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r_of_t.c
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C/C++ Source or Header
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1989-11-20
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13KB
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428 lines
/*
* GRAPH, Version 1.00 - 4 August 1989
*
* Copyright 1989, David Gay. All Rights Reserved.
* This software is freely redistrubatable.
*/
#include <exec/types.h>
#include <intuition/intuition.h>
#include <graphics/text.h>
#include <math.h>
#include <string.h>
#include "object.h"
#include "object/function.h"
#include "file.h"
#include "graph.h"
#include "uio.h"
#include "coords.h"
#include "list.h"
#include "grph.h"
#include "user/eval.h"
#include "user/gadgets.h"
#include "tracker.h"
#include <proto/exec.h>
#include <proto/intuition.h>
#include <proto/graphics.h>
/* (private) class r_of_t, inherits from function */
struct r_of_t {
struct function f;
char expr[EXPRLEN];
value function, derivee;
};
/* (private) class, inherits from point */
struct point_r_of_t
{
point p;
double r, theta;
};
typedef struct point_r_of_t point_r_of_t;
/*-------------------------------------------------------------------------*/
/* r_of_t class implementation */
/*-------------------------------------------------------------------------*/
/* Is the function displayable ? */
static int r_of_t_ok(const struct r_of_t *this)
{
return this->f.min != NOVAL && this->f.max != NOVAL &&
this->f.min < this->f.max &&
(this->f.steps == INOVAL || this->f.steps >= 3);
}
/* Free resources */
static void destroy_r_of_t(struct r_of_t *this)
{
free_var_list(&this->f.used);
if (this->f.calc) free_list(&this->f.pts, this->f.sizept);
this->f.calc = FALSE;
if (this->function) free_expr(this->function);
if (this->derivee) free_expr(this->derivee);
this->function = this->derivee = NULL;
}
/* Init dependant parts of function */
static int create_r_of_t(struct r_of_t *this)
{
this->f.calc = FALSE;
this->f.var.name = this->f.vname;
this->function = compile(this->expr);
if (eval_error != 0)
{
message(this->f.o.g, "Compilation error:", eval_messages[eval_error], (
char *)NULL);
return FALSE;
}
this->derivee = differentiate(this->function, this->f.vname);
if (eval_error != NOT_DIFFERENTIABLE && eval_error != 0)
{
message(this->f.o.g, "Differentiation error:", eval_messages[eval_error
], (char *)NULL);
return FALSE;
}
if (!make_var_list(this->function, &this->f.used))
init_var_list(&this->f.used);
return TRUE;
}
/* Allow user to define function */
static int edit_r_of_t(struct r_of_t *this, struct Region **ref)
{
struct Requester *req;
struct Memory *m;
struct Gadget *gl = NULL, *sd, *nd;
char from[NBLEN], to[NBLEN], steps[INTLEN], expr[EXPRLEN], tname[VARLEN], c
olour[INTLEN];
int ret = FALSE;
*ref = NULL;
/* Create requester */
double2str(from, this->f.min);
double2str(to, this->f.max);
int2str(steps, this->f.steps);
int2str(colour, this->f.colour);
strcpy(expr, this->expr);
strcpy(tname, this->f.vname);
if ((m = NewMemory()) &&
(req = InitReq(50, 20, 255, 145, m)) &&
SetReqBorder(req, 1, m) &&
AddIntuiText(&req->ReqText, "Function", 95, 6, m) &&
AddText(&gl, 0, "r(", FALSE, tname, VARLEN, TRUE, 0, RELVERIFY, 25, 20,
25, 10, TRUE, m) &&
AddText(&gl, 0, ")=", FALSE, expr, EXPRLEN, TRUE, 0, RELVERIFY, 81, 20,
160, 10, TRUE, m) &&
AddText(&gl, 0, "from ", FALSE, from, NBLEN, TRUE, 0, RELVERIFY, 49, 40
, 80, 10, TRUE, m) &&
AddText(&gl, 0, "to ", FALSE, to, NBLEN, TRUE, 0, RELVERIFY, 167, 40, 8
0, 10, TRUE, m) &&
AddText(&gl, 0, "steps ", FALSE, steps, INTLEN, TRUE, 0, RELVERIFY, 57,
60, 32, 10, TRUE, m) &&
AddText(&gl, 0, "colour ", FALSE, colour, INTLEN, TRUE, 0, RELVERIFY, 1
56, 60, 32, 10, TRUE, m) &&
(sd = AddOption(&gl, 0, "Show discontinuities", TRUE, this->f.showdisc
* SELECTED, 0, 9, 80, 10, 10, m)) &&
(nd = AddOption(&gl, 0, "Allow flat discontinuities", TRUE, this->f.nic
edisc * SELECTED, 0, 9, 100, 10, 10, m)) &&
AddBox(&gl, TRUE, "Ok", 0, RELVERIFY | ENDGADGET, 40, 120, 65, 15, FALS
E, m) &&
AddBox(&gl, FALSE, "Cancel", 0, RELVERIFY | ENDGADGET, 145, 120, 65, 15
, FALSE, m))
{
SetReqGadgets(req, gl);
if (ret = DoRequest(req, this->f.o.g, std_ghandler))
{
*ref = full_refresh(this->f.o.g);
/* Extract info */
this->f.min = str2double(from);
this->f.max = str2double(to);
this->f.steps = str2int(steps);
if ((this->f.colour = str2int(colour)) == INOVAL) this->f.colour =
1;
this->f.showdisc = (sd->Flags & SELECTED) != 0;
this->f.nicedisc = (nd->Flags & SELECTED) != 0;
strcpy(this->expr, expr);
strcpy(this->f.vname, tname);
/* Create function */
destroy_r_of_t(this);
if (this->f.o.ok = r_of_t_ok(this)) this->f.o.ok = create_r_of_t(th
is);
}
}
Free(m);
return ret;
}
/* Calculate points of function */
static int calc_r_of_t(struct r_of_t *this, int allow_mes)
{
double theta;
int i;
struct graph *const g = this->f.o.g;
int const steps = (this->f.steps == INOVAL ? DEFSTEPS : this->f.steps) - 1;
double const step = (this->f.max - this->f.min) / steps;
char func[FNAMELEN + 30];
new_list(&this->f.pts);
strcpy(func, "Can't calculate points for ");
strcat(func, this->f.o.name);
strcat(func, ":");
if (!create_quick(&this->f.var))
{
if (allow_mes) message(g, func, "Couldn't create variable", (char *)NUL
L);
else alert(g->io.win, func, "Couldn't create variable");
return FALSE;
}
/* Calculate steps points, spread evenly from min to max */
for (i = 0, theta = this->f.min; i <= steps; i++, theta += step)
{
point_r_of_t *pt = alloc_node(this->f.sizept);
if (!pt)
{ /* No mem */
free_list(&this->f.pts, this->f.sizept);
free_quick(&this->f.var);
if (allow_mes) message(g, func, "No memory", (char *)NULL);
else alert(g->io.win, func, "No memory");
return FALSE;
}
add_tail(&this->f.pts, pt);
pt->theta = theta;
set_quick(&this->f.var, theta);
pt->r = quick_eval(this->function);
pt->p.state = (eval_error == 0) ? EXISTS : 0;
/* Polar -> Rect conversion */
pt->p.x = fabs(pt->r) * cos(theta); pt->p.y = fabs(pt->r) * sin(theta);
}
free_quick(&this->f.var);
return TRUE;
}
/* Try to improve look of function by adding points. If fails, decides that
there is a discontinuity */
/* see f_of_x.c for details */
static struct Region *improve_r_of_t(struct r_of_t *this)
{
struct graph *const g = this->f.o.g;
point_r_of_t *pt, *next;
int ok = FALSE, iter, abort = FALSE;
double flatx = FLAT * (g->a.y.max - g->a.y.min) / g->io.win->Height;
double flaty = FLAT * (g->a.x.max - g->a.x.min) / g->io.win->Width;
char msg[FNAMELEN + 30];
char pass[20];
struct Requester *req;
struct Region *full = NULL;
/* Flat has no meaning when graph incorrect */
if (!this->f.o.g->ok) flatx = flaty = 0.0;
if (!this->f.calc)
{
strcpy(msg, this->f.o.name);
strcpy(msg, "not calculated!");
message(g, msg, (char *)NULL);
return NULL;
}
if (!this->derivee)
{
strcpy(msg, this->f.o.name);
strcat(msg, " wasn't differentiable");
message(g, msg, (char *)NULL);
return NULL;
}
if (!create_quick(&this->f.var))
{
message(g, "Couldn't create variable", (char *)NULL);
return NULL;
}
if (!(req = abort_request(g, "Improve: Pass 1")))
message(g, "No Memory !", (char *)NULL);
else
{
full = full_refresh(this->f.o.g);
for (iter = 1; iter <= MAXITER && !ok && !abort; iter++)
{
sprintf(pass, "Improve: Pass %d", iter);
set_abort_msg(req, pass);
ok = TRUE;
for (pt = first(&this->f.pts); succ(next = succ(pt)); pt = next)
{
if (aborted(req)) { abort = TRUE; break; }
if ((pt->p.state & (EXISTS | OK)) == EXISTS) /* Only exists */
{
double dx, dy, dr, dtheta;
pt->p.state |= OK;
pt->p.state &= ~DISC;
dtheta = next->theta - pt->theta;
set_quick(&this->f.var, pt->theta);
dr = quick_eval(this->derivee);
if (eval_error == 0)
{
double c = cos(pt->theta);
double s = sin(pt->theta);
/* A little elementary calculus ... */
dx = dr * c - pt->r * s;
dy = dr * s + pt->r * c;
if (eval_error == 0)
{
double ecartx = next->p.x - pt->p.x;
double errorx = fabs(ecartx - dtheta * dx);
double ecarty = next->p.y - pt->p.y;
double errory = fabs(ecarty - dtheta * dy);
/* Check both axes */
if ((errorx > fabs(ecartx) * MAXERROR && (!this->f.
nicedisc || errorx > flatx)) ||
(errory > fabs(ecarty) * MAXERROR && (!this->f.
nicedisc || errory > flaty)))
{
pt->p.state &= ~OK;
ok = FALSE;
if (iter == MAXITER) pt->p.state |= DISC;
else /* cut interval in 2 */
{
point_r_of_t *newpt = alloc_node(this->f.si
zept);
if (!newpt)
{
nomem(g->io.win);
abort = TRUE;
break;
}
newpt->theta = (pt->theta + next->theta) /
2;
set_quick(&this->f.var, newpt->theta);
newpt->r = quick_eval(this->function);
newpt->p.state = (eval_error == 0) ? EXISTS
: 0;
newpt->p.x = fabs(newpt->r) * cos(newpt->th
eta);
newpt->p.y = fabs(newpt->r) * sin(newpt->th
eta);
insert(&this->f.pts, newpt, pt);
}
}
}
}
}
}
}
end_abort_request(req);
}
free_quick(&this->f.var);
return full;
}
/* String representation of function */
static char *f2str_r_of_t(struct r_of_t *this, char *buf, int maxlen)
{
buf[maxlen - 1] = '\0';
strncpy(buf, "polar ", maxlen - 1);
strncat(buf, this->f.o.name, maxlen - strlen(buf) - 1);
strncat(buf, "(", maxlen - strlen(buf) - 1);
strncat(buf, this->f.vname, maxlen - strlen(buf) - 1);
strncat(buf, ")=", maxlen - strlen(buf) - 1);
strncat(buf, this->expr, maxlen - strlen(buf) - 1);
return buf;
}
static int save_r_of_t(struct r_of_t *this, FILE *f)
{
short tag = R_OF_T_TAG;
short end = R_OF_T_END;
return WRITE(f, tag) &&
WRITE(f, this->expr) &&
WRITE(f, end);
}
/* free function */
static struct Region *delete_r_of_t(struct r_of_t *this)
{
struct Region *full = full_refresh(this->f.o.g);
destroy_r_of_t(this);
FreeMem(this, sizeof(struct r_of_t));
return full;
}
/* Create a new function */
struct r_of_t *new_r_of_t(struct graph *g, char *name)
{
struct r_of_t *this = AllocMem(sizeof(struct r_of_t), MEMF_CLEAR);
if (this)
{
/* Standard init */
init_function(&this->f, g, name);
/* Local methods */
this->f.o.delete = (void *)delete_r_of_t;
this->f.o.edit = (void *)edit_r_of_t;
this->f.o.improve = (void *)improve_r_of_t;
this->f.o.f2str = (void *)f2str_r_of_t;
this->f.calcf = (void *)calc_r_of_t;
this->f.save = (void *)save_r_of_t;
this->f.sizept = sizeof(point_r_of_t);
init_var_list(&this->f.used);
return this;
}
message(g, "Couldn't create function:", "No memory", (char *)NULL);
return NULL;
}
/* Save local data to file */
/* load from file */
struct r_of_t *load_r_of_t(struct graph *g, FILE *f)
{
struct r_of_t *this = new_r_of_t(g, "");
if (this)
{
short end;
/* Read local data */
if (READ(f, this->expr) &&
READ(f, end) &&
end == R_OF_T_END)
{
load_rest(&this->f, f); /* Read standard data */
if (this->f.o.ok = r_of_t_ok(this)) this->f.o.ok = create_r_of_t(th
is);
return this;
}
delete_r_of_t(this);
}
return NULL;
}