AuroraMiddleware/gtk2
1
0
Fork 0
forked from AuroraMiddleware/gtk
Code Issues Pull Requests Projects Releases Wiki Activity

Merge branch 'better-font-rendering-demo' into 'master'

Browse Source 
gtk-demo: Improve the font rendering demo

See merge request GNOME/gtk!3923
This commit is contained in:
Matthias Clasen 2021-09-05 04:21:29 +00:00
commit 6fefae3dbb
2 changed files with 232 additions and 48 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

165
demos/gtk-demo/fontrendering.c
View File

@ -1,6 +1,11 @@
/* Pango/Font Rendering
*
* Demonstrates various aspects of font rendering.
* Demonstrates various aspects of font rendering,
* such as hinting, antialiasing and grid alignment.
*
* The demo lets you explore font rendering options
* interactively to get a feeling for they affect the
* shape and positioning of the glyphs.
*/
#include <gtk/gtk.h>
@ -17,10 +22,14 @@ static GtkWidget *down_button = NULL;
static GtkWidget *text_radio = NULL;
static GtkWidget *show_grid = NULL;
static GtkWidget *show_extents = NULL;
static GtkWidget *show_pixels = NULL;
static GtkWidget *show_outlines = NULL;
static PangoContext *context;
static int scale = 9;
static int scale = 7;
static double pixel_alpha = 1.0;
static double outline_alpha = 0.0;
static void
update_image (void)
@ -39,6 +48,7 @@ update_image (void)
cairo_hint_style_t hintstyle;
cairo_hint_metrics_t hintmetrics;
cairo_antialias_t antialias;
cairo_path_t *path;
if (!context)
context = gtk_widget_create_pango_context (image);
@ -94,10 +104,14 @@ update_image (void)
cairo_set_source_rgb (cr, 1, 1, 1);
cairo_paint (cr);
cairo_set_source_rgb (cr, 0, 0, 0);
cairo_set_source_rgba (cr, 0, 0, 0, pixel_alpha);
cairo_move_to (cr, 10, 10);
pango_cairo_show_layout (cr, layout);
pango_cairo_layout_path (cr, layout);
path = cairo_copy_path (cr);
cairo_destroy (cr);
g_object_unref (layout);
@ -136,7 +150,7 @@ update_image (void)
if (gtk_check_button_get_active (GTK_CHECK_BUTTON (show_extents)))
{
cairo_set_source_rgba (cr, 0, 0, 1, 1);
cairo_set_source_rgb (cr, 0, 0, 1);
cairo_rectangle (cr,
scale * (10 + pango_units_to_double (logical.x)) - 0.5,
@ -149,7 +163,7 @@ update_image (void)
cairo_line_to (cr, scale * (10 + pango_units_to_double (logical.x + logical.width)) + 1,
scale * (10 + pango_units_to_double (baseline)) - 0.5);
cairo_stroke (cr);
cairo_set_source_rgba (cr, 1, 0, 0, 1);
cairo_set_source_rgb (cr, 1, 0, 0);
cairo_rectangle (cr,
scale * (10 + pango_units_to_double (pink.x)) + 0.5,
scale * (10 + pango_units_to_double (pink.y)) + 0.5,
@ -158,8 +172,36 @@ update_image (void)
cairo_stroke (cr);
}
for (int i = 0; i < path->num_data; i += path->data[i].header.length)
{
cairo_path_data_t *data = &path->data[i];
switch (data->header.type)
{
case CAIRO_PATH_CURVE_TO:
data[3].point.x *= scale; data[3].point.y *= scale;
data[2].point.x *= scale; data[2].point.y *= scale;
data[1].point.x *= scale; data[1].point.y *= scale;
break;
case CAIRO_PATH_LINE_TO:
case CAIRO_PATH_MOVE_TO:
data[1].point.x *= scale; data[1].point.y *= scale;
break;
case CAIRO_PATH_CLOSE_PATH:
break;
default:
g_assert_not_reached ();
}
}
cairo_set_source_rgba (cr, 0, 0, 1, outline_alpha);
cairo_move_to (cr, scale * 20 - 0.5, scale * 20 - 0.5);
cairo_append_path (cr, path);
cairo_stroke (cr);
cairo_surface_destroy (surface);
cairo_destroy (cr);
cairo_path_destroy (path);
}
else
{
@ -167,10 +209,26 @@ update_image (void)
PangoLayoutRun *run;
PangoGlyphInfo *g;
int i, j;
GString *str;
gunichar ch;
if (*text == '\0')
text = " ";
ch = g_utf8_get_char (text);
str = g_string_new ("");
for (i = 0; i < 4; i++)
{
g_string_append_unichar (str, ch);
g_string_append_unichar (str, 0x200c);
}
layout = pango_layout_new (context);
pango_layout_set_font_description (layout, desc);
pango_layout_set_text (layout, "aaaa", -1);
pango_layout_set_text (layout, str->str, -1);
g_string_free (str, TRUE);
pango_layout_get_extents (layout, &ink, &logical);
pango_extents_to_pixels (&logical, NULL);
@ -185,7 +243,7 @@ update_image (void)
cairo_set_source_rgb (cr, 0, 0, 0);
for (i = 0; i < 4; i++)
{
g = &(run->glyphs->glyphs[i]);
g = &(run->glyphs->glyphs[2*i]);
g->geometry.width = PANGO_UNITS_ROUND (g->geometry.width * 3 / 2);
}
@ -193,7 +251,7 @@ update_image (void)
{
for (i = 0; i < 4; i++)
{
g = &(run->glyphs->glyphs[i]);
g = &(run->glyphs->glyphs[2*i]);
g->geometry.x_offset = i * (PANGO_SCALE / 4);
g->geometry.y_offset = j * (PANGO_SCALE / 4);
}
@ -212,7 +270,6 @@ update_image (void)
cairo_surface_destroy (surface);
}
gtk_picture_set_pixbuf (GTK_PICTURE (image), pixbuf2);
g_object_unref (pixbuf2);
@ -220,6 +277,78 @@ update_image (void)
pango_font_description_free (desc);
}
static gboolean fading = FALSE;
static double start_pixel_alpha;
static double end_pixel_alpha;
static double start_outline_alpha;
static double end_outline_alpha;
static gint64 start_time;
static gint64 end_time;
static double
ease_out_cubic (double t)
{
double p = t - 1;
return p * p * p + 1;
}
static gboolean
change_alpha (GtkWidget *widget,
GdkFrameClock *clock,
gpointer user_data)
{
gint64 now = g_get_monotonic_time ();
double t;
t = ease_out_cubic ((now - start_time) / (double) (end_time - start_time));
pixel_alpha = start_pixel_alpha + (end_pixel_alpha - start_pixel_alpha) * t;
outline_alpha = start_outline_alpha + (end_outline_alpha - start_outline_alpha) * t;
update_image ();
if (now >= end_time)
{
fading = FALSE;
return G_SOURCE_REMOVE;
}
return G_SOURCE_CONTINUE;
}
static void
start_alpha_fade (void)
{
gboolean pixels;
gboolean outlines;
if (fading)
return;
pixels = gtk_check_button_get_active (GTK_CHECK_BUTTON (show_pixels));
outlines = gtk_check_button_get_active (GTK_CHECK_BUTTON (show_outlines));
start_pixel_alpha = pixel_alpha;
if (pixels && outlines)
end_pixel_alpha = 0.5;
else if (pixels)
end_pixel_alpha = 1;
else
end_pixel_alpha = 0;
start_outline_alpha = outline_alpha;
if (outlines)
end_outline_alpha = 1.0;
else
end_outline_alpha = 0.0;
start_time = g_get_monotonic_time ();
end_time = start_time + G_TIME_SPAN_SECOND / 2;
fading = TRUE;
gtk_widget_add_tick_callback (window, change_alpha, NULL, NULL);
}
static void
update_buttons (void)
{
@ -227,20 +356,26 @@ update_buttons (void)
gtk_widget_set_sensitive (down_button, scale > 1);
}
static void
scale_up (void)
static gboolean
scale_up (GtkWidget *widget,
GVariant *args,
gpointer user_data)
{
scale += 1;
update_buttons ();
update_image ();
return TRUE;
}
static void
scale_down (void)
static gboolean
scale_down (GtkWidget *widget,
GVariant *args,
gpointer user_data)
{
scale -= 1;
update_buttons ();
update_image ();
return TRUE;
}
GtkWidget *
@ -266,6 +401,8 @@ do_fontrendering (GtkWidget *do_widget)
text_radio = GTK_WIDGET (gtk_builder_get_object (builder, "text_radio"));
show_grid = GTK_WIDGET (gtk_builder_get_object (builder, "show_grid"));
show_extents = GTK_WIDGET (gtk_builder_get_object (builder, "show_extents"));
show_pixels = GTK_WIDGET (gtk_builder_get_object (builder, "show_pixels"));
show_outlines = GTK_WIDGET (gtk_builder_get_object (builder, "show_outlines"));
g_signal_connect (up_button, "clicked", G_CALLBACK (scale_up), NULL);
g_signal_connect (down_button, "clicked", G_CALLBACK (scale_down), NULL);
@ -277,6 +414,8 @@ do_fontrendering (GtkWidget *do_widget)
g_signal_connect (text_radio, "notify::active", G_CALLBACK (update_image), NULL);
g_signal_connect (show_grid, "notify::active", G_CALLBACK (update_image), NULL);
g_signal_connect (show_extents, "notify::active", G_CALLBACK (update_image), NULL);
g_signal_connect (show_pixels, "notify::active", G_CALLBACK (start_alpha_fade), NULL);
g_signal_connect (show_outlines, "notify::active", G_CALLBACK (start_alpha_fade), NULL);
update_image ();

115
demos/gtk-demo/fontrendering.ui
View File

@ -1,13 +1,8 @@
<?xml version="1.0" encoding="UTF-8"?>
<interface>
<object class="GtkAdjustment" id="scale_adj">
<property name="upper">24</property>
<property name="step-increment">1</property>
<property name="page-increment">4</property>
</object>
<object class="GtkWindow" id="window">
<property name="default-width">1080</property>
<property name="default-height">430</property>
<property name="default-width">1024</property>
<property name="default-height">768</property>
<child type="titlebar">
<object class="GtkHeaderBar">
<child type="title">
@ -87,20 +82,20 @@
</object>
</child>
<child>
<object class="GtkLabel">
<property name="label">Hinting</property>
<property name="xalign">1</property>
<style>
<class name="dim-label"/>
</style>
<object class="GtkCheckButton" id="show_pixels">
<property name="label">Show _Pixels</property>
<property name="use-underline">1</property>
<property name="active">1</property>
<layout>
<property name="column">3</property>
<property name="row">0</property>
</layout>
</object>
</child>
<child>
<object class="GtkCheckButton" id="antialias">
<property name="label">Antialias</property>
<object class="GtkCheckButton" id="show_outlines">
<property name="label">Show _Outline</property>
<property name="use-underline">1</property>
<layout>
<property name="column">3</property>
<property name="row">1</property>
@ -108,45 +103,73 @@
</object>
</child>
<child>
<object class="GtkComboBoxText" id="hinting">
<property name="active">0</property>
<property name="valign">center</property>
<items>
<item translatable="yes" id="none">None</item>
<item translatable="yes" id="slight">Slight</item>
<item translatable="yes" id="medium">Medium</item>
<item translatable="yes" id="full">Full</item>
</items>
<object class="GtkBox">
<property name="spacing">6</property>
<child>
<object class="GtkLabel">
<property name="label">_Hinting</property>
<property name="use-underline">1</property>
<property name="mnemonic-widget">hinting</property>
<style>
<class name="dim-label"/>
</style>
</object>
</child>
<child>
<object class="GtkComboBoxText" id="hinting">
<property name="active">0</property>
<property name="valign">center</property>
<items>
<item translatable="yes" id="none">None</item>
<item translatable="yes" id="slight">Slight</item>
<item translatable="yes" id="medium">Medium</item>
<item translatable="yes" id="full">Full</item>
</items>
</object>
</child>
<layout>
<property name="column">4</property>
<property name="column-span">2</property>
</layout>
</object>
</child>
<child>
<object class="GtkCheckButton" id="antialias">
<property name="label">_Antialias</property>
<property name="use-underline">1</property>
<property name="active">1</property>
<layout>
<property name="column">4</property>
<property name="row">1</property>
</layout>
</object>
</child>
<child>
<object class="GtkCheckButton" id="hint_metrics">
<property name="label">Hint Metrics</property>
<property name="label">Hint _Metrics</property>
<property name="use-underline">1</property>
<layout>
<property name="column">4</property>
<property name="column">5</property>
<property name="row">1</property>
</layout>
</object>
</child>
<child>
<object class="GtkCheckButton" id="show_extents">
<property name="label">Show Extents</property>
<property name="active">1</property>
<property name="label">Show _Extents</property>
<property name="use-underline">1</property>
<layout>
<property name="column">5</property>
<property name="column">6</property>
<property name="row">0</property>
</layout>
</object>
</child>
<child>
<object class="GtkCheckButton" id="show_grid">
<property name="active">1</property>
<property name="label">Show Grid</property>
<property name="label">Show _Grid</property>
<property name="use-underline">1</property>
<layout>
<property name="column">5</property>
<property name="column">6</property>
<property name="row">1</property>
</layout>
</object>
@ -157,8 +180,19 @@
<style>
<class name="circular"/>
</style>
<child>
<object class="GtkShortcutController">
<property name="scope">managed</property>
<child>
<object class="GtkShortcut">
<property name="trigger">&lt;Control&gt;plus</property>
<property name="action">activate</property>
</object>
</child>
</object>
</child>
<layout>
<property name="column">6</property>
<property name="column">7</property>
<property name="row">0</property>
</layout>
</object>
@ -169,8 +203,19 @@
<style>
<class name="circular"/>
</style>
<child>
<object class="GtkShortcutController">
<property name="scope">managed</property>
<child>
<object class="GtkShortcut">
<property name="trigger">&lt;Control&gt;minus</property>
<property name="action">activate</property>
</object>
</child>
</object>
</child>
<layout>
<property name="column">6</property>
<property name="column">7</property>
<property name="row">1</property>
</layout>
</object>
@ -179,7 +224,7 @@
<object class="GtkLabel">
<property name="hexpand">1</property>
<layout>
<property name="column">7</property>
<property name="column">8</property>
</layout>
</object>
</child>