/*

* draw.c - draw functions

*

* Copyright © 2007-2009 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 "config.h"

#include "draw.h"

#include "globalconf.h"

#include <langinfo.h>

#include <errno.h>

#include <ctype.h>

#include <math.h>

#include <gdk-pixbuf/gdk-pixbuf.h>

#include <cairo-xcb.h>

#include <lauxlib.h>

static cairo_user_data_key_t data_key;

static inline void

free_data(void *data)

{

p_delete(&data);

}

/** Create a surface object from this image data.

* \param width The width of the image.

* \param height The height of the image

* \param data The image's data in ARGB format, will be copied by this function.

* \return Number of items pushed on the lua stack.

*/

cairo_surface_t *

draw_surface_from_data(int width, int height, uint32_t *data)

{

unsigned long int len = width * height;

unsigned long int i;

uint32_t *buffer = p_new(uint32_t, len);

cairo_surface_t *surface;

/* Cairo wants premultiplied alpha, meh :( */

for(i = 0; i < len; i++)

{

uint8_t a = (data[i] >> 24) & 0xff;

double alpha = a / 255.0;

uint8_t r = ((data[i] >> 16) & 0xff) * alpha;

uint8_t g = ((data[i] >> 8) & 0xff) * alpha;

uint8_t b = ((data[i] >> 0) & 0xff) * alpha;

buffer[i] = (a << 24) | (r << 16) | (g << 8) | b;

}

surface =

cairo_image_surface_create_for_data((unsigned char *) buffer,

CAIRO_FORMAT_ARGB32,

width,

height,

width*4);

/* This makes sure that buffer will be freed */

cairo_surface_set_user_data(surface, &data_key, buffer, &free_data);

return surface;

}

/** Create a surface object from this pixbuf

* \param buf The pixbuf

* \return Number of items pushed on the lua stack.

*/

cairo_surface_t *

draw_surface_from_pixbuf(GdkPixbuf *buf)

{

int width = gdk_pixbuf_get_width(buf);

int height = gdk_pixbuf_get_height(buf);

int pix_stride = gdk_pixbuf_get_rowstride(buf);

guchar *pixels = gdk_pixbuf_get_pixels(buf);

int channels = gdk_pixbuf_get_n_channels(buf);

cairo_surface_t *surface;

int cairo_stride;

unsigned char *cairo_pixels;

cairo_format_t format = CAIRO_FORMAT_ARGB32;

if (channels == 3)

format = CAIRO_FORMAT_RGB24;

surface = cairo_image_surface_create(format, width, height);

cairo_surface_flush(surface);

cairo_stride = cairo_image_surface_get_stride(surface);

cairo_pixels = cairo_image_surface_get_data(surface);

for (int y = 0; y < height; y++)

{

guchar *row = pixels;

uint32_t *cairo = (uint32_t *) cairo_pixels;

for (int x = 0; x < width; x++) {

if (channels == 3)

{

uint8_t r = *row++;

uint8_t g = *row++;

uint8_t b = *row++;

*cairo++ = (r << 16) | (g << 8) | b;

} else {

uint8_t r = *row++;

uint8_t g = *row++;

uint8_t b = *row++;

uint8_t a = *row++;

double alpha = a / 255.0;

r = r * alpha;

g = g * alpha;

b = b * alpha;

*cairo++ = (a << 24) | (r << 16) | (g << 8) | b;

}

}

pixels += pix_stride;

cairo_pixels += cairo_stride;

}

cairo_surface_mark_dirty(surface);

return surface;

}

static void

get_surface_size(cairo_surface_t *surface, int *width, int *height)

{

double x1, y1, x2, y2;

cairo_t *cr = cairo_create(surface);

cairo_clip_extents(cr, &x1, &y1, &x2, &y2);

cairo_destroy(cr);

*width = x2 - x1;

*height = y2 - y1;

}

/** Duplicate the specified image surface.

* \param surface The surface to copy

* \return A pointer to a new cairo image surface.

*/

cairo_surface_t *

draw_dup_image_surface(cairo_surface_t *surface)

{

cairo_surface_t *res;

int width, height;

get_surface_size(surface, &width, &height);

#if CAIRO_VERSION_MAJOR == 1 && CAIRO_VERSION_MINOR > 12

res = cairo_surface_create_similar_image(surface, CAIRO_FORMAT_ARGB32, width, height);

#else

res = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, width, height);

#endif

cairo_t *cr = cairo_create(res);

cairo_set_source_surface(cr, surface, 0, 0);

cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);

cairo_paint(cr);

cairo_destroy(cr);

return res;

}

/** Load the specified path into a cairo surface

* \param L Lua state

* \param path file to load

* \param error A place to store an error message, if needed

* \return A cairo image surface or NULL on error.

*/

cairo_surface_t *

draw_load_image(lua_State *L, const char *path, GError **error)

{

cairo_surface_t *ret;

GdkPixbuf *buf = gdk_pixbuf_new_from_file(path, error);

if (!buf)

/* error was set above */

return NULL;

ret = draw_surface_from_pixbuf(buf);

g_object_unref(buf);

return ret;

}

xcb_visualtype_t *draw_find_visual(const xcb_screen_t *s, xcb_visualid_t visual)

{

xcb_depth_iterator_t depth_iter = xcb_screen_allowed_depths_iterator(s);

if(depth_iter.data)

for(; depth_iter.rem; xcb_depth_next (&depth_iter))

for(xcb_visualtype_iterator_t visual_iter = xcb_depth_visuals_iterator(depth_iter.data);

visual_iter.rem; xcb_visualtype_next (&visual_iter))

if(visual == visual_iter.data->visual_id)

return visual_iter.data;

return NULL;

}

xcb_visualtype_t *draw_default_visual(const xcb_screen_t *s)

{

return draw_find_visual(s, s->root_visual);

}

xcb_visualtype_t *draw_argb_visual(const xcb_screen_t *s)

{

xcb_depth_iterator_t depth_iter = xcb_screen_allowed_depths_iterator(s);

if(depth_iter.data)

for(; depth_iter.rem; xcb_depth_next (&depth_iter))

if(depth_iter.data->depth == 32)

for(xcb_visualtype_iterator_t visual_iter = xcb_depth_visuals_iterator(depth_iter.data);

visual_iter.rem; xcb_visualtype_next (&visual_iter))

return visual_iter.data;

return NULL;

}

uint8_t draw_visual_depth(const xcb_screen_t *s, xcb_visualid_t vis)

{

xcb_depth_iterator_t depth_iter = xcb_screen_allowed_depths_iterator(s);

if(depth_iter.data)

for(; depth_iter.rem; xcb_depth_next (&depth_iter))

for(xcb_visualtype_iterator_t visual_iter = xcb_depth_visuals_iterator(depth_iter.data);

visual_iter.rem; xcb_visualtype_next (&visual_iter))

if(vis == visual_iter.data->visual_id)

return depth_iter.data->depth;

fatal("Could not find a visual's depth");

}

void draw_test_cairo_xcb(void)

{

xcb_pixmap_t pixmap = xcb_generate_id(globalconf.connection);

xcb_create_pixmap(globalconf.connection, globalconf.default_depth, pixmap,

globalconf.screen->root, 1, 1);

cairo_surface_t *surface = cairo_xcb_surface_create(globalconf.connection,

pixmap, globalconf.visual, 1, 1);

if(cairo_surface_status(surface) != CAIRO_STATUS_SUCCESS)

fatal("Could not set up display: got cairo surface with status %s",

cairo_status_to_string(cairo_surface_status(surface)));

cairo_surface_finish(surface);

cairo_surface_destroy(surface);

xcb_free_pixmap(globalconf.connection, pixmap);

}

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