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IABSD.fr/xenocara/lib/pixman/demos/scale.c
matthieu
- lib/pixman/demos/scale.c
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/* * Copyright 2012, Red Hat, Inc. * Copyright 2012, Soren Sandmann * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. * * Author: Soren Sandmann <soren.sandmann@gmail.com> */ #ifdef HAVE_CONFIG_H #include "pixman-config.h" #endif #include <math.h> #include <gtk/gtk.h> #include <pixman.h> #include <stdlib.h> #include "gtk-utils.h" typedef struct { GtkBuilder * builder; pixman_image_t * original; GtkAdjustment * scale_x_adjustment; GtkAdjustment * scale_y_adjustment; GtkAdjustment * rotate_adjustment; GtkAdjustment * subsample_adjustment; int scaled_width; int scaled_height; } app_t; static GtkWidget * get_widget (app_t *app, const char *name) { GtkWidget *widget = GTK_WIDGET (gtk_builder_get_object (app->builder, name)); if (!widget) g_error ("Widget %s not found\n", name); return widget; } /* Figure out the boundary of a diameter=1 circle transformed into an ellipse * by trans. Proof that this is the correct calculation: * * Transform x,y to u,v by this matrix calculation: * * |u| |a c| |x| * |v| = |b d|*|y| * * Horizontal component: * * u = ax+cy (1) * * For each x,y on a radius-1 circle (p is angle to the point): * * x^2+y^2 = 1 * x = cos(p) * y = sin(p) * dx/dp = -sin(p) = -y * dy/dp = cos(p) = x * * Figure out derivative of (1) relative to p: * * du/dp = a(dx/dp) + c(dy/dp) * = -ay + cx * * The min and max u are when du/dp is zero: * * -ay + cx = 0 * cx = ay * c = ay/x (2) * y = cx/a (3) * * Substitute (2) into (1) and simplify: * * u = ax + ay^2/x * = a(x^2+y^2)/x * = a/x (because x^2+y^2 = 1) * x = a/u (4) * * Substitute (4) into (3) and simplify: * * y = c(a/u)/a * y = c/u (5) * * Square (4) and (5) and add: * * x^2+y^2 = (a^2+c^2)/u^2 * * But x^2+y^2 is 1: * * 1 = (a^2+c^2)/u^2 * u^2 = a^2+c^2 * u = hypot(a,c) * * Similarily the max/min of v is at: * * v = hypot(b,d) * */ static void compute_extents (pixman_f_transform_t *trans, double *sx, double *sy) { *sx = hypot (trans->m[0][0], trans->m[0][1]) / trans->m[2][2]; *sy = hypot (trans->m[1][0], trans->m[1][1]) / trans->m[2][2]; } typedef struct { char name [20]; int value; } named_int_t; static const named_int_t filters[] = { { "Box", PIXMAN_KERNEL_BOX }, { "Impulse", PIXMAN_KERNEL_IMPULSE }, { "Linear", PIXMAN_KERNEL_LINEAR }, { "Cubic", PIXMAN_KERNEL_CUBIC }, { "Lanczos2", PIXMAN_KERNEL_LANCZOS2 }, { "Lanczos3", PIXMAN_KERNEL_LANCZOS3 }, { "Lanczos3 Stretched", PIXMAN_KERNEL_LANCZOS3_STRETCHED }, { "Gaussian", PIXMAN_KERNEL_GAUSSIAN }, }; static const named_int_t repeats[] = { { "None", PIXMAN_REPEAT_NONE }, { "Normal", PIXMAN_REPEAT_NORMAL }, { "Reflect", PIXMAN_REPEAT_REFLECT }, { "Pad", PIXMAN_REPEAT_PAD }, }; static int get_value (app_t *app, const named_int_t table[], const char *box_name) { GtkComboBox *box = GTK_COMBO_BOX (get_widget (app, box_name)); return table[gtk_combo_box_get_active (box)].value; } static void copy_to_counterpart (app_t *app, GObject *object) { static const char *xy_map[] = { "reconstruct_x_combo_box", "reconstruct_y_combo_box", "sample_x_combo_box", "sample_y_combo_box", "scale_x_adjustment", "scale_y_adjustment", }; GObject *counterpart = NULL; int i; for (i = 0; i < G_N_ELEMENTS (xy_map); i += 2) { GObject *x = gtk_builder_get_object (app->builder, xy_map[i]); GObject *y = gtk_builder_get_object (app->builder, xy_map[i + 1]); if (object == x) counterpart = y; if (object == y) counterpart = x; } if (!counterpart) return; if (GTK_IS_COMBO_BOX (counterpart)) { gtk_combo_box_set_active ( GTK_COMBO_BOX (counterpart), gtk_combo_box_get_active ( GTK_COMBO_BOX (object))); } else if (GTK_IS_ADJUSTMENT (counterpart)) { gtk_adjustment_set_value ( GTK_ADJUSTMENT (counterpart), gtk_adjustment_get_value ( GTK_ADJUSTMENT (object))); } } static double to_scale (double v) { return pow (1.15, v); } static void rescale (GtkWidget *may_be_null, app_t *app) { pixman_f_transform_t ftransform; pixman_transform_t transform; double new_width, new_height; double fscale_x, fscale_y; double rotation; pixman_fixed_t *params; int n_params; double sx, sy; pixman_f_transform_init_identity (&ftransform); if (may_be_null && gtk_toggle_button_get_active ( GTK_TOGGLE_BUTTON (get_widget (app, "lock_checkbutton")))) { copy_to_counterpart (app, G_OBJECT (may_be_null)); } fscale_x = gtk_adjustment_get_value (app->scale_x_adjustment); fscale_y = gtk_adjustment_get_value (app->scale_y_adjustment); rotation = gtk_adjustment_get_value (app->rotate_adjustment); fscale_x = to_scale (fscale_x); fscale_y = to_scale (fscale_y); new_width = pixman_image_get_width (app->original) * fscale_x; new_height = pixman_image_get_height (app->original) * fscale_y; pixman_f_transform_scale (&ftransform, NULL, fscale_x, fscale_y); pixman_f_transform_translate (&ftransform, NULL, - new_width / 2.0, - new_height / 2.0); rotation = (rotation / 360.0) * 2 * M_PI; pixman_f_transform_rotate (&ftransform, NULL, cos (rotation), sin (rotation)); pixman_f_transform_translate (&ftransform, NULL, new_width / 2.0, new_height / 2.0); pixman_f_transform_invert (&ftransform, &ftransform); compute_extents (&ftransform, &sx, &sy); pixman_transform_from_pixman_f_transform (&transform, &ftransform); pixman_image_set_transform (app->original, &transform); params = pixman_filter_create_separable_convolution ( &n_params, sx * 65536.0 + 0.5, sy * 65536.0 + 0.5, get_value (app, filters, "reconstruct_x_combo_box"), get_value (app, filters, "reconstruct_y_combo_box"), get_value (app, filters, "sample_x_combo_box"), get_value (app, filters, "sample_y_combo_box"), gtk_adjustment_get_value (app->subsample_adjustment), gtk_adjustment_get_value (app->subsample_adjustment)); pixman_image_set_filter (app->original, PIXMAN_FILTER_SEPARABLE_CONVOLUTION, params, n_params); pixman_image_set_repeat ( app->original, get_value (app, repeats, "repeat_combo_box")); free (params); app->scaled_width = ceil (new_width); app->scaled_height = ceil (new_height); gtk_widget_set_size_request ( get_widget (app, "drawing_area"), new_width + 0.5, new_height + 0.5); gtk_widget_queue_draw ( get_widget (app, "drawing_area")); } static gboolean on_draw (GtkWidget *widget, cairo_t *cr, gpointer user_data) { app_t *app = user_data; GdkRectangle area; cairo_surface_t *surface; pixman_image_t *tmp; uint32_t *pixels; gdk_cairo_get_clip_rectangle(cr, &area); pixels = calloc (1, area.width * area.height * 4); tmp = pixman_image_create_bits ( PIXMAN_a8r8g8b8, area.width, area.height, pixels, area.width * 4); if (area.x < app->scaled_width && area.y < app->scaled_height) { pixman_image_composite ( PIXMAN_OP_SRC, app->original, NULL, tmp, area.x, area.y, 0, 0, 0, 0, app->scaled_width - area.x, app->scaled_height - area.y); } surface = cairo_image_surface_create_for_data ( (uint8_t *)pixels, CAIRO_FORMAT_ARGB32, area.width, area.height, area.width * 4); cairo_set_source_surface (cr, surface, area.x, area.y); cairo_paint (cr); cairo_surface_destroy (surface); free (pixels); pixman_image_unref (tmp); return TRUE; } static void set_up_combo_box (app_t *app, const char *box_name, int n_entries, const named_int_t table[]) { GtkWidget *widget = get_widget (app, box_name); GtkListStore *model; GtkCellRenderer *cell; int i; model = gtk_list_store_new (1, G_TYPE_STRING); cell = gtk_cell_renderer_text_new (); gtk_cell_layout_pack_start (GTK_CELL_LAYOUT (widget), cell, TRUE); gtk_cell_layout_set_attributes (GTK_CELL_LAYOUT (widget), cell, "text", 0, NULL); gtk_combo_box_set_model (GTK_COMBO_BOX (widget), GTK_TREE_MODEL (model)); for (i = 0; i < n_entries; ++i) { const named_int_t *info = &(table[i]); GtkTreeIter iter; gtk_list_store_append (model, &iter); gtk_list_store_set (model, &iter, 0, info->name, -1); } gtk_combo_box_set_active (GTK_COMBO_BOX (widget), 0); g_signal_connect (widget, "changed", G_CALLBACK (rescale), app); } static void set_up_filter_box (app_t *app, const char *box_name) { set_up_combo_box (app, box_name, G_N_ELEMENTS (filters), filters); } static char * format_value (GtkWidget *widget, double value) { return g_strdup_printf ("%.4f", to_scale (value)); } static app_t * app_new (pixman_image_t *original) { GtkWidget *widget; app_t *app = g_malloc (sizeof *app); GError *err = NULL; app->builder = gtk_builder_new (); app->original = original; if (!gtk_builder_add_from_file (app->builder, "scale.ui", &err)) g_error ("Could not read file scale.ui: %s", err->message); app->scale_x_adjustment = GTK_ADJUSTMENT (gtk_builder_get_object (app->builder, "scale_x_adjustment")); app->scale_y_adjustment = GTK_ADJUSTMENT (gtk_builder_get_object (app->builder, "scale_y_adjustment")); app->rotate_adjustment = GTK_ADJUSTMENT (gtk_builder_get_object (app->builder, "rotate_adjustment")); app->subsample_adjustment = GTK_ADJUSTMENT (gtk_builder_get_object (app->builder, "subsample_adjustment")); g_signal_connect (app->scale_x_adjustment, "value_changed", G_CALLBACK (rescale), app); g_signal_connect (app->scale_y_adjustment, "value_changed", G_CALLBACK (rescale), app); g_signal_connect (app->rotate_adjustment, "value_changed", G_CALLBACK (rescale), app); g_signal_connect (app->subsample_adjustment, "value_changed", G_CALLBACK (rescale), app); widget = get_widget (app, "scale_x_scale"); gtk_scale_add_mark (GTK_SCALE (widget), 0.0, GTK_POS_LEFT, NULL); g_signal_connect (widget, "format_value", G_CALLBACK (format_value), app); widget = get_widget (app, "scale_y_scale"); gtk_scale_add_mark (GTK_SCALE (widget), 0.0, GTK_POS_LEFT, NULL); g_signal_connect (widget, "format_value", G_CALLBACK (format_value), app); widget = get_widget (app, "rotate_scale"); gtk_scale_add_mark (GTK_SCALE (widget), 0.0, GTK_POS_LEFT, NULL); widget = get_widget (app, "drawing_area"); g_signal_connect (widget, "draw", G_CALLBACK (on_draw), app); set_up_filter_box (app, "reconstruct_x_combo_box"); set_up_filter_box (app, "reconstruct_y_combo_box"); set_up_filter_box (app, "sample_x_combo_box"); set_up_filter_box (app, "sample_y_combo_box"); set_up_combo_box ( app, "repeat_combo_box", G_N_ELEMENTS (repeats), repeats); g_signal_connect ( gtk_builder_get_object (app->builder, "lock_checkbutton"), "toggled", G_CALLBACK (rescale), app); rescale (NULL, app); return app; } int main (int argc, char **argv) { GtkWidget *window; pixman_image_t *image; app_t *app; gtk_init (&argc, &argv); if (argc < 2) { printf ("%s <image file>\n", argv[0]); return -1; } if (!(image = pixman_image_from_file (argv[1], PIXMAN_a8r8g8b8))) { printf ("Could not load image \"%s\"\n", argv[1]); return -1; } app = app_new (image); window = get_widget (app, "main"); g_signal_connect (window, "delete_event", G_CALLBACK (gtk_main_quit), NULL); gtk_window_set_default_size (GTK_WINDOW (window), 1024, 768); gtk_widget_show_all (window); gtk_main (); return 0; }