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/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
/* Marco gradient test program */
/*
* Copyright (C) 2002 Havoc Pennington
*
* 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 St, Fifth Floor, Boston, MA
* 02110-1301, USA. */
#include "gradient.h"
#include <gtk/gtk.h>
typedef void (* RenderGradientFunc) (GdkDrawable *drawable,
cairo_t *cr,
int width,
int height);
static void
draw_checkerboard (GdkDrawable *drawable,
int width,
int height)
{
gint i, j, xcount, ycount;
GdkColor color1, color2;
cairo_t *cr;
#define CHECK_SIZE 10
#define SPACING 2
color1.red = 30000;
color1.green = 30000;
color1.blue = 30000;
color2.red = 50000;
color2.green = 50000;
color2.blue = 50000;
cr = gdk_cairo_create (drawable);
xcount = 0;
i = SPACING;
while (i < width)
{
j = SPACING;
ycount = xcount % 2; /* start with even/odd depending on row */
while (j < height)
{
if (ycount % 2)
gdk_cairo_set_source_color (cr, &color1);
else
gdk_cairo_set_source_color (cr, &color2);
/* If we're outside event->area, this will do nothing.
* It might be mildly more efficient if we handled
* the clipping ourselves, but again we're feeling lazy.
*/
cairo_rectangle (cr, i, j, CHECK_SIZE, CHECK_SIZE);
cairo_fill (cr);
j += CHECK_SIZE + SPACING;
++ycount;
}
i += CHECK_SIZE + SPACING;
++xcount;
}
cairo_destroy (cr);
}
static void
render_simple (GdkDrawable *drawable,
cairo_t *cr,
int width, int height,
MetaGradientType type,
gboolean with_alpha)
{
GdkPixbuf *pixbuf;
GdkColor from, to;
gdk_color_parse ("blue", &from);
gdk_color_parse ("green", &to);
pixbuf = meta_gradient_create_simple (width, height,
&from, &to,
type);
if (with_alpha)
{
const unsigned char alphas[] = { 0xff, 0xaa, 0x2f, 0x0, 0xcc, 0xff, 0xff };
if (!gdk_pixbuf_get_has_alpha (pixbuf))
{
GdkPixbuf *new_pixbuf;
new_pixbuf = gdk_pixbuf_add_alpha (pixbuf, FALSE, 0, 0, 0);
g_object_unref (G_OBJECT (pixbuf));
pixbuf = new_pixbuf;
}
meta_gradient_add_alpha (pixbuf,
alphas, G_N_ELEMENTS (alphas),
META_GRADIENT_HORIZONTAL);
draw_checkerboard (drawable, width, height);
}
gdk_cairo_set_source_pixbuf (cr, pixbuf, 0, 0);
cairo_rectangle (cr, 0, 0, width, height);
cairo_fill (cr);
g_object_unref (G_OBJECT (pixbuf));
}
static void
render_vertical_func (GdkDrawable *drawable,
cairo_t *cr,
int width, int height)
{
render_simple (drawable, cr, width, height, META_GRADIENT_VERTICAL, FALSE);
}
static void
render_horizontal_func (GdkDrawable *drawable,
cairo_t *cr,
int width, int height)
{
render_simple (drawable, cr, width, height, META_GRADIENT_HORIZONTAL, FALSE);
}
static void
render_diagonal_func (GdkDrawable *drawable,
cairo_t *cr,
int width, int height)
{
render_simple (drawable, cr, width, height, META_GRADIENT_DIAGONAL, FALSE);
}
static void
render_diagonal_alpha_func (GdkDrawable *drawable,
cairo_t *cr,
int width, int height)
{
render_simple (drawable, cr, width, height, META_GRADIENT_DIAGONAL, TRUE);
}
static void
render_multi (GdkDrawable *drawable,
cairo_t *cr,
int width, int height,
MetaGradientType type)
{
GdkPixbuf *pixbuf;
#define N_COLORS 5
GdkColor colors[N_COLORS];
gdk_color_parse ("red", &colors[0]);
gdk_color_parse ("blue", &colors[1]);
gdk_color_parse ("orange", &colors[2]);
gdk_color_parse ("pink", &colors[3]);
gdk_color_parse ("green", &colors[4]);
pixbuf = meta_gradient_create_multi (width, height,
colors, N_COLORS,
type);
gdk_cairo_set_source_pixbuf (cr, pixbuf, 0, 0);
cairo_rectangle (cr, 0, 0, width, height);
cairo_fill (cr);
g_object_unref (G_OBJECT (pixbuf));
#undef N_COLORS
}
static void
render_vertical_multi_func (GdkDrawable *drawable,
cairo_t *cr,
int width, int height)
{
render_multi (drawable, cr, width, height, META_GRADIENT_VERTICAL);
}
static void
render_horizontal_multi_func (GdkDrawable *drawable,
cairo_t *cr,
int width, int height)
{
render_multi (drawable, cr, width, height, META_GRADIENT_HORIZONTAL);
}
static void
render_diagonal_multi_func (GdkDrawable *drawable,
cairo_t *cr,
int width, int height)
{
render_multi (drawable, cr, width, height, META_GRADIENT_DIAGONAL);
}
static void
render_interwoven_func (GdkDrawable *drawable,
cairo_t *cr,
int width, int height)
{
GdkPixbuf *pixbuf;
#define N_COLORS 4
GdkColor colors[N_COLORS];
gdk_color_parse ("red", &colors[0]);
gdk_color_parse ("blue", &colors[1]);
gdk_color_parse ("pink", &colors[2]);
gdk_color_parse ("green", &colors[3]);
pixbuf = meta_gradient_create_interwoven (width, height,
colors, height / 10,
colors + 2, height / 14);
gdk_cairo_set_source_pixbuf (cr, pixbuf, 0, 0);
cairo_rectangle (cr, 0, 0, width, height);
cairo_fill (cr);
g_object_unref (G_OBJECT (pixbuf));
}
static gboolean
expose_callback (GtkWidget *widget,
GdkEventExpose *event,
gpointer data)
{
RenderGradientFunc func = data;
GdkWindow *window;
GtkAllocation allocation;
GtkStyle *style;
cairo_t *cr;
style = gtk_widget_get_style (widget);
gtk_widget_get_allocation (widget, &allocation);
window = gtk_widget_get_window (widget);
cr = gdk_cairo_create (window);
gdk_cairo_set_source_color (cr, &style->fg[gtk_widget_get_state (widget)]);
(* func) (window,
cr,
allocation.width,
allocation.height);
cairo_destroy (cr);
return TRUE;
}
static GtkWidget*
create_gradient_window (const char *title,
RenderGradientFunc func)
{
GtkWidget *window;
GtkWidget *drawing_area;
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_title (GTK_WINDOW (window), title);
drawing_area = gtk_drawing_area_new ();
gtk_widget_set_size_request (drawing_area, 1, 1);
gtk_window_set_default_size (GTK_WINDOW (window), 175, 175);
g_signal_connect (G_OBJECT (drawing_area),
"expose_event",
G_CALLBACK (expose_callback),
func);
gtk_container_add (GTK_CONTAINER (window), drawing_area);
gtk_widget_show_all (window);
return window;
}
static void
meta_gradient_test (void)
{
GtkWidget *window;
window = create_gradient_window ("Simple vertical",
render_vertical_func);
window = create_gradient_window ("Simple horizontal",
render_horizontal_func);
window = create_gradient_window ("Simple diagonal",
render_diagonal_func);
window = create_gradient_window ("Multi vertical",
render_vertical_multi_func);
window = create_gradient_window ("Multi horizontal",
render_horizontal_multi_func);
window = create_gradient_window ("Multi diagonal",
render_diagonal_multi_func);
window = create_gradient_window ("Interwoven",
render_interwoven_func);
window = create_gradient_window ("Simple diagonal with horizontal multi alpha",
render_diagonal_alpha_func);
}
int
main (int argc, char **argv)
{
gtk_init (&argc, &argv);
meta_gradient_test ();
gtk_main ();
return 0;
}
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