gtk/modules/engines/pixbuf/pixbuf-render.c
Owen Taylor ac939d3355 Add gradient rendering -- if the source width/height is zero, render a
Thu Feb  7 00:21:21 2002  Owen Taylor  <otaylor@redhat.com>

        * pixbuf-render.c (pixbuf_render): Add gradient
        rendering -- if the source width/height is zero,
        render a gradient from the surrounding values.
2002-02-07 05:43:55 +00:00

804 lines
20 KiB
C

/* GTK+ Pixbuf Engine
* Copyright (C) 1998-2000 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*
* Written by Owen Taylor <otaylor@redhat.com>, based on code by
* Carsten Haitzler <raster@rasterman.com>
*/
#include <string.h>
#include "pixbuf.h"
#include <gdk-pixbuf/gdk-pixbuf.h>
GCache *pixbuf_cache = NULL;
static GdkPixbuf *
bilinear_gradient (GdkPixbuf *src,
gint src_x,
gint src_y,
gint width,
gint height)
{
guint n_channels = gdk_pixbuf_get_n_channels (src);
guint src_rowstride = gdk_pixbuf_get_rowstride (src);
guchar *src_pixels = gdk_pixbuf_get_pixels (src);
guchar *p1, *p2, *p3, *p4;
guint dest_rowstride;
guchar *dest_pixels;
GdkPixbuf *result;
int i, j, k;
p1 = src_pixels + (src_y - 1) * src_rowstride + (src_x - 1) * n_channels;
p2 = p1 + n_channels;
p3 = src_pixels + src_y * src_rowstride + (src_x - 1) * n_channels;
p4 = p3 + n_channels;
result = gdk_pixbuf_new (GDK_COLORSPACE_RGB, n_channels == 4, 8,
width, height);
dest_rowstride = gdk_pixbuf_get_rowstride (result);
dest_pixels = gdk_pixbuf_get_pixels (result);
for (i = 0; i < height; i++)
{
guchar *p = dest_pixels + dest_rowstride *i;
guint v[4];
gint dv[4];
for (k = 0; k < n_channels; k++)
{
guint start = ((height - i) * p1[k] + (1 + i) * p3[k]) / (height + 1);
guint end = ((height - i) * p2[k] + (1 + i) * p4[k]) / (height + 1);
dv[k] = (((gint)end - (gint)start) << 16) / (width + 1);
v[k] = (start << 16) + dv[k] + 0x8000;
}
for (j = width; j; j--)
{
for (k = 0; k < n_channels; k++)
{
*(p++) = v[k] >> 16;
v[k] += dv[k];
}
}
}
return result;
}
static GdkPixbuf *
horizontal_gradient (GdkPixbuf *src,
gint src_x,
gint src_y,
gint width,
gint height)
{
guint n_channels = gdk_pixbuf_get_n_channels (src);
guint src_rowstride = gdk_pixbuf_get_rowstride (src);
guchar *src_pixels = gdk_pixbuf_get_pixels (src);
guint dest_rowstride;
guchar *dest_pixels;
GdkPixbuf *result;
int i, j, k;
result = gdk_pixbuf_new (GDK_COLORSPACE_RGB, n_channels == 4, 8,
width, height);
dest_rowstride = gdk_pixbuf_get_rowstride (result);
dest_pixels = gdk_pixbuf_get_pixels (result);
for (i = 0; i < height; i++)
{
guchar *p = dest_pixels + dest_rowstride *i;
guchar *p1 = src_pixels + (src_y + i) * src_rowstride + (src_x - 1) * n_channels;
guchar *p2 = p1 + n_channels;
guint v[4];
gint dv[4];
for (k = 0; k < n_channels; k++)
{
dv[k] = (((gint)p2[k] - (gint)p1[k]) << 16) / (width + 1);
v[k] = (p1[k] << 16) + dv[k] + 0x8000;
}
for (j = width; j; j--)
{
for (k = 0; k < n_channels; k++)
{
*(p++) = v[k] >> 16;
v[k] += dv[k];
}
}
}
return result;
}
static GdkPixbuf *
vertical_gradient (GdkPixbuf *src,
gint src_x,
gint src_y,
gint width,
gint height)
{
guint n_channels = gdk_pixbuf_get_n_channels (src);
guint src_rowstride = gdk_pixbuf_get_rowstride (src);
guchar *src_pixels = gdk_pixbuf_get_pixels (src);
guchar *top_pixels, *bottom_pixels;
guint dest_rowstride;
guchar *dest_pixels;
GdkPixbuf *result;
int i, j;
top_pixels = src_pixels + (src_y - 1) * src_rowstride + (src_x) * n_channels;
bottom_pixels = top_pixels + src_rowstride;
result = gdk_pixbuf_new (GDK_COLORSPACE_RGB, n_channels == 4, 8,
width, height);
dest_rowstride = gdk_pixbuf_get_rowstride (result);
dest_pixels = gdk_pixbuf_get_pixels (result);
for (i = 0; i < height; i++)
{
guchar *p = dest_pixels + dest_rowstride *i;
guchar *p1 = top_pixels;
guchar *p2 = bottom_pixels;
for (j = width * n_channels; j; j--)
*(p++) = ((height - i) * *(p1++) + (1 + i) * *(p2++)) / (height + 1);
}
return result;
}
static GdkPixbuf *
replicate_single (GdkPixbuf *src,
gint src_x,
gint src_y,
gint width,
gint height)
{
guint n_channels = gdk_pixbuf_get_n_channels (src);
guchar *pixels = (gdk_pixbuf_get_pixels (src) +
src_y * gdk_pixbuf_get_rowstride (src) +
src_x * n_channels);
guchar r = *(pixels++);
guchar g = *(pixels++);
guchar b = *(pixels++);
guint dest_rowstride;
guchar *dest_pixels;
guchar a = 0;
GdkPixbuf *result;
int i, j;
if (n_channels == 4)
a = *(pixels++);
result = gdk_pixbuf_new (GDK_COLORSPACE_RGB, n_channels == 4, 8,
width, height);
dest_rowstride = gdk_pixbuf_get_rowstride (result);
dest_pixels = gdk_pixbuf_get_pixels (result);
for (i = 0; i < height; i++)
{
guchar *p = dest_pixels + dest_rowstride *i;
for (j = 0; j < width; j++)
{
*(p++) = r;
*(p++) = g;
*(p++) = b;
if (n_channels == 4)
*(p++) = a;
}
}
return result;
}
static GdkPixbuf *
replicate_rows (GdkPixbuf *src,
gint src_x,
gint src_y,
gint width,
gint height)
{
guint n_channels = gdk_pixbuf_get_n_channels (src);
guint src_rowstride = gdk_pixbuf_get_rowstride (src);
guchar *pixels = (gdk_pixbuf_get_pixels (src) + src_y * src_rowstride + src_x * n_channels);
guchar *dest_pixels;
GdkPixbuf *result;
guint dest_rowstride;
int i;
result = gdk_pixbuf_new (GDK_COLORSPACE_RGB, n_channels == 4, 8,
width, height);
dest_rowstride = gdk_pixbuf_get_rowstride (result);
dest_pixels = gdk_pixbuf_get_pixels (result);
for (i = 0; i < height; i++)
memcpy (dest_pixels + dest_rowstride * i, pixels, n_channels * width);
return result;
}
static GdkPixbuf *
replicate_cols (GdkPixbuf *src,
gint src_x,
gint src_y,
gint width,
gint height)
{
guint n_channels = gdk_pixbuf_get_n_channels (src);
guint src_rowstride = gdk_pixbuf_get_rowstride (src);
guchar *pixels = (gdk_pixbuf_get_pixels (src) + src_y * src_rowstride + src_x * n_channels);
guchar *dest_pixels;
GdkPixbuf *result;
guint dest_rowstride;
int i, j;
result = gdk_pixbuf_new (GDK_COLORSPACE_RGB, n_channels == 4, 8,
width, height);
dest_rowstride = gdk_pixbuf_get_rowstride (result);
dest_pixels = gdk_pixbuf_get_pixels (result);
for (i = 0; i < height; i++)
{
guchar *p = dest_pixels + dest_rowstride * i;
guchar *q = pixels + src_rowstride * i;
guchar r = *(q++);
guchar g = *(q++);
guchar b = *(q++);
guchar a = 0;
if (n_channels == 4)
a = *(q++);
for (j = 0; j < width; j++)
{
*(p++) = r;
*(p++) = g;
*(p++) = b;
if (n_channels == 4)
*(p++) = a;
}
}
return result;
}
/* Scale the rectangle (src_x, src_y, src_width, src_height)
* onto the rectangle (dest_x, dest_y, dest_width, dest_height)
* of the destination, clip by clip_rect and render
*/
static void
pixbuf_render (GdkPixbuf *src,
guint hints,
GdkWindow *window,
GdkBitmap *mask,
GdkRectangle *clip_rect,
gint src_x,
gint src_y,
gint src_width,
gint src_height,
gint dest_x,
gint dest_y,
gint dest_width,
gint dest_height)
{
GdkPixbuf *tmp_pixbuf;
GdkRectangle rect;
int x_offset, y_offset;
gboolean has_alpha = gdk_pixbuf_get_has_alpha (src);
gint src_rowstride = gdk_pixbuf_get_rowstride (src);
gint src_n_channels = gdk_pixbuf_get_n_channels (src);
if (dest_width <= 0 || dest_height <= 0)
return;
rect.x = dest_x;
rect.y = dest_y;
rect.width = dest_width;
rect.height = dest_height;
if (hints & THEME_MISSING)
return;
/* FIXME: Because we use the mask to shape windows, we don't use
* clip_rect to clip what we draw to the mask, only to clip
* what we actually draw. But this leads to the horrible ineffiency
* of scale the whole image to get a little bit of it.
*/
if (!mask && clip_rect)
{
if (!gdk_rectangle_intersect (clip_rect, &rect, &rect))
return;
}
if (dest_width == src_width && dest_height == src_height)
{
tmp_pixbuf = g_object_ref (src);
x_offset = src_x + rect.x - dest_x;
y_offset = src_y + rect.y - dest_y;
}
else if (src_width == 0 && src_height == 0)
{
tmp_pixbuf = bilinear_gradient (src, src_x, src_y, dest_width, dest_height);
x_offset = rect.x - dest_x;
y_offset = rect.y - dest_y;
}
else if (src_width == 0 && dest_height == src_height)
{
tmp_pixbuf = horizontal_gradient (src, src_x, src_y, dest_width, dest_height);
x_offset = rect.x - dest_x;
y_offset = rect.y - dest_y;
}
else if (src_height == 0 && dest_width == src_width)
{
tmp_pixbuf = vertical_gradient (src, src_x, src_y, dest_width, dest_height);
x_offset = rect.x - dest_x;
y_offset = rect.y - dest_y;
}
else if ((hints & THEME_CONSTANT_COLS) && (hints & THEME_CONSTANT_ROWS))
{
tmp_pixbuf = replicate_single (src, src_x, src_y, dest_width, dest_height);
x_offset = rect.x - dest_x;
y_offset = rect.y - dest_y;
}
else if (dest_width == src_width && (hints & THEME_CONSTANT_COLS))
{
tmp_pixbuf = replicate_rows (src, src_x, src_y, dest_width, dest_height);
x_offset = rect.x - dest_x;
y_offset = rect.y - dest_y;
}
else if (dest_height == src_height && (hints & THEME_CONSTANT_ROWS))
{
tmp_pixbuf = replicate_cols (src, src_x, src_y, dest_width, dest_height);
x_offset = rect.x - dest_x;
y_offset = rect.y - dest_y;
}
else
{
double x_scale = (double)dest_width / src_width;
double y_scale = (double)dest_height / src_height;
guchar *pixels;
GdkPixbuf *partial_src;
pixels = (gdk_pixbuf_get_pixels (src)
+ src_y * src_rowstride
+ src_x * src_n_channels);
partial_src = gdk_pixbuf_new_from_data (pixels, GDK_COLORSPACE_RGB,
has_alpha,
8, src_width, src_height,
src_rowstride,
NULL, NULL);
tmp_pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB,
has_alpha, 8,
rect.width, rect.height);
gdk_pixbuf_scale (partial_src, tmp_pixbuf,
0, 0, rect.width, rect.height,
dest_x - rect.x, dest_y - rect.y,
x_scale, y_scale,
GDK_INTERP_BILINEAR);
gdk_pixbuf_unref (partial_src);
x_offset = 0;
y_offset = 0;
}
if (mask)
{
gdk_pixbuf_render_threshold_alpha (tmp_pixbuf, mask,
x_offset, y_offset,
rect.x, rect.y,
rect.width, rect.height,
128);
}
gdk_pixbuf_render_to_drawable_alpha (tmp_pixbuf, window,
x_offset, y_offset,
rect.x, rect.y,
rect.width, rect.height,
GDK_PIXBUF_ALPHA_FULL, 128,
GDK_RGB_DITHER_NORMAL,
0, 0);
gdk_pixbuf_unref (tmp_pixbuf);
}
ThemePixbuf *
theme_pixbuf_new (void)
{
ThemePixbuf *result = g_new0 (ThemePixbuf, 1);
result->filename = NULL;
result->pixbuf = NULL;
result->stretch = TRUE;
result->border_left = 0;
result->border_right = 0;
result->border_bottom = 0;
result->border_top = 0;
return result;
}
void
theme_pixbuf_destroy (ThemePixbuf *theme_pb)
{
theme_pixbuf_set_filename (theme_pb, NULL);
g_free (theme_pb);
}
void
theme_pixbuf_set_filename (ThemePixbuf *theme_pb,
const char *filename)
{
if (theme_pb->pixbuf)
{
g_cache_remove (pixbuf_cache, theme_pb->pixbuf);
theme_pb->pixbuf = NULL;
}
if (theme_pb->filename)
g_free (theme_pb->filename);
if (filename)
theme_pb->filename = g_strdup (filename);
else
theme_pb->filename = NULL;
}
static guint
compute_hint (GdkPixbuf *pixbuf,
gint x0,
gint x1,
gint y0,
gint y1)
{
int i, j;
int hints = THEME_CONSTANT_ROWS | THEME_CONSTANT_COLS | THEME_MISSING;
int n_channels = gdk_pixbuf_get_n_channels (pixbuf);
guchar *data = gdk_pixbuf_get_pixels (pixbuf);
int rowstride = gdk_pixbuf_get_rowstride (pixbuf);
if (x0 == x1 || y0 == y1)
return 0;
for (i = y0; i < y1; i++)
{
guchar *p = data + i * rowstride + x0 * n_channels;
guchar r = p[0];
guchar g = p[1];
guchar b = p[2];
guchar a = 0;
if (n_channels == 4)
a = p[3];
for (j = x0; j < x1 ; j++)
{
if (n_channels != 4 || p[3] != 0)
{
hints &= ~THEME_MISSING;
if (!(hints & THEME_CONSTANT_ROWS))
goto cols;
}
if (r != *(p++) ||
g != *(p++) ||
b != *(p++) ||
(n_channels != 4 && a != *(p++)))
{
hints &= ~THEME_CONSTANT_ROWS;
if (!(hints & THEME_MISSING))
goto cols;
}
}
}
cols:
for (i = y0 + 1; i < y1; i++)
{
guchar *base = data + y0 * rowstride + x0 * n_channels;
guchar *p = data + i * rowstride + x0 * n_channels;
if (memcmp (p, base, n_channels * (x1 - x0)) != 0)
{
hints &= ~THEME_CONSTANT_COLS;
return hints;
}
}
return hints;
}
static void
theme_pixbuf_compute_hints (ThemePixbuf *theme_pb)
{
int i, j;
gint width = gdk_pixbuf_get_width (theme_pb->pixbuf);
gint height = gdk_pixbuf_get_height (theme_pb->pixbuf);
if (theme_pb->border_left + theme_pb->border_right > width ||
theme_pb->border_top + theme_pb->border_bottom > height)
{
g_warning ("Invalid borders specified for theme pixmap:\n"
" %s,\n"
"borders don't fit within the image", theme_pb->filename);
if (theme_pb->border_left + theme_pb->border_right > width)
{
theme_pb->border_left = width / 2;
theme_pb->border_right = (width + 1) / 2;
}
if (theme_pb->border_bottom + theme_pb->border_top > height)
{
theme_pb->border_top = height / 2;
theme_pb->border_bottom = (height + 1) / 2;
}
}
for (i = 0; i < 3; i++)
{
gint y0, y1;
switch (i)
{
case 0:
y0 = 0;
y1 = theme_pb->border_top;
break;
case 1:
y0 = theme_pb->border_top;
y1 = height - theme_pb->border_bottom;
break;
default:
y0 = height - theme_pb->border_bottom;
y1 = height;
break;
}
for (j = 0; j < 3; j++)
{
gint x0, x1;
switch (j)
{
case 0:
x0 = 0;
x1 = theme_pb->border_left;
break;
case 1:
x0 = theme_pb->border_left;
x1 = width - theme_pb->border_right;
break;
default:
x0 = width - theme_pb->border_right;
x1 = width;
break;
}
theme_pb->hints[i][j] = compute_hint (theme_pb->pixbuf, x0, x1, y0, y1);
}
}
}
void
theme_pixbuf_set_border (ThemePixbuf *theme_pb,
gint left,
gint right,
gint top,
gint bottom)
{
theme_pb->border_left = left;
theme_pb->border_right = right;
theme_pb->border_top = top;
theme_pb->border_bottom = bottom;
if (theme_pb->pixbuf)
theme_pixbuf_compute_hints (theme_pb);
}
void
theme_pixbuf_set_stretch (ThemePixbuf *theme_pb,
gboolean stretch)
{
theme_pb->stretch = stretch;
if (theme_pb->pixbuf)
theme_pixbuf_compute_hints (theme_pb);
}
GdkPixbuf *
pixbuf_cache_value_new (gchar *filename)
{
GError *err = NULL;
GdkPixbuf *result = gdk_pixbuf_new_from_file (filename, &err);
if (!result)
{
g_warning ("Pixbuf theme: Cannot load pixmap file %s: %s\n",
filename, err->message);
g_error_free (err);
}
return result;
}
GdkPixbuf *
theme_pixbuf_get_pixbuf (ThemePixbuf *theme_pb)
{
if (!theme_pb->pixbuf)
{
if (!pixbuf_cache)
pixbuf_cache = g_cache_new ((GCacheNewFunc)pixbuf_cache_value_new,
(GCacheDestroyFunc)gdk_pixbuf_unref,
(GCacheDupFunc)g_strdup,
(GCacheDestroyFunc)g_free,
g_str_hash, g_direct_hash, g_str_equal);
theme_pb->pixbuf = g_cache_insert (pixbuf_cache, theme_pb->filename);
if (theme_pb->stretch)
theme_pixbuf_compute_hints (theme_pb);
}
return theme_pb->pixbuf;
}
void
theme_pixbuf_render (ThemePixbuf *theme_pb,
GdkWindow *window,
GdkBitmap *mask,
GdkRectangle *clip_rect,
guint component_mask,
gboolean center,
gint x,
gint y,
gint width,
gint height)
{
GdkPixbuf *pixbuf = theme_pixbuf_get_pixbuf (theme_pb);
gint src_x[4], src_y[4], dest_x[4], dest_y[4];
gint pixbuf_width = gdk_pixbuf_get_width (pixbuf);
gint pixbuf_height = gdk_pixbuf_get_height (pixbuf);
if (!pixbuf)
return;
if (theme_pb->stretch)
{
src_x[0] = 0;
src_x[1] = theme_pb->border_left;
src_x[2] = pixbuf_width - theme_pb->border_right;
src_x[3] = pixbuf_width;
src_y[0] = 0;
src_y[1] = theme_pb->border_top;
src_y[2] = pixbuf_height - theme_pb->border_bottom;
src_y[3] = pixbuf_height;
dest_x[0] = x;
dest_x[1] = x + theme_pb->border_left;
dest_x[2] = x + width - theme_pb->border_right;
dest_x[3] = x + width;
dest_y[0] = y;
dest_y[1] = y + theme_pb->border_top;
dest_y[2] = y + height - theme_pb->border_bottom;
dest_y[3] = y + height;
if (component_mask & COMPONENT_ALL)
component_mask = (COMPONENT_ALL - 1) & ~component_mask;
#define RENDER_COMPONENT(X1,X2,Y1,Y2) \
pixbuf_render (pixbuf, theme_pb->hints[Y1][X1], window, mask, clip_rect, \
src_x[X1], src_y[Y1], \
src_x[X2] - src_x[X1], src_y[Y2] - src_y[Y1], \
dest_x[X1], dest_y[Y1], \
dest_x[X2] - dest_x[X1], dest_y[Y2] - dest_y[Y1]);
if (component_mask & COMPONENT_NORTH_WEST)
RENDER_COMPONENT (0, 1, 0, 1);
if (component_mask & COMPONENT_NORTH)
RENDER_COMPONENT (1, 2, 0, 1);
if (component_mask & COMPONENT_NORTH_EAST)
RENDER_COMPONENT (2, 3, 0, 1);
if (component_mask & COMPONENT_WEST)
RENDER_COMPONENT (0, 1, 1, 2);
if (component_mask & COMPONENT_CENTER)
RENDER_COMPONENT (1, 2, 1, 2);
if (component_mask & COMPONENT_EAST)
RENDER_COMPONENT (2, 3, 1, 2);
if (component_mask & COMPONENT_SOUTH_WEST)
RENDER_COMPONENT (0, 1, 2, 3);
if (component_mask & COMPONENT_SOUTH)
RENDER_COMPONENT (1, 2, 2, 3);
if (component_mask & COMPONENT_SOUTH_EAST)
RENDER_COMPONENT (2, 3, 2, 3);
}
else
{
if (center)
{
x += (width - pixbuf_width) / 2;
y += (height - pixbuf_height) / 2;
pixbuf_render (pixbuf, 0, window, NULL, clip_rect,
0, 0,
pixbuf_width, pixbuf_height,
x, y,
pixbuf_width, pixbuf_height);
}
else
{
GdkPixmap *tmp_pixmap;
GdkGC *tmp_gc;
GdkGCValues gc_values;
tmp_pixmap = gdk_pixmap_new (window,
pixbuf_width,
pixbuf_height,
-1);
tmp_gc = gdk_gc_new (tmp_pixmap);
gdk_pixbuf_render_to_drawable (pixbuf, tmp_pixmap, tmp_gc,
0, 0,
0, 0,
pixbuf_width, pixbuf_height,
GDK_RGB_DITHER_NORMAL,
0, 0);
gdk_gc_unref (tmp_gc);
gc_values.fill = GDK_TILED;
gc_values.tile = tmp_pixmap;
tmp_gc = gdk_gc_new_with_values (window,
&gc_values, GDK_GC_FILL | GDK_GC_TILE);
if (clip_rect)
gdk_draw_rectangle (window, tmp_gc, TRUE,
clip_rect->x, clip_rect->y, clip_rect->width, clip_rect->height);
else
gdk_draw_rectangle (window, tmp_gc, TRUE, x, y, width, height);
gdk_gc_unref (tmp_gc);
gdk_pixmap_unref (tmp_pixmap);
}
}
}