GRASS GIS 8 Programmer's Manual  8.2.2dev(2023)-5c00b4e944
color_org.c
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1 #include <stdlib.h>
2 
3 #include <grass/gis.h>
4 #include <grass/raster.h>
5 
6 #define LOOKUP_COLORS 2048
7 
8 static void organize_lookup(struct Colors *, int);
9 static int organize_fp_lookup(struct Colors *, int);
10 static int double_comp(const void *, const void *);
11 
12 void Rast__organize_colors(struct Colors *colors)
13 {
14  /* don't do anything if called recursively */
15  if (!colors->organizing) {
16  colors->organizing = 1;
17 
18  organize_lookup(colors, 0);
19  organize_lookup(colors, 1);
20 
21  organize_fp_lookup(colors, 0);
22  organize_fp_lookup(colors, 1);
23 
24  colors->organizing = 0;
25  }
26 }
27 
28 static int organize_fp_lookup(struct Colors *colors, int mod)
29 {
30  int i;
31  DCELL val;
32  struct _Color_Info_ *cp;
33  struct _Color_Rule_ *rule;
34 
35  if (mod)
36  cp = &colors->modular;
37  else
38  cp = &colors->fixed;
39 
40  /* if one of the lookup tables exist, don't do anything */
41  if (cp->lookup.active || cp->fp_lookup.active)
42  return 1;
43  if (cp->n_rules == 0)
44  return 1;
45 
46  cp->fp_lookup.vals = (DCELL *)
47  G_calloc(cp->n_rules * 2, sizeof(DCELL));
48  /* 2 endpoints for each rule */
49  cp->fp_lookup.rules = (struct _Color_Rule_ **)
50  G_calloc(cp->n_rules * 2, sizeof(struct _Color_Rule_ *));
51 
52  /* get the list of DCELL values from set of all lows and highs
53  of all rules */
54  /* NOTE: if low==high in a rule, the value appears twice in a list
55  but if low==high of the previous, rule the value appears only once */
56 
57  i = 0;
58  /* go through the list of rules from end to beginning,
59  because rules are sored in reverse order of reading,
60  and we want to read the in correct order, to ignore
61  the same values in the end of rule and beginning of next rule */
62 
63  /* first go to the last rules */
64  for (rule = cp->rules; rule->next; rule = rule->next) ;
65  /* now traverse from the last to the first rule */
66  for (; rule; rule = rule->prev) {
67  /* check if the min is the same as previous maximum */
68  if (i == 0 || rule->low.value != cp->fp_lookup.vals[i - 1])
69  cp->fp_lookup.vals[i++] = rule->low.value;
70  cp->fp_lookup.vals[i++] = rule->high.value;
71  }
72  cp->fp_lookup.nalloc = i;
73 
74  /* now sort the values */
75  qsort((char *)cp->fp_lookup.vals, cp->fp_lookup.nalloc,
76  sizeof(DCELL), &double_comp);
77 
78  /* now find the rule to apply between each 2 values in a list */
79  for (i = 0; i < cp->fp_lookup.nalloc - 1; i++) {
80  val = (cp->fp_lookup.vals[i] + cp->fp_lookup.vals[i + 1]) / 2.;
81  /* fprintf (stderr, "%lf %lf ", cp->fp_lookup.vals[i], cp->fp_lookup.vals[i+1]); */
82 
83  for (rule = cp->rules; rule; rule = rule->next)
84  if (rule->low.value <= val && val <= rule->high.value)
85  break;
86  /* if(rule) fprintf (stderr, "%d %lf %lf %d\n", i, rule->low.value, rule->high.value, rule);
87  else fprintf (stderr, "null\n");
88  */
89  cp->fp_lookup.rules[i] = rule;
90  }
91  cp->fp_lookup.active = 1;
92 
93  return 0;
94 }
95 
96 static void organize_lookup(struct Colors *colors, int mod)
97 {
98  int i, n;
99  CELL x;
100  CELL cat[LOOKUP_COLORS];
101  struct _Color_Info_ *cp;
102 
103  /* don't do anything if the color structure is float */
104  if (colors->is_float)
105  return;
106 
107  if (mod)
108  cp = &colors->modular;
109  else
110  cp = &colors->fixed;
111 
112  if (cp->lookup.active)
113  return;
114 
115  n = (CELL) cp->max - (CELL) cp->min + 1;
116  if (n >= LOOKUP_COLORS || n <= 0)
117  return;
118 
119  x = (CELL) cp->min;
120  for (i = 0; i < n; i++)
121  cat[i] = x++;;
122 
123  cp->lookup.nalloc = n;
124  cp->lookup.red = (unsigned char *)G_malloc(n);
125  cp->lookup.grn = (unsigned char *)G_malloc(n);
126  cp->lookup.blu = (unsigned char *)G_malloc(n);
127  cp->lookup.set = (unsigned char *)G_malloc(n);
128 
129  G_zero(cp->lookup.set, n * sizeof(unsigned char));
130  Rast__lookup_colors((void *)cat,
131  cp->lookup.red, cp->lookup.grn, cp->lookup.blu,
132  cp->lookup.set, n, colors, mod, 1, CELL_TYPE);
133 
134  cp->lookup.active = 1;
135 }
136 
137 static int double_comp(const void *xx, const void *yy)
138 {
139  const DCELL *x = xx, *y = yy;
140 
141  if (*x < *y)
142  return -1;
143  else if (*x == *y)
144  return 0;
145  else
146  return 1;
147 }
void Rast__organize_colors(struct Colors *colors)
Definition: color_org.c:12
#define LOOKUP_COLORS
Definition: color_org.c:6
void G_zero(void *, int)
Zero out a buffer, buf, of length i.
Definition: gis/zero.c:23
#define G_calloc(m, n)
Definition: defs/gis.h:113
#define G_malloc(n)
Definition: defs/gis.h:112
void Rast__lookup_colors(const void *, unsigned char *, unsigned char *, unsigned char *, unsigned char *, int, struct Colors *, int, int, RASTER_MAP_TYPE)
Lookup an array of colors.
Definition: color_look.c:195
double DCELL
Definition: gis.h:614
int CELL
Definition: gis.h:613
#define CELL_TYPE
Definition: raster.h:11
Definition: gis.h:677
int is_float
Definition: gis.h:681
struct _Color_Info_ fixed
Definition: gis.h:690
struct _Color_Info_ modular
Definition: gis.h:691
int organizing
Definition: gis.h:694
struct _Color_Info_::@3 lookup
unsigned char * red
Definition: gis.h:656
DCELL * vals
Definition: gis.h:666
struct _Color_Info_::@4 fp_lookup
DCELL max
Definition: gis.h:673
int active
Definition: gis.h:661
unsigned char * set
Definition: gis.h:659
unsigned char * blu
Definition: gis.h:658
struct _Color_Rule_ * rules
Definition: gis.h:651
unsigned char * grn
Definition: gis.h:657
DCELL min
Definition: gis.h:673
int n_rules
Definition: gis.h:652
int nalloc
Definition: gis.h:660
struct _Color_Rule_ * prev
Definition: gis.h:646
struct _Color_Rule_ * next
Definition: gis.h:645
struct _Color_Value_ low high
Definition: gis.h:644
DCELL value
Definition: gis.h:636
#define x