-model_get_position (Model *model,
-		    int	   i,
-		    int    j,
-		    double *x,
-		    double *y)
-{
-  if (x)
-    *x = model->objects[j * 4 + i].position.x;
-
-  if (y)
-    *y = model->objects[j * 4 + i].position.y;
-}
diff --git a/src/core/spring-model.h b/src/core/spring-model.h
deleted file mode 100644
index 83ee1dad..00000000
--- a/src/core/spring-model.h
+++ /dev/null
@@ -1,33 +0,0 @@
-/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
-
-#include "window.h"
-
-typedef struct XYPair Point;
-typedef struct XYPair Vector;
-typedef struct Spring Spring;
-typedef struct Object Object;
-typedef struct Model Model;
-
-Model *model_new (MetaRectangle *rectangle,
-		  gboolean       expand);
-void model_destroy (Model *model);
-void
-model_get_position (Model *model,
-		    int	   i,
-		    int    j,
-		    double *x,
-		    double *y);
-void
-model_step (Model *model);
-void
-model_destroy (Model *model);
-gboolean
-model_is_calm (Model *model);
-void
-model_set_anchor (Model *model,
-		  int	 x,
-		  int    y);
-void
-model_begin_move (Model *model, int x, int y);
-void
-model_update_move (Model *model, int x, int y);