awesome/objects/widgets/imagebox.c

/*
 * imagebox.c - imagebox widget
 *
 * Copyright © 2008-2009 Julien Danjou <julien@danjou.info>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 */

#include "objects/widget.h"
#include "luaa.h"

/** The imagebox private data structure */
typedef struct
{
    /** Imagebox image */
    cairo_surface_t *image;
    color_t bg;
    bool resize;
} imagebox_data_t;

static area_t
imagebox_extents(lua_State *L, widget_t *widget)
{
    area_t geometry = { .x = 0, .y = 0 };
    imagebox_data_t *d = widget->data;

    if(d->image)
    {
        geometry.width = cairo_image_surface_get_width(d->image);
        geometry.height = cairo_image_surface_get_height(d->image);
    }
    else
    {
        geometry.width = 0;
        geometry.height = 0;
    }

    return geometry;
}

/** Draw an image.
 * \param widget The widget.
 * \param ctx The draw context.
 * \param geometry The geometry we draw in.
 * \param p A pointer to the object we're draw onto.
 */
static void
imagebox_draw(widget_t *widget, draw_context_t *ctx, area_t geometry, wibox_t *p)
{
    imagebox_data_t *d = widget->data;

    if(d->image && geometry.width && geometry.height)
    {
        if(d->bg.initialized)
            draw_rectangle(ctx, geometry, 1.0, true, &d->bg);

        double ratio = d->resize ? (double) geometry.height / cairo_image_surface_get_height(d->image) : 1;
        draw_surface(ctx, geometry.x, geometry.y, ratio, d->image);
    }
}

/** Delete a imagebox widget.
 * \param w The widget to destroy.
 */
static void
imagebox_destructor(widget_t *w)
{
    imagebox_data_t *d = w->data;
    if(d->image)
        cairo_surface_destroy(d->image);
    p_delete(&d);
}

static int
imagebox_set_image(lua_State *L, widget_t *widget, int idx)
{
    imagebox_data_t *d = widget->data;

    if(lua_isnil(L, idx))
    {
        if(d->image)
            cairo_surface_destroy(d->image);
        d->image = NULL;
    } else {
        bool is_surface = false;
        /* This inlines luaL_checkudata() but skips luaL_typerror() */
        if(lua_getmetatable(L, idx))
        {
            lua_getfield(L, LUA_REGISTRYINDEX, OOCAIRO_MT_NAME_SURFACE);
            if(lua_rawequal(L, -1, -2))
                is_surface = true;
            lua_pop(L, 2);
        }
        if(is_surface)
        {
            /* Ugly lua-OOCairo magic. */
            cairo_surface_t **cairo_surface = (cairo_surface_t **)luaL_checkudata(L, idx, OOCAIRO_MT_NAME_SURFACE);

            if(d->image)
                cairo_surface_destroy(d->image);

            d->image = draw_dup_image_surface(*cairo_surface);
        } else {
            luaA_checkudata(L, idx, &image_class);
            image_t *image = (void *) lua_topointer(L, idx);
            cairo_surface_t *surface = cairo_image_surface_create_for_data(
                    image_getdata(image), CAIRO_FORMAT_ARGB32,
                    image_getwidth(image), image_getheight(image),
                    image_getwidth(image) * 4);
            /* Cairo doesn't copy the data we give to it so we have to make a
             * copy of the data. This is the lazy way to do that. */
            d->image = draw_dup_image_surface(surface);
            cairo_surface_destroy(surface);
        }
    }

    widget_invalidate_bywidget(widget);
    return 0;
}

/** Imagebox widget.
 * \param L The Lua VM state.
 * \param prop The key that is being indexed.
 * \param resize Resize image.
 * \return The number of elements pushed on stack.
 * \luastack
 * \lfield image The image to display.
 * \lfield bg The background color to use.
 */
static int
luaA_imagebox_index(lua_State *L, const char *prop)
{
    widget_t *widget = luaA_checkudata(L, 1, &widget_class);
    imagebox_data_t *d = widget->data;

    if(a_strcmp(prop, "image") == 0)
        oocairo_surface_push(L, d->image);
    else if(a_strcmp(prop, "bg") == 0)
        luaA_pushcolor(L, &d->bg);
    else if(a_strcmp(prop, "resize") == 0)
        lua_pushboolean(L, d->resize);
    else
        return 0;

    return 1;
}

/** The __newindex method for a imagebox object.
 * \param L The Lua VM state.
 * \param token The key token.
 * \return The number of elements pushed on stack.
 */
static int
luaA_imagebox_newindex(lua_State *L, const char *prop)
{
    widget_t *widget = luaA_checkudata(L, 1, &widget_class);
    imagebox_data_t *d = widget->data;

    if(a_strcmp(prop, "image") == 0)
        imagebox_set_image(L, widget, 3);
    else if(a_strcmp(prop, "bg") == 0)
    {
        const char *buf;
        size_t len;
        if(lua_isnil(L, 3))
            p_clear(&d->bg, 1);
        else if((buf = luaL_checklstring(L, 3, &len)))
            color_init_unchecked(&d->bg, buf, len);
    }
    else if(a_strcmp(prop, "resize") == 0)
        d->resize = luaA_checkboolean(L, 3);
    else
        return 0;

    widget_invalidate_bywidget(widget);

    return 0;
}


/** Create a new imagebox widget.
 * \param w The widget to initialize.
 * \return A brand new widget.
 */
widget_t *
widget_imagebox(widget_t *w)
{
    imagebox_data_t *d;
    w->draw = imagebox_draw;
    w->index = luaA_imagebox_index;
    w->newindex = luaA_imagebox_newindex;
    w->destructor = imagebox_destructor;
    w->extents = imagebox_extents;
    w->data = d = p_new(imagebox_data_t, 1);
    d->resize = true;

    return w;
}

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