/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */ /* * Copyright 2010 Red Hat, Inc. * * 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, see . */ /** * SECTION:meta-shadow-factory * @title: MetaShadowFactory * @short_description: Create and cache shadow textures for abritrary window shapes */ #include #include #include #include #include "cogl-utils.h" #include "region-utils.h" /* This file implements blurring the shape of a window to produce a * shadow texture. The details are discussed below; a quick summary * of the optimizations we use: * * - If the window shape is along the lines of a rounded rectangle - * a rectangular center portion with stuff at the corners - then * the blur of this - the shadow - can also be represented as a * 9-sliced texture and the same texture can be used for different * size. * * - We use the fact that a Gaussian blur is separable to do a * 2D blur as 1D blur of the rows followed by a 1D blur of the * columns. * * - For better cache efficiency, we blur rows, transpose the image * in blocks, blur rows again, and then transpose back. * * - We approximate the 1D gaussian blur as 3 successive box filters. */ typedef struct _MetaShadowCacheKey MetaShadowCacheKey; typedef struct _MetaShadowClassInfo MetaShadowClassInfo; struct _MetaShadowCacheKey { MetaWindowShape *shape; int radius; int top_fade; }; struct _MetaShadow { int ref_count; MetaShadowFactory *factory; MetaShadowCacheKey key; CoglTexture *texture; CoglPipeline *pipeline; /* The outer order is the distance the shadow extends outside the window * shape; the inner border is the unscaled portion inside the window * shape */ int outer_border_top; int inner_border_top; int outer_border_right; int inner_border_right; int outer_border_bottom; int inner_border_bottom; int outer_border_left; int inner_border_left; guint scale_width : 1; guint scale_height : 1; }; struct _MetaShadowClassInfo { const char *name; /* const so we can reuse for static definitions */ MetaShadowParams focused; MetaShadowParams unfocused; }; struct _MetaShadowFactory { GObject parent_instance; /* MetaShadowCacheKey => MetaShadow; the shadows are not referenced * by the factory, they are simply removed from the table when freed */ GHashTable *shadows; /* class name => MetaShadowClassInfo */ GHashTable *shadow_classes; }; struct _MetaShadowFactoryClass { GObjectClass parent_class; }; enum { CHANGED, LAST_SIGNAL }; static guint signals[LAST_SIGNAL] = { 0 }; /* The first element in this array also defines the default parameters * for newly created classes */ MetaShadowClassInfo default_shadow_classes[] = { { "normal", { 3, -1, 0, 3, 128 }, { 3, -1, 0, 3, 32 } }, { "dialog", { 3, -1, 0, 3, 128 }, { 3, -1, 0, 3, 32 } }, { "modal_dialog", { 3, -1, 0, 1, 128 }, { 3, -1, 0, 3, 32 } }, { "utility", { 3, -1, 0, 1, 128 }, { 3, -1, 0, 1, 32 } }, { "border", { 3, -1, 0, 3, 128 }, { 3, -1, 0, 3, 32 } }, { "menu", { 3, -1, 0, 3, 128 }, { 3, -1, 0, 0, 32 } }, { "popup-menu", { 1, 0, 0, 1, 128 }, { 1, -1, 0, 1, 128 } }, { "dropdown-menu", { 1, 10, 0, 1, 128 }, { 1, 10, 0, 1, 128 } }, { "attached", { 1, 0, 0, 1, 128 }, { 1, -1, 0, 1, 128 } } }; G_DEFINE_TYPE (MetaShadowFactory, meta_shadow_factory, G_TYPE_OBJECT); static guint meta_shadow_cache_key_hash (gconstpointer val) { const MetaShadowCacheKey *key = val; return 59 * key->radius + 67 * key->top_fade + 73 * meta_window_shape_hash (key->shape); } static gboolean meta_shadow_cache_key_equal (gconstpointer a, gconstpointer b) { const MetaShadowCacheKey *key_a = a; const MetaShadowCacheKey *key_b = b; return (key_a->radius == key_b->radius && key_a->top_fade == key_b->top_fade && meta_window_shape_equal (key_a->shape, key_b->shape)); } MetaShadow * meta_shadow_ref (MetaShadow *shadow) { shadow->ref_count++; return shadow; } void meta_shadow_unref (MetaShadow *shadow) { shadow->ref_count--; if (shadow->ref_count == 0) { if (shadow->factory) { g_hash_table_remove (shadow->factory->shadows, &shadow->key); } meta_window_shape_unref (shadow->key.shape); cogl_object_unref (shadow->texture); cogl_object_unref (shadow->pipeline); g_slice_free (MetaShadow, shadow); } } /** * meta_shadow_paint: * @window_x: x position of the region to paint a shadow for * @window_y: y position of the region to paint a shadow for * @window_width: actual width of the region to paint a shadow for * @window_height: actual height of the region to paint a shadow for * @clip: (nullable): if non-%NULL specifies the visible portion * of the shadow. * @clip_strictly: if %TRUE, drawing will be clipped strictly * to @clip, otherwise, it will be only used to optimize * drawing. * * Paints the shadow at the given position, for the specified actual * size of the region. (Since a #MetaShadow can be shared between * different sizes with the same extracted #MetaWindowShape the * size needs to be passed in here.) */ void meta_shadow_paint (MetaShadow *shadow, int window_x, int window_y, int window_width, int window_height, guint8 opacity, cairo_region_t *clip, gboolean clip_strictly) { float texture_width = cogl_texture_get_width (shadow->texture); float texture_height = cogl_texture_get_height (shadow->texture); int i, j; float src_x[4]; float src_y[4]; int dest_x[4]; int dest_y[4]; int n_x, n_y; cogl_pipeline_set_color4ub (shadow->pipeline, opacity, opacity, opacity, opacity); cogl_set_source (shadow->pipeline); if (shadow->scale_width) { n_x = 3; src_x[0] = 0.0; src_x[1] = (shadow->inner_border_left + shadow->outer_border_left) / texture_width; src_x[2] = (texture_width - (shadow->inner_border_right + shadow->outer_border_right)) / texture_width; src_x[3] = 1.0; dest_x[0] = window_x - shadow->outer_border_left; dest_x[1] = window_x + shadow->inner_border_left; dest_x[2] = window_x + window_width - shadow->inner_border_right; dest_x[3] = window_x + window_width + shadow->outer_border_right; } else { n_x = 1; src_x[0] = 0.0; src_x[1] = 1.0; dest_x[0] = window_x - shadow->outer_border_left; dest_x[1] = window_x + window_width + shadow->outer_border_right; } if (shadow->scale_height) { n_y = 3; src_y[0] = 0.0; src_y[1] = (shadow->inner_border_top + shadow->outer_border_top) / texture_height; src_y[2] = (texture_height - (shadow->inner_border_bottom + shadow->outer_border_bottom)) / texture_height; src_y[3] = 1.0; dest_y[0] = window_y - shadow->outer_border_top; dest_y[1] = window_y + shadow->inner_border_top; dest_y[2] = window_y + window_height - shadow->inner_border_bottom; dest_y[3] = window_y + window_height + shadow->outer_border_bottom; } else { n_y = 1; src_y[0] = 0.0; src_y[1] = 1.0; dest_y[0] = window_y - shadow->outer_border_top; dest_y[1] = window_y + window_height + shadow->outer_border_bottom; } for (j = 0; j < n_y; j++) { cairo_rectangle_int_t dest_rect; dest_rect.y = dest_y[j]; dest_rect.height = dest_y[j + 1] - dest_y[j]; if (dest_rect.height == 0) continue; for (i = 0; i < n_x; i++) { cairo_region_overlap_t overlap; dest_rect.x = dest_x[i]; dest_rect.width = dest_x[i + 1] - dest_x[i]; if (dest_rect.width == 0) continue; if (clip) overlap = cairo_region_contains_rectangle (clip, &dest_rect); else overlap = CAIRO_REGION_OVERLAP_IN; /* There's quite a bit of overhead from allocating a new * region in order to find an exact intersection and * generating more geometry - we make the assumption that * unless we have to clip strictly it will be cheaper to * just draw the entire rectangle. */ if (overlap == CAIRO_REGION_OVERLAP_IN || (overlap == CAIRO_REGION_OVERLAP_PART && !clip_strictly)) { cogl_rectangle_with_texture_coords (dest_x[i], dest_y[j], dest_x[i + 1], dest_y[j + 1], src_x[i], src_y[j], src_x[i + 1], src_y[j + 1]); } else if (overlap == CAIRO_REGION_OVERLAP_PART) { cairo_region_t *intersection; int n_rectangles, k; intersection = cairo_region_create_rectangle (&dest_rect); cairo_region_intersect (intersection, clip); n_rectangles = cairo_region_num_rectangles (intersection); for (k = 0; k < n_rectangles; k++) { cairo_rectangle_int_t rect; float src_x1, src_x2, src_y1, src_y2; cairo_region_get_rectangle (intersection, k, &rect); /* Separately linear interpolate X and Y coordinates in the source * based on the destination X and Y coordinates */ src_x1 = (src_x[i] * (dest_rect.x + dest_rect.width - rect.x) + src_x[i + 1] * (rect.x - dest_rect.x)) / dest_rect.width; src_x2 = (src_x[i] * (dest_rect.x + dest_rect.width - (rect.x + rect.width)) + src_x[i + 1] * (rect.x + rect.width - dest_rect.x)) / dest_rect.width; src_y1 = (src_y[j] * (dest_rect.y + dest_rect.height - rect.y) + src_y[j + 1] * (rect.y - dest_rect.y)) / dest_rect.height; src_y2 = (src_y[j] * (dest_rect.y + dest_rect.height - (rect.y + rect.height)) + src_y[j + 1] * (rect.y + rect.height - dest_rect.y)) / dest_rect.height; cogl_rectangle_with_texture_coords (rect.x, rect.y, rect.x + rect.width, rect.y + rect.height, src_x1, src_y1, src_x2, src_y2); } cairo_region_destroy (intersection); } } } } /** * meta_shadow_get_bounds: * @shadow: a #MetaShadow * @window_x: x position of the region to paint a shadow for * @window_y: y position of the region to paint a shadow for * @window_width: actual width of the region to paint a shadow for * @window_height: actual height of the region to paint a shadow for * * Computes the bounds of the pixels that will be affected by * meta_shadow_paint() */ void meta_shadow_get_bounds (MetaShadow *shadow, int window_x, int window_y, int window_width, int window_height, cairo_rectangle_int_t *bounds) { bounds->x = window_x - shadow->outer_border_left; bounds->y = window_y - shadow->outer_border_top; bounds->width = window_width + shadow->outer_border_left + shadow->outer_border_right; bounds->height = window_height + shadow->outer_border_top + shadow->outer_border_bottom; } static void meta_shadow_class_info_free (MetaShadowClassInfo *class_info) { g_free ((char *)class_info->name); g_slice_free (MetaShadowClassInfo, class_info); } static void meta_shadow_factory_init (MetaShadowFactory *factory) { guint i; factory->shadows = g_hash_table_new (meta_shadow_cache_key_hash, meta_shadow_cache_key_equal); factory->shadow_classes = g_hash_table_new_full (g_str_hash, g_str_equal, NULL, (GDestroyNotify)meta_shadow_class_info_free); for (i = 0; i < G_N_ELEMENTS (default_shadow_classes); i++) { MetaShadowClassInfo *class_info = g_slice_new (MetaShadowClassInfo); *class_info = default_shadow_classes[i]; class_info->name = g_strdup (class_info->name); g_hash_table_insert (factory->shadow_classes, (char *)class_info->name, class_info); } } static void meta_shadow_factory_finalize (GObject *object) { MetaShadowFactory *factory = META_SHADOW_FACTORY (object); GHashTableIter iter; gpointer key, value; /* Detach from the shadows in the table so we won't try to * remove them when they're freed. */ g_hash_table_iter_init (&iter, factory->shadows); while (g_hash_table_iter_next (&iter, &key, &value)) { MetaShadow *shadow = key; shadow->factory = NULL; } g_hash_table_destroy (factory->shadows); g_hash_table_destroy (factory->shadow_classes); G_OBJECT_CLASS (meta_shadow_factory_parent_class)->finalize (object); } static void meta_shadow_factory_class_init (MetaShadowFactoryClass *klass) { GObjectClass *object_class = G_OBJECT_CLASS (klass); object_class->finalize = meta_shadow_factory_finalize; signals[CHANGED] = g_signal_new ("changed", G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST, 0, NULL, NULL, NULL, G_TYPE_NONE, 0); } MetaShadowFactory * meta_shadow_factory_new (void) { return g_object_new (META_TYPE_SHADOW_FACTORY, NULL); } /** * meta_shadow_factory_get_default: * * Return value: (transfer none): the global singleton shadow factory */ MetaShadowFactory * meta_shadow_factory_get_default (void) { static MetaShadowFactory *factory; if (factory == NULL) factory = meta_shadow_factory_new (); return factory; } /* We emulate a 1D Gaussian blur by using 3 consecutive box blurs; * this produces a result that's within 3% of the original and can be * implemented much faster for large filter sizes because of the * efficiency of implementation of a box blur. Idea and formula * for choosing the box blur size come from: * * http://www.w3.org/TR/SVG/filters.html#feGaussianBlurElement * * The 2D blur is then done by blurring the rows, flipping the * image and blurring the columns. (This is possible because the * Gaussian kernel is separable - it's the product of a horizontal * blur and a vertical blur.) */ static int get_box_filter_size (int radius) { return (int)(0.5 + radius * (0.75 * sqrt(2*M_PI))); } /* The "spread" of the filter is the number of pixels from an original * pixel that it's blurred image extends. (A no-op blur that doesn't * blur would have a spread of 0.) See comment in blur_rows() for why the * odd and even cases are different */ static int get_shadow_spread (int radius) { int d; if (radius == 0) return 0; d = get_box_filter_size (radius); if (d % 2 == 1) return 3 * (d / 2); else return 3 * (d / 2) - 1; } /* This applies a single box blur pass to a horizontal range of pixels; * since the box blur has the same weight for all pixels, we can * implement an efficient sliding window algorithm where we add * in pixels coming into the window from the right and remove * them when they leave the windw to the left. * * d is the filter width; for even d shift indicates how the blurred * result is aligned with the original - does ' x ' go to ' yy' (shift=1) * or 'yy ' (shift=-1) */ static void blur_xspan (guchar *row, guchar *tmp_buffer, int row_width, int x0, int x1, int d, int shift) { int offset; int sum = 0; int i; if (d % 2 == 1) offset = d / 2; else offset = (d - shift) / 2; /* All the conditionals in here look slow, but the branches will * be well predicted and there are enough different possibilities * that trying to write this as a series of unconditional loops * is hard and not an obvious win. The main slow down here seems * to be the integer division per pixel; one possible optimization * would be to accumulate into two 16-bit integer buffers and * only divide down after all three passes. (SSE parallel implementation * of the divide step is possible.) */ for (i = x0 - d + offset; i < x1 + offset; i++) { if (i >= 0 && i < row_width) sum += row[i]; if (i >= x0 + offset) { if (i >= d) sum -= row[i - d]; tmp_buffer[i - offset] = (sum + d / 2) / d; } } memcpy (row + x0, tmp_buffer + x0, x1 - x0); } static void blur_rows (cairo_region_t *convolve_region, int x_offset, int y_offset, guchar *buffer, int buffer_width, int buffer_height, int d) { int i, j; int n_rectangles; guchar *tmp_buffer; tmp_buffer = g_malloc (buffer_width); n_rectangles = cairo_region_num_rectangles (convolve_region); for (i = 0; i < n_rectangles; i++) { cairo_rectangle_int_t rect; cairo_region_get_rectangle (convolve_region, i, &rect); for (j = y_offset + rect.y; j < y_offset + rect.y + rect.height; j++) { guchar *row = buffer + j * buffer_width; int x0 = x_offset + rect.x; int x1 = x0 + rect.width; /* We want to produce a symmetric blur that spreads a pixel * equally far to the left and right. If d is odd that happens * naturally, but for d even, we approximate by using a blur * on either side and then a centered blur of size d + 1. * (technique also from the SVG specification) */ if (d % 2 == 1) { blur_xspan (row, tmp_buffer, buffer_width, x0, x1, d, 0); blur_xspan (row, tmp_buffer, buffer_width, x0, x1, d, 0); blur_xspan (row, tmp_buffer, buffer_width, x0, x1, d, 0); } else { blur_xspan (row, tmp_buffer, buffer_width, x0, x1, d, 1); blur_xspan (row, tmp_buffer, buffer_width, x0, x1, d, -1); blur_xspan (row, tmp_buffer, buffer_width, x0, x1, d + 1, 0); } } } g_free (tmp_buffer); } static void fade_bytes (guchar *bytes, int width, int distance, int total) { guint32 multiplier = (distance * 0x10000 + 0x8000) / total; int i; for (i = 0; i < width; i++) bytes[i] = (bytes[i] * multiplier) >> 16; } /* Swaps width and height. Either swaps in-place and returns the original * buffer or allocates a new buffer, frees the original buffer and returns * the new buffer. */ static guchar * flip_buffer (guchar *buffer, int width, int height) { /* Working in blocks increases cache efficiency, compared to reading * or writing an entire column at once */ #define BLOCK_SIZE 16 if (width == height) { int i0, j0; for (j0 = 0; j0 < height; j0 += BLOCK_SIZE) for (i0 = 0; i0 <= j0; i0 += BLOCK_SIZE) { int max_j = MIN(j0 + BLOCK_SIZE, height); int max_i = MIN(i0 + BLOCK_SIZE, width); int i, j; if (i0 == j0) { for (j = j0; j < max_j; j++) for (i = i0; i < j; i++) { guchar tmp = buffer[j * width + i]; buffer[j * width + i] = buffer[i * width + j]; buffer[i * width + j] = tmp; } } else { for (j = j0; j < max_j; j++) for (i = i0; i < max_i; i++) { guchar tmp = buffer[j * width + i]; buffer[j * width + i] = buffer[i * width + j]; buffer[i * width + j] = tmp; } } } return buffer; } else { guchar *new_buffer = g_malloc (height * width); int i0, j0; for (i0 = 0; i0 < width; i0 += BLOCK_SIZE) for (j0 = 0; j0 < height; j0 += BLOCK_SIZE) { int max_j = MIN(j0 + BLOCK_SIZE, height); int max_i = MIN(i0 + BLOCK_SIZE, width); int i, j; for (i = i0; i < max_i; i++) for (j = j0; j < max_j; j++) new_buffer[i * height + j] = buffer[j * width + i]; } g_free (buffer); return new_buffer; } #undef BLOCK_SIZE } static void make_shadow (MetaShadow *shadow, cairo_region_t *region) { ClutterBackend *backend = clutter_get_default_backend (); CoglContext *ctx = clutter_backend_get_cogl_context (backend); int d = get_box_filter_size (shadow->key.radius); int spread = get_shadow_spread (shadow->key.radius); cairo_rectangle_int_t extents; cairo_region_t *row_convolve_region; cairo_region_t *column_convolve_region; guchar *buffer; int buffer_width; int buffer_height; int x_offset; int y_offset; int n_rectangles, j, k; cairo_region_get_extents (region, &extents); /* In the case where top_fade >= 0 and the portion above the top * edge of the shape will be cropped, it seems like we could create * a smaller buffer and omit the top portion, but actually, in our * multi-pass blur algorithm, the blur into the area above the window * in the first pass will contribute back to the final pixel values * for the top pixels, so we create a buffer as if we weren't cropping * and only crop when creating the CoglTexture. */ buffer_width = extents.width + 2 * spread; buffer_height = extents.height + 2 * spread; /* Round up so we have aligned rows/columns */ buffer_width = (buffer_width + 3) & ~3; buffer_height = (buffer_height + 3) & ~3; /* Square buffer allows in-place swaps, which are roughly 70% faster, but we * don't want to over-allocate too much memory. */ if (buffer_height < buffer_width && buffer_height > (3 * buffer_width) / 4) buffer_height = buffer_width; if (buffer_width < buffer_height && buffer_width > (3 * buffer_height) / 4) buffer_width = buffer_height; buffer = g_malloc0 (buffer_width * buffer_height); /* Blurring with multiple box-blur passes is fast, but (especially for * large shadow sizes) we can improve efficiency by restricting the blur * to the region that actually needs to be blurred. */ row_convolve_region = meta_make_border_region (region, spread, spread, FALSE); column_convolve_region = meta_make_border_region (region, 0, spread, TRUE); /* Offsets between coordinates of the regions and coordinates in the buffer */ x_offset = spread; y_offset = spread; /* Step 1: unblurred image */ n_rectangles = cairo_region_num_rectangles (region); for (k = 0; k < n_rectangles; k++) { cairo_rectangle_int_t rect; cairo_region_get_rectangle (region, k, &rect); for (j = y_offset + rect.y; j < y_offset + rect.y + rect.height; j++) memset (buffer + buffer_width * j + x_offset + rect.x, 255, rect.width); } /* Step 2: swap rows and columns */ buffer = flip_buffer (buffer, buffer_width, buffer_height); /* Step 3: blur rows (really columns) */ blur_rows (column_convolve_region, y_offset, x_offset, buffer, buffer_height, buffer_width, d); /* Step 4: swap rows and columns */ buffer = flip_buffer (buffer, buffer_height, buffer_width); /* Step 5: blur rows */ blur_rows (row_convolve_region, x_offset, y_offset, buffer, buffer_width, buffer_height, d); /* Step 6: fade out the top, if applicable */ if (shadow->key.top_fade >= 0) { for (j = y_offset; j < y_offset + MIN (shadow->key.top_fade, extents.height + shadow->outer_border_bottom); j++) fade_bytes(buffer + j * buffer_width, buffer_width, j - y_offset, shadow->key.top_fade); } /* We offset the passed in pixels to crop off the extra area we allocated at the top * in the case of top_fade >= 0. We also account for padding at the left for symmetry * though that doesn't currently occur. */ shadow->texture = COGL_TEXTURE (cogl_texture_2d_new_from_data (ctx, shadow->outer_border_left + extents.width + shadow->outer_border_right, shadow->outer_border_top + extents.height + shadow->outer_border_bottom, COGL_PIXEL_FORMAT_A_8, buffer_width, (buffer + (y_offset - shadow->outer_border_top) * buffer_width + (x_offset - shadow->outer_border_left)), NULL)); cairo_region_destroy (row_convolve_region); cairo_region_destroy (column_convolve_region); g_free (buffer); shadow->pipeline = meta_create_texture_pipeline (shadow->texture); } static MetaShadowParams * get_shadow_params (MetaShadowFactory *factory, const char *class_name, gboolean focused, gboolean create) { MetaShadowClassInfo *class_info = g_hash_table_lookup (factory->shadow_classes, class_name); if (class_info == NULL) { if (create) { class_info = g_slice_new0 (MetaShadowClassInfo); *class_info = default_shadow_classes[0]; class_info->name = g_strdup (class_info->name); g_hash_table_insert (factory->shadow_classes, (char *)class_info->name, class_info); } else { class_info = &default_shadow_classes[0]; } } if (focused) return &class_info->focused; else return &class_info->unfocused; } /** * meta_shadow_factory_get_shadow: * @factory: a #MetaShadowFactory * @shape: the size-invariant shape of the window's region * @width: the actual width of the window's region * @height: the actual height of the window's region * @class_name: name of the class of window shadows * @focused: whether the shadow is for a focused window * * Gets the appropriate shadow object for drawing shadows for the * specified window shape. The region that we are shadowing is specified * as a combination of a size-invariant extracted shape and the size. * In some cases, the same shadow object can be shared between sizes; * in other cases a different shadow object is used for each size. * * Return value: (transfer full): a newly referenced #MetaShadow; unref with * meta_shadow_unref() */ MetaShadow * meta_shadow_factory_get_shadow (MetaShadowFactory *factory, MetaWindowShape *shape, int width, int height, const char *class_name, gboolean focused) { MetaShadowParams *params; MetaShadowCacheKey key; MetaShadow *shadow; cairo_region_t *region; int spread; int shape_border_top, shape_border_right, shape_border_bottom, shape_border_left; int inner_border_top, inner_border_right, inner_border_bottom, inner_border_left; int outer_border_top, outer_border_right, outer_border_bottom, outer_border_left; gboolean scale_width, scale_height; gboolean cacheable; int center_width, center_height; g_return_val_if_fail (META_IS_SHADOW_FACTORY (factory), NULL); g_return_val_if_fail (shape != NULL, NULL); /* Using a single shadow texture for different window sizes only works * when there is a central scaled area that is greater than twice * the spread of the gaussian blur we are applying to get to the * shadow image. * ********* *********** * /----------\ *###########* *#############* * | | => **#*********#** => **#***********#** * | | **#** **#** **#** **#** * | | **#*********#** **#***********#** * \----------/ *###########* *#############* * ********** ************ * Original Blur Stretched Blur * * For smaller sizes, we create a separate shadow image for each size; * since we assume that there will be little reuse, we don't try to * cache such images but just recreate them. (Since the current cache * policy is to only keep around referenced shadows, there wouldn't * be any harm in caching them, it would just make the book-keeping * a bit tricker.) * * In the case where we are fading a the top, that also has to fit * within the top unscaled border. */ params = get_shadow_params (factory, class_name, focused, FALSE); spread = get_shadow_spread (params->radius); meta_window_shape_get_borders (shape, &shape_border_top, &shape_border_right, &shape_border_bottom, &shape_border_left); inner_border_top = MAX (shape_border_top + spread, params->top_fade); outer_border_top = params->top_fade >= 0 ? 0 : spread; inner_border_right = shape_border_right + spread; outer_border_right = spread; inner_border_bottom = shape_border_bottom + spread; outer_border_bottom = spread; inner_border_left = shape_border_left + spread; outer_border_left = spread; scale_width = inner_border_left + inner_border_right <= width; scale_height = inner_border_top + inner_border_bottom <= height; cacheable = scale_width && scale_height; if (cacheable) { key.shape = shape; key.radius = params->radius; key.top_fade = params->top_fade; shadow = g_hash_table_lookup (factory->shadows, &key); if (shadow) return meta_shadow_ref (shadow); } shadow = g_slice_new0 (MetaShadow); shadow->ref_count = 1; shadow->factory = factory; shadow->key.shape = meta_window_shape_ref (shape); shadow->key.radius = params->radius; shadow->key.top_fade = params->top_fade; shadow->outer_border_top = outer_border_top; shadow->inner_border_top = inner_border_top; shadow->outer_border_right = outer_border_right; shadow->inner_border_right = inner_border_right; shadow->outer_border_bottom = outer_border_bottom; shadow->inner_border_bottom = inner_border_bottom; shadow->outer_border_left = outer_border_left; shadow->inner_border_left = inner_border_left; shadow->scale_width = scale_width; if (scale_width) center_width = inner_border_left + inner_border_right - (shape_border_left + shape_border_right); else center_width = width - (shape_border_left + shape_border_right); shadow->scale_height = scale_height; if (scale_height) center_height = inner_border_top + inner_border_bottom - (shape_border_top + shape_border_bottom); else center_height = height - (shape_border_top + shape_border_bottom); g_assert (center_width >= 0 && center_height >= 0); region = meta_window_shape_to_region (shape, center_width, center_height); make_shadow (shadow, region); cairo_region_destroy (region); if (cacheable) g_hash_table_insert (factory->shadows, &shadow->key, shadow); return shadow; } /** * meta_shadow_factory_set_params: * @factory: a #MetaShadowFactory * @class_name: name of the class of shadow to set the params for. * the default shadow classes are the names of the different * theme frame types (normal, dialog, modal_dialog, utility, * border, menu, attached) and in addition, popup-menu * and dropdown-menu. * @focused: whether the shadow is for a focused window * @params: new parameter values * * Updates the shadow parameters for a particular class of shadows * for either the focused or unfocused state. If the class name * does not name an existing class, a new class will be created * (the other focus state for that class will have default values * assigned to it.) */ void meta_shadow_factory_set_params (MetaShadowFactory *factory, const char *class_name, gboolean focused, MetaShadowParams *params) { MetaShadowParams *stored_params; g_return_if_fail (META_IS_SHADOW_FACTORY (factory)); g_return_if_fail (class_name != NULL); g_return_if_fail (params != NULL); g_return_if_fail (params->radius >= 0); stored_params = get_shadow_params (factory, class_name, focused, TRUE); *stored_params = *params; g_signal_emit (factory, signals[CHANGED], 0); } /** * meta_shadow_factory_get_params: * @factory: a #MetaShadowFactory * @class_name: name of the class of shadow to get the params for * @focused: whether the shadow is for a focused window * @params: (out caller-allocates): location to store the current parameter values * * Gets the shadow parameters for a particular class of shadows * for either the focused or unfocused state. If the class name * does not name an existing class, default values will be returned * without printing an error. */ void meta_shadow_factory_get_params (MetaShadowFactory *factory, const char *class_name, gboolean focused, MetaShadowParams *params) { MetaShadowParams *stored_params; g_return_if_fail (META_IS_SHADOW_FACTORY (factory)); g_return_if_fail (class_name != NULL); stored_params = get_shadow_params (factory, class_name, focused, FALSE); if (params) *params = *stored_params; } G_DEFINE_BOXED_TYPE (MetaShadow, meta_shadow, meta_shadow_ref, meta_shadow_unref)