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Diffstat (limited to 'app/display/gimpdisplayshell-scroll.c')
| -rw-r--r-- | app/display/gimpdisplayshell-scroll.c | 529 |
1 files changed, 529 insertions, 0 deletions
diff --git a/app/display/gimpdisplayshell-scroll.c b/app/display/gimpdisplayshell-scroll.c new file mode 100644 index 0000000..ec5084d --- /dev/null +++ b/app/display/gimpdisplayshell-scroll.c @@ -0,0 +1,529 @@ +/* GIMP - The GNU Image Manipulation Program + * Copyright (C) 1995 Spencer Kimball and Peter Mattis + * + * 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 3 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 <https://www.gnu.org/licenses/>. + */ + +#include "config.h" + +#include <stdlib.h> +#include <math.h> + +#include <gegl.h> +#include <gtk/gtk.h> + +#include "libgimpmath/gimpmath.h" + +#include "display-types.h" + +#include "config/gimpdisplayconfig.h" + +#include "core/gimpimage.h" + +#include "gimpcanvas.h" +#include "gimpdisplay.h" +#include "gimpdisplay-foreach.h" +#include "gimpdisplayshell.h" +#include "gimpdisplayshell-expose.h" +#include "gimpdisplayshell-rotate.h" +#include "gimpdisplayshell-rulers.h" +#include "gimpdisplayshell-scale.h" +#include "gimpdisplayshell-scroll.h" +#include "gimpdisplayshell-scrollbars.h" +#include "gimpdisplayshell-transform.h" + + +#define OVERPAN_FACTOR 0.5 + + +/** + * gimp_display_shell_scroll: + * @shell: + * @x_offset: + * @y_offset: + * + * This function scrolls the image in the shell's viewport. It does + * actual scrolling of the pixels, so only the newly scrolled-in parts + * are freshly redrawn. + * + * Use it for incremental actual panning. + **/ +void +gimp_display_shell_scroll (GimpDisplayShell *shell, + gint x_offset, + gint y_offset) +{ + gint old_x; + gint old_y; + + g_return_if_fail (GIMP_IS_DISPLAY_SHELL (shell)); + + if (x_offset == 0 && y_offset == 0) + return; + + old_x = shell->offset_x; + old_y = shell->offset_y; + + /* freeze the active tool */ + gimp_display_shell_pause (shell); + + shell->offset_x += x_offset; + shell->offset_y += y_offset; + + gimp_display_shell_scroll_clamp_and_update (shell); + + /* the actual changes in offset */ + x_offset = (shell->offset_x - old_x); + y_offset = (shell->offset_y - old_y); + + if (x_offset || y_offset) + { + gimp_display_shell_scrolled (shell); + + gimp_overlay_box_scroll (GIMP_OVERLAY_BOX (shell->canvas), + -x_offset, -y_offset); + + } + + /* re-enable the active tool */ + gimp_display_shell_resume (shell); +} + +/** + * gimp_display_shell_scroll_set_offsets: + * @shell: + * @offset_x: + * @offset_y: + * + * This function scrolls the image in the shell's viewport. It redraws + * the entire canvas. + * + * Use it for setting the scroll offset on freshly scaled images or + * when the window is resized. For panning, use + * gimp_display_shell_scroll(). + **/ +void +gimp_display_shell_scroll_set_offset (GimpDisplayShell *shell, + gint offset_x, + gint offset_y) +{ + g_return_if_fail (GIMP_IS_DISPLAY_SHELL (shell)); + + if (shell->offset_x == offset_x && + shell->offset_y == offset_y) + return; + + gimp_display_shell_scale_save_revert_values (shell); + + /* freeze the active tool */ + gimp_display_shell_pause (shell); + + shell->offset_x = offset_x; + shell->offset_y = offset_y; + + gimp_display_shell_scroll_clamp_and_update (shell); + + gimp_display_shell_scrolled (shell); + + gimp_display_shell_expose_full (shell); + + /* re-enable the active tool */ + gimp_display_shell_resume (shell); +} + +/** + * gimp_display_shell_scroll_clamp_and_update: + * @shell: + * + * Helper function for calling two functions that are commonly called + * in pairs. + **/ +void +gimp_display_shell_scroll_clamp_and_update (GimpDisplayShell *shell) +{ + GimpImage *image; + + g_return_if_fail (GIMP_IS_DISPLAY_SHELL (shell)); + + image = gimp_display_get_image (shell->display); + + if (image) + { + if (! shell->show_all) + { + gint bounds_x; + gint bounds_y; + gint bounds_width; + gint bounds_height; + gint min_offset_x; + gint max_offset_x; + gint min_offset_y; + gint max_offset_y; + gint offset_x; + gint offset_y; + + gimp_display_shell_rotate_update_transform (shell); + + gimp_display_shell_scale_get_image_bounds (shell, + &bounds_x, + &bounds_y, + &bounds_width, + &bounds_height); + + if (shell->disp_width < bounds_width) + { + min_offset_x = bounds_x - + shell->disp_width * OVERPAN_FACTOR; + max_offset_x = bounds_x + bounds_width - + shell->disp_width * (1.0 - OVERPAN_FACTOR); + } + else + { + gint overpan_amount; + + overpan_amount = shell->disp_width - + bounds_width * (1.0 - OVERPAN_FACTOR); + + min_offset_x = bounds_x - + overpan_amount; + max_offset_x = bounds_x + bounds_width - shell->disp_width + + overpan_amount; + } + + if (shell->disp_height < bounds_height) + { + min_offset_y = bounds_y - + shell->disp_height * OVERPAN_FACTOR; + max_offset_y = bounds_y + bounds_height - + shell->disp_height * (1.0 - OVERPAN_FACTOR); + } + else + { + gint overpan_amount; + + overpan_amount = shell->disp_height - + bounds_height * (1.0 - OVERPAN_FACTOR); + + min_offset_y = bounds_y - + overpan_amount; + max_offset_y = bounds_y + bounds_height + + overpan_amount - shell->disp_height; + } + + /* Clamp */ + + offset_x = CLAMP (shell->offset_x, min_offset_x, max_offset_x); + offset_y = CLAMP (shell->offset_y, min_offset_y, max_offset_y); + + if (offset_x != shell->offset_x || offset_y != shell->offset_y) + { + shell->offset_x = offset_x; + shell->offset_y = offset_y; + + gimp_display_shell_rotate_update_transform (shell); + } + + /* Set scrollbar stepper sensitiity */ + + gimp_display_shell_scrollbars_update_steppers (shell, + min_offset_x, + max_offset_x, + min_offset_y, + max_offset_y); + } + else + { + /* Set scrollbar stepper sensitiity */ + + gimp_display_shell_scrollbars_update_steppers (shell, + G_MININT, + G_MAXINT, + G_MININT, + G_MAXINT); + } + } + else + { + shell->offset_x = 0; + shell->offset_y = 0; + } + + gimp_display_shell_scrollbars_update (shell); + gimp_display_shell_rulers_update (shell); +} + +/** + * gimp_display_shell_scroll_unoverscrollify: + * @shell: + * @in_offset_x: + * @in_offset_y: + * @out_offset_x: + * @out_offset_y: + * + * Takes a scroll offset and returns the offset that will not result + * in a scroll beyond the image border. If the image is already + * overscrolled, the return value is 0 for that given axis. + **/ +void +gimp_display_shell_scroll_unoverscrollify (GimpDisplayShell *shell, + gint in_offset_x, + gint in_offset_y, + gint *out_offset_x, + gint *out_offset_y) +{ + gint sw, sh; + gint out_offset_x_dummy, out_offset_y_dummy; + + g_return_if_fail (GIMP_IS_DISPLAY_SHELL (shell)); + + if (! out_offset_x) out_offset_x = &out_offset_x_dummy; + if (! out_offset_y) out_offset_y = &out_offset_y_dummy; + + *out_offset_x = in_offset_x; + *out_offset_y = in_offset_y; + + if (! shell->show_all) + { + gimp_display_shell_scale_get_image_size (shell, &sw, &sh); + + if (in_offset_x < 0) + { + *out_offset_x = MAX (in_offset_x, + MIN (0, 0 - shell->offset_x)); + } + else if (in_offset_x > 0) + { + gint min_offset = sw - shell->disp_width; + + *out_offset_x = MIN (in_offset_x, + MAX (0, min_offset - shell->offset_x)); + } + + if (in_offset_y < 0) + { + *out_offset_y = MAX (in_offset_y, + MIN (0, 0 - shell->offset_y)); + } + else if (in_offset_y > 0) + { + gint min_offset = sh - shell->disp_height; + + *out_offset_y = MIN (in_offset_y, + MAX (0, min_offset - shell->offset_y)); + } + } +} + +/** + * gimp_display_shell_scroll_center_image_xy: + * @shell: + * @image_x: + * @image_y: + * + * Center the viewport around the passed image coordinate + **/ +void +gimp_display_shell_scroll_center_image_xy (GimpDisplayShell *shell, + gdouble image_x, + gdouble image_y) +{ + gint viewport_x; + gint viewport_y; + + gimp_display_shell_transform_xy (shell, + image_x, image_y, + &viewport_x, &viewport_y); + + gimp_display_shell_scroll (shell, + viewport_x - shell->disp_width / 2, + viewport_y - shell->disp_height / 2); +} + +/** + * gimp_display_shell_scroll_center_image: + * @shell: + * @horizontally: + * @vertically: + * + * Centers the image in the display shell on the desired axes. + **/ +void +gimp_display_shell_scroll_center_image (GimpDisplayShell *shell, + gboolean horizontally, + gboolean vertically) +{ + gint image_x; + gint image_y; + gint image_width; + gint image_height; + gint center_x; + gint center_y; + gint offset_x = 0; + gint offset_y = 0; + + g_return_if_fail (GIMP_IS_DISPLAY_SHELL (shell)); + + if (! shell->display || + ! gimp_display_get_image (shell->display) || + (! vertically && ! horizontally)) + return; + + gimp_display_shell_scale_get_image_bounds (shell, + &image_x, &image_y, + &image_width, &image_height); + + if (shell->disp_width > image_width) + { + image_x -= (shell->disp_width - image_width) / 2; + image_width = shell->disp_width; + } + + if (shell->disp_height > image_height) + { + image_y -= (shell->disp_height - image_height) / 2; + image_height = shell->disp_height; + } + + center_x = image_x + image_width / 2; + center_y = image_y + image_height / 2; + + if (horizontally) + offset_x = center_x - shell->disp_width / 2 - shell->offset_x; + + if (vertically) + offset_y = center_y - shell->disp_height / 2 - shell->offset_y; + + gimp_display_shell_scroll (shell, offset_x, offset_y); +} + +/** + * gimp_display_shell_scroll_center_image: + * @shell: + * @horizontally: + * @vertically: + * + * Centers the image content in the display shell on the desired axes. + **/ +void +gimp_display_shell_scroll_center_content (GimpDisplayShell *shell, + gboolean horizontally, + gboolean vertically) +{ + gint content_x; + gint content_y; + gint content_width; + gint content_height; + gint center_x; + gint center_y; + gint offset_x = 0; + gint offset_y = 0; + + g_return_if_fail (GIMP_IS_DISPLAY_SHELL (shell)); + + if (! shell->display || + ! gimp_display_get_image (shell->display) || + (! vertically && ! horizontally)) + return; + + if (! gimp_display_shell_get_infinite_canvas (shell)) + { + gimp_display_shell_scale_get_image_bounds (shell, + &content_x, + &content_y, + &content_width, + &content_height); + } + else + { + gimp_display_shell_scale_get_image_bounding_box (shell, + &content_x, + &content_y, + &content_width, + &content_height); + } + + if (shell->disp_width > content_width) + { + content_x -= (shell->disp_width - content_width) / 2; + content_width = shell->disp_width; + } + + if (shell->disp_height > content_height) + { + content_y -= (shell->disp_height - content_height) / 2; + content_height = shell->disp_height; + } + + center_x = content_x + content_width / 2; + center_y = content_y + content_height / 2; + + if (horizontally) + offset_x = center_x - shell->disp_width / 2 - shell->offset_x; + + if (vertically) + offset_y = center_y - shell->disp_height / 2 - shell->offset_y; + + gimp_display_shell_scroll (shell, offset_x, offset_y); +} + +/** + * gimp_display_shell_scroll_get_scaled_viewport: + * @shell: + * @x: + * @y: + * @w: + * @h: + * + * Gets the viewport in screen coordinates, with origin at (0, 0) in + * the image. + **/ +void +gimp_display_shell_scroll_get_scaled_viewport (GimpDisplayShell *shell, + gint *x, + gint *y, + gint *w, + gint *h) +{ + g_return_if_fail (GIMP_IS_DISPLAY_SHELL (shell)); + + *x = shell->offset_x; + *y = shell->offset_y; + *w = shell->disp_width; + *h = shell->disp_height; +} + +/** + * gimp_display_shell_scroll_get_viewport: + * @shell: + * @x: + * @y: + * @w: + * @h: + * + * Gets the viewport in image coordinates. + **/ +void +gimp_display_shell_scroll_get_viewport (GimpDisplayShell *shell, + gdouble *x, + gdouble *y, + gdouble *w, + gdouble *h) +{ + g_return_if_fail (GIMP_IS_DISPLAY_SHELL (shell)); + + *x = shell->offset_x / shell->scale_x; + *y = shell->offset_y / shell->scale_y; + *w = shell->disp_width / shell->scale_x; + *h = shell->disp_height / shell->scale_y; +} |