source: mainline/uspace/lib/gfxfont/src/glyph_bmp.c@ c78a03d

/*
 * Copyright (c) 2020 Jiri Svoboda
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup libgfxfont
 * @{
 */
/**
 * @file Glyph bitmap
 */

#include <errno.h>
#include <gfx/coord.h>
#include <gfx/glyph_bmp.h>
#include <stdlib.h>
#include "../private/glyph_bmp.h"

static errno_t gfx_glyph_bmp_extend(gfx_glyph_bmp_t *, gfx_coord2_t *);

/** Open glyph bitmap for editing.
 *
 * @param glyph Glyph
 * @param rbmp Place to store glyph bitmap
 * @return EOK on success, ENOMEM if out of memory
 */
errno_t gfx_glyph_bmp_open(gfx_glyph_t *glyph, gfx_glyph_bmp_t **rbmp)
{
        gfx_glyph_bmp_t *bmp;

        bmp = calloc(1, sizeof(gfx_glyph_bmp_t));
        if (bmp == NULL)
                return ENOMEM;

        bmp->rect.p0.x = 0;
        bmp->rect.p0.y = 0;
        bmp->rect.p1.x = 0;
        bmp->rect.p1.y = 0;
        bmp->pixels = NULL;

        bmp->glyph = glyph;
        *rbmp = bmp;
        return EOK;
}

/** Save glyph bitmap.
 *
 * @param bmp Glyph bitmap
 * @return EOK on success, ENOMEM if out of memory
 */
errno_t gfx_glyph_bmp_save(gfx_glyph_bmp_t *bmp)
{
        return EOK;
}

/** Close glyph bitmap.
 *
 * @param bmp Glyph bitmap
 */
void gfx_glyph_bmp_close(gfx_glyph_bmp_t *bmp)
{
        free(bmp->pixels);
        free(bmp);
}

/** Get pixel from glyph bitmap.
 *
 * @param bmp Glyph bitmap
 * @param x X-coordinate
 * @param y Y-coordinate
 * @return Pixel value
 */
int gfx_glyph_bmp_getpix(gfx_glyph_bmp_t *bmp, gfx_coord_t x, gfx_coord_t y)
{
        gfx_coord2_t pos;
        size_t pitch;

        pos.x = x;
        pos.y = y;
        if (!gfx_pix_inside_rect(&pos, &bmp->rect))
                return 0;

        pitch = bmp->rect.p1.x - bmp->rect.p0.x;
        return bmp->pixels[(y - bmp->rect.p0.y) * pitch +
            (x - bmp->rect.p0.x)];
}

/** Set pixel in glyph bitmap.
 *
 * @param bmp Glyph bitmap
 * @param x X-coordinate
 * @param y Y-coordinate
 *
 * @reutrn EOK on success, ENOMEM if out of memory
 */
errno_t gfx_glyph_bmp_setpix(gfx_glyph_bmp_t *bmp, gfx_coord_t x,
    gfx_coord_t y, int value)
{
        gfx_coord2_t pos;
        size_t pitch;
        errno_t rc;

        pos.x = x;
        pos.y = y;
        if (!gfx_pix_inside_rect(&pos, &bmp->rect)) {
                rc = gfx_glyph_bmp_extend(bmp, &pos);
                if (rc != EOK)
                        return rc;
        }

        pitch = bmp->rect.p1.x - bmp->rect.p0.x;
        bmp->pixels[(y - bmp->rect.p0.y) * pitch +
            (x - bmp->rect.p0.x)] = value;
        return EOK;
}

/** Extend glyph bitmap to cover a patricular pixel.
 *
 * @param bmp Glyph bitmap
 * @param pos Pixel position
 *
 * @return EOK on sucesss, ENOMEM if out of memory
 */
static errno_t gfx_glyph_bmp_extend(gfx_glyph_bmp_t *bmp, gfx_coord2_t *pos)
{
        gfx_rect_t prect;
        gfx_rect_t nrect;
        int *npixels;
        size_t npitch;
        size_t opitch;
        gfx_coord_t x, y;

        /* Compute new rectangle enveloping current rectangle and new pixel */
        prect.p0 = *pos;
        prect.p1.x = prect.p0.x + 1;
        prect.p1.y = prect.p0.y + 1;

        gfx_rect_envelope(&bmp->rect, &prect, &nrect);

        /* Allocate new pixel array */
        npixels = calloc(sizeof(int), (nrect.p1.x - nrect.p0.x) *
            (nrect.p1.y - nrect.p0.y));
        if (npixels == NULL)
                return ENOMEM;

        /* Transfer pixel data */
        opitch = bmp->rect.p1.x - bmp->rect.p0.x;
        npitch = nrect.p1.x - nrect.p0.x;

        for (y = bmp->rect.p0.y; y < bmp->rect.p1.y; y++) {
                for (x = bmp->rect.p0.x; x < bmp->rect.p1.x; x++) {
                        npixels[(y - nrect.p0.y) * npitch + x - nrect.p0.x] =
                            bmp->pixels[(y - bmp->rect.p0.y) * opitch +
                                x - bmp->rect.p0.x];
                }
        }

        /* Switch new and old data */
        free(bmp->pixels);
        bmp->pixels = npixels;
        bmp->rect = nrect;

        return EOK;
}

/** @}
 */