gs_bm.c

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/*!
   \file lib/ogsf/gs_bm.c

   \brief OGSF library - manipulating bitmaps (lower level functions)

   GRASS OpenGL gsurf OGSF Library 

   (C) 1999-2008 by the GRASS Development Team

   This program is free software under the 
   GNU General Public License (>=v2). 
   Read the file COPYING that comes with GRASS
   for details.

   \author Bill Brown USACERL, GMSL/University of Illinois (September 1993)
   \author Doxygenized by Martin Landa <landa.martin gmail.com> (May 2008)
 */

#include <grass/gis.h>
#include <grass/glocale.h>
#include <grass/ogsf.h>

#include "gsget.h"

/*!
   \brief Do combining of bitmaps, make bitmaps from other data w/maskval

   \param frombuff data buffer
   \param maskval mask type
   \param rows number of rows
   \param cols number of cols

   \return pointer to BM struct
 */
struct BM *gsbm_make_mask(typbuff * frombuff, float maskval, int rows,
                          int cols)
{
    int i, j, ioff;
    struct BM *bm;
    float curval;

    bm = BM_create(cols, rows);

    if (frombuff) {
        if (frombuff->bm) {
            for (i = 0; i < rows; i++) {
                ioff = i * cols;

                for (j = 0; j < cols; j++) {
                    BM_set(bm, j, i, BM_get(frombuff->bm, j, i));
                }
            }
        }
        else {
            for (i = 0; i < rows; i++) {
                ioff = i * cols;

                for (j = 0; j < cols; j++) {
                    if (GET_MAPATT(frombuff, (ioff + j), curval)) {
                        BM_set(bm, j, i, (curval == maskval));
                    }
                    else {
                        BM_set(bm, j, i, 0);    /* doesn't mask nulls */
                    }
                }
            }
        }
    }

    return (bm);
}

/*!
   \brief Zero mask

   \param map pointer to BM struct
 */
void gsbm_zero_mask(struct BM *map)
{
    int numbytes;
    unsigned char *buf;

    numbytes = map->bytes * map->rows;
    buf = map->data;

    while (numbytes--) {
        *buf++ = 0;
    }

    return;
}

/*!
   \brief mask types
 */
#define MASK_OR         1
#define MASK_ORNOT      2
#define MASK_AND        3
#define MASK_XOR        4

/*!
   \brief Mask bitmap

   Must be same size, ORs bitmaps & stores in bmvar

   \param bmvar bitmap (BM) to changed
   \param bmcom bitmap (BM)
   \param mask_type mask type (see mask types macros)

   \return -1 on failure (bitmap mispatch)
   \return 0 on success
 */
static int gsbm_masks(struct BM *bmvar, struct BM *bmcon, const int mask_type)
{
    int i;
    int varsize, consize, numbytes;

    varsize = bmvar->rows * bmvar->cols;
    consize = bmcon->rows * bmcon->cols;
    numbytes = bmvar->bytes * bmvar->rows;

    if (bmcon && bmvar) {
        if (varsize != consize) {
            G_warning(_("Bitmap mismatch"));
            return (-1);
        }

        if (bmvar->sparse || bmcon->sparse)
            return (-1);

        switch (mask_type) {
        case MASK_OR:
            for (i = 0; i < numbytes; i++)
                bmvar->data[i] |= bmcon->data[i];
            break;
        case MASK_ORNOT:
            for (i = 0; i < numbytes; i++)
                bmvar->data[i] |= ~bmcon->data[i];
            break;
        case MASK_AND:
            for (i = 0; i < numbytes; i++)
                bmvar->data[i] &= bmcon->data[i];
            break;
        case MASK_XOR:
            for (i = 0; i < numbytes; i++)
                bmvar->data[i] ^= bmcon->data[i];
            break;
        }

        return (0);
    }

    return (-1);
}

/*!
   \brief Mask bitmap (mask type OR)

   Must be same size, ORs bitmaps & stores in bmvar

   \param bmvar bitmap (BM) to changed
   \param bmcom bitmap (BM)
   \param mask_type mask type (see mask types macros)

   \return -1 on failure (bitmap mispatch)
   \return 0 on success
 */
int gsbm_or_masks(struct BM *bmvar, struct BM *bmcon)
{
    return gsbm_masks(bmvar, bmcon, MASK_OR);
}

/*!
   \brief Mask bitmap (mask type ORNOT)

   Must be same size, ORNOTs bitmaps & stores in bmvar

   \param bmvar bitmap (BM) to changed
   \param bmcom bitmap (BM)
   \param mask_type mask type (see mask types macros)

   \return -1 on failure (bitmap mispatch)
   \return 0 on success
 */
int gsbm_ornot_masks(struct BM *bmvar, struct BM *bmcon)
{
    return gsbm_masks(bmvar, bmcon, MASK_ORNOT);
}

/*!
   \brief Mask bitmap (mask type ADD)

   Must be same size, ADDs bitmaps & stores in bmvar

   \param bmvar bitmap (BM) to changed
   \param bmcom bitmap (BM)
   \param mask_type mask type (see mask types macros)

   \return -1 on failure (bitmap mispatch)
   \return 0 on success
 */
int gsbm_and_masks(struct BM *bmvar, struct BM *bmcon)
{
    return gsbm_masks(bmvar, bmcon, MASK_AND);
}

/*!
   \brief Mask bitmap (mask type XOR)

   Must be same size, XORs bitmaps & stores in bmvar

   \param bmvar bitmap (BM) to changed
   \param bmcom bitmap (BM)
   \param mask_type mask type (see mask types macros)

   \return -1 on failure (bitmap mispatch)
   \return 0 on success
 */
int gsbm_xor_masks(struct BM *bmvar, struct BM *bmcon)
{
    return gsbm_masks(bmvar, bmcon, MASK_XOR);
}

/*!
   \brief Update current maps

   \param surf surface (geosurf)

   \return 0
   \return 1
 */
int gs_update_curmask(geosurf * surf)
{
    struct BM *b_mask, *b_topo, *b_color;
    typbuff *t_topo, *t_mask, *t_color;
    int row, col, offset, destroy_ok = 1;
    gsurf_att *coloratt;

    G_debug(5, "gs_update_curmask(): id=%d", surf->gsurf_id);

    if (surf->mask_needupdate) {
        surf->mask_needupdate = 0;
        surf->norm_needupdate = 1;      /* edges will need to be recalculated */

        t_topo = gs_get_att_typbuff(surf, ATT_TOPO, 0);

        if (!t_topo) {
            surf->mask_needupdate = 1;

            return (0);
        }

        if (surf->nz_topo || surf->nz_color ||
            gs_mask_defined(surf) || t_topo->nm) {
            b_mask = b_topo = b_color = NULL;

            if (!surf->curmask) {
                surf->curmask = BM_create(surf->cols, surf->rows);
            }
            else {
                gsbm_zero_mask(surf->curmask);
            }

            if (surf->nz_topo) {
                /* no_zero elevation */
                b_topo = gsbm_make_mask(t_topo, 0.0, surf->rows, surf->cols);
            }

            /* make_mask_from_color */
            if (surf->nz_color && surf->att[ATT_COLOR].att_src == MAP_ATT) {
                t_color = gs_get_att_typbuff(surf, ATT_COLOR, 0);
                coloratt = &(surf->att[ATT_COLOR]);
                b_color = BM_create(surf->cols, surf->rows);

                for (row = 0; row < surf->rows; row++) {
                    for (col = 0; col < surf->cols; col++) {
                        offset = row * surf->cols + col;
                        BM_set(b_color, col, row,
                               (NULL_COLOR ==
                                gs_mapcolor(t_color, coloratt, offset)));
                    }
                }
            }

            if (gs_mask_defined(surf)) {
                t_mask = gs_get_att_typbuff(surf, ATT_MASK, 0);

                if (t_mask->bm) {
                    b_mask = t_mask->bm;
                    destroy_ok = 0;
                }
                else {
                    b_mask = BM_create(surf->cols, surf->rows);
                    gs_set_maskmode((int)surf->att[ATT_MASK].constant);

                    for (row = 0; row < surf->rows; row++) {
                        for (col = 0; col < surf->cols; col++) {
                            offset = row * surf->cols + col;
                            BM_set(b_mask, col, row,
                                   gs_masked(t_mask, col, row, offset));
                        }
                    }
                }
            }

            if (b_topo) {
                G_debug(5, "gs_update_curmask(): update topo mask");
                gsbm_or_masks(surf->curmask, b_topo);
                BM_destroy(b_topo);
            }

            if (b_color) {
                G_debug(5, "gs_update_curmask(): update color mask");
                gsbm_or_masks(surf->curmask, b_color);
                BM_destroy(b_color);
            }

            if (t_topo->nm) {
                G_debug(5, "gs_update_curmask(): update elev null mask");
                gsbm_or_masks(surf->curmask, t_topo->nm);
            }

            if (b_mask) {
                G_debug(5, "gs_update_curmask(): update mask mask");

                if (t_mask->bm) {
                    if (surf->att[ATT_MASK].constant) {
                        /* invert */
                        gsbm_or_masks(surf->curmask, t_mask->bm);
                    }
                    else {
                        gsbm_ornot_masks(surf->curmask, t_mask->bm);
                    }
                }
                else {
                    gsbm_or_masks(surf->curmask, b_mask);
                }

                if (destroy_ok) {
                    BM_destroy(b_mask);
                }
            }

            /* TODO: update surf->zminmasked */
            return (1);
        }
        else if (surf->curmask) {
            BM_destroy(surf->curmask);
            surf->curmask = NULL;
            surf->zminmasked = surf->zmin;
        }

    }

    return (0);
}

/*!
   \brief Print bitmap to stderr

   \param bm bitmap (BM)
 */
void print_bm(struct BM *bm)
{
    int i, j;

    for (i = 0; i < bm->rows; i++) {
        for (j = 0; j < bm->cols; j++) {
            fprintf(stderr, "%d ", BM_get(bm, j, i));
        }

        fprintf(stderr, "\n");
    }

    return;
}