For when merging points. Based on CC Attribution 3.0 sound by "stinkhorn" (see CHANGES.txt & AUTHORS.txt).
647 lines
17 KiB
C
647 lines
17 KiB
C
/* polyfill.c
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A Magic tool for Tux Paint that creates a filled polygon.
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by Bill Kendrick <bill@newbreedsoftware.com>
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with help from Pere Pujal Carabantes
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Scanline polygon fill routine based on public-domain code
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by Darel Rex Finley, 2007 <https://alienryderflex.com/polygon_fill/>
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Last updated: May 28, 2024
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*/
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#include <stdio.h>
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#include <string.h>
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#include <libintl.h>
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#include "tp_magic_api.h"
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#include "SDL_image.h"
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#include "SDL_mixer.h"
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enum
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{
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TOOL_POLYFILL,
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NUM_TOOLS
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};
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char *polyfill_names[NUM_TOOLS] = {
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gettext_noop("Filled Polygon"),
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};
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char *polyfill_descr[NUM_TOOLS] = {
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gettext_noop
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("Click multiple times in your picture to create a filled polygon. You may drag control points to alter the shape. Click the first point to complete the shape."),
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};
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char *polyfill_icon_filenames[NUM_TOOLS] = {
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"polyfill.png",
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};
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enum {
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SND_PLACE,
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SND_MOVE,
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SND_REMOVE,
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SND_NEARBY,
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SND_FINISH,
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NUM_SOUNDS
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};
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char *polyfill_snd_filenames[NUM_SOUNDS] = {
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"polyfill_place.ogg",
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"polyfill_move.ogg",
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"polyfill_remove.ogg",
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"polyfill_nearby.ogg",
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"polyfill_finish.ogg",
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};
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#define SNAP_SIZE 16
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#define MAX_PTS 17
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SDL_Surface *polyfill_snapshot = NULL;
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int polyfill_pt_x[MAX_PTS];
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int polyfill_pt_y[MAX_PTS];
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int polyfill_num_pts = 0;
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int polyfill_editing = MAX_PTS;
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int polyfill_dragged = 0;
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int polyfill_active = 0;
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Mix_Chunk *snd_effects[NUM_SOUNDS];
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Uint32 polyfill_color, polyfill_color_red, polyfill_color_green;
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Uint32 polyfill_api_version(void);
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int polyfill_init(magic_api * api, Uint8 disabled_features, Uint8 complexity_level);
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int polyfill_get_tool_count(magic_api * api);
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SDL_Surface *polyfill_get_icon(magic_api * api, int which);
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char *polyfill_get_name(magic_api * api, int which);
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int polyfill_get_group(magic_api * api, int which);
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int polyfill_get_order(int which);
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char *polyfill_get_description(magic_api * api, int which, int mode);
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int polyfill_requires_colors(magic_api * api, int which);
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int polyfill_modes(magic_api * api, int which);
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Uint8 polyfill_accepted_sizes(magic_api * api, int which, int mode);
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Uint8 polyfill_default_size(magic_api * api, int which, int mode);
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void polyfill_shutdown(magic_api * api);
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void
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polyfill_click(magic_api * api, int which, int mode,
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SDL_Surface * canvas, SDL_Surface * snapshot, int x, int y, SDL_Rect * update_rect);
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void
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polyfill_drag(magic_api * api, int which,
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SDL_Surface * canvas, SDL_Surface * snapshot, int old_x, int old_y, int x, int y, SDL_Rect * update_rect);
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void
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polyfill_release(magic_api * api, int which,
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SDL_Surface * canvas, SDL_Surface * snapshot, int x, int y, SDL_Rect * update_rect);
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void polyfill_set_color(magic_api * api, int which, SDL_Surface * canvas, SDL_Surface * snapshot, Uint8 r, Uint8 g,
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Uint8 b, SDL_Rect * update_rect);
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void polyfill_set_size(magic_api * api, int which, int mode, SDL_Surface * canvas, SDL_Surface * snapshot, Uint8 size,
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SDL_Rect * update_rect);
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void polyfill_line_callback(void *pointer, int which, SDL_Surface * canvas, SDL_Surface * snapshot, int x, int y);
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void
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polyfill_release(magic_api * api, int which,
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SDL_Surface * canvas, SDL_Surface * snapshot, int x, int y, SDL_Rect * update_rect);
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void polyfill_switchin(magic_api * api, int which, int mode, SDL_Surface * canvas);
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void polyfill_switchout(magic_api * api, int which, int mode, SDL_Surface * canvas);
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void polyfill_draw_preview(magic_api * api, SDL_Surface * canvas, int show_handles);
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void polyfill_draw_final(SDL_Surface * canvas);
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Uint32 polyfill_api_version(void)
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{
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return (TP_MAGIC_API_VERSION);
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}
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int polyfill_init(magic_api * api, Uint8 disabled_features ATTRIBUTE_UNUSED, Uint8 complexity_level ATTRIBUTE_UNUSED)
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{
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int i;
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char filename[1024];
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for (i = 0; i < NUM_SOUNDS; i++)
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{
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snprintf(filename, sizeof(filename), "%ssounds/magic/%s", api->data_directory, polyfill_snd_filenames[i]);
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snd_effects[i] = Mix_LoadWAV(filename);
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}
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return (1);
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}
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int polyfill_get_tool_count(magic_api * api ATTRIBUTE_UNUSED)
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{
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return NUM_TOOLS;
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}
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SDL_Surface *polyfill_get_icon(magic_api * api, int which ATTRIBUTE_UNUSED)
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{
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char filename[1024];
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snprintf(filename, sizeof(filename), "%simages/magic/%s", api->data_directory, polyfill_icon_filenames[which]);
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return (IMG_Load(filename));
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}
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char *polyfill_get_name(magic_api * api ATTRIBUTE_UNUSED, int which)
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{
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return strdup(gettext(polyfill_names[which]));
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}
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int polyfill_get_group(magic_api * api ATTRIBUTE_UNUSED, int which ATTRIBUTE_UNUSED)
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{
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return MAGIC_TYPE_ARTISTIC;
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}
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int polyfill_get_order(int which)
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{
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return 610 + which; // FIXME
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}
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char *polyfill_get_description(magic_api * api ATTRIBUTE_UNUSED, int which, int mode ATTRIBUTE_UNUSED)
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{
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return strdup(gettext(polyfill_descr[which]));
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}
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int polyfill_requires_colors(magic_api * api ATTRIBUTE_UNUSED, int which ATTRIBUTE_UNUSED)
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{
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return 1;
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}
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int polyfill_modes(magic_api * api ATTRIBUTE_UNUSED, int which ATTRIBUTE_UNUSED)
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{
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return MODE_PAINT;
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}
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Uint8 polyfill_accepted_sizes(magic_api * api ATTRIBUTE_UNUSED, int which ATTRIBUTE_UNUSED, int mode ATTRIBUTE_UNUSED)
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{
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return 1;
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}
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Uint8 polyfill_default_size(magic_api * api ATTRIBUTE_UNUSED, int which ATTRIBUTE_UNUSED, int mode ATTRIBUTE_UNUSED)
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{
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return 1;
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}
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void polyfill_shutdown(magic_api * api ATTRIBUTE_UNUSED)
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{
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int i;
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for (i = 0; i < NUM_SOUNDS; i++)
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{
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if (snd_effects[i] != NULL)
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{
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Mix_FreeChunk(snd_effects[i]);
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}
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}
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if (polyfill_snapshot != NULL)
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{
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SDL_FreeSurface(polyfill_snapshot);
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polyfill_snapshot = NULL;
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}
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}
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void
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polyfill_click(magic_api * api, int which ATTRIBUTE_UNUSED, int mode ATTRIBUTE_UNUSED,
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SDL_Surface * canvas, SDL_Surface * snapshot, int x, int y, SDL_Rect * update_rect)
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{
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int i;
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polyfill_dragged = 0;
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#ifdef DEBUG
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printf("Click. num_pts = %d\n", polyfill_num_pts);
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#endif
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/* See if we're clicking a pre-existing point, to edit it? */
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polyfill_editing = MAX_PTS;
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for (i = 0; i < polyfill_num_pts && polyfill_editing == MAX_PTS; i++)
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{
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if (abs(x - polyfill_pt_x[i]) <= SNAP_SIZE && abs(y - polyfill_pt_y[i]) <= SNAP_SIZE)
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{
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polyfill_editing = i;
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}
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}
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if (polyfill_editing != MAX_PTS)
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{
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#ifdef DEBUG
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printf("Clicked %d to edit it\n", polyfill_editing);
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#endif
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polyfill_draw_preview(api, canvas, 1);
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return;
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}
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/* Trying to add a new point? */
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if (polyfill_num_pts < MAX_PTS)
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{
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#ifdef DEBUG
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printf("Adding new point %d\n", polyfill_num_pts);
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#endif
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polyfill_pt_x[polyfill_num_pts] = x;
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polyfill_pt_y[polyfill_num_pts] = y;
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polyfill_editing = polyfill_num_pts;
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polyfill_num_pts++;
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/* Add the new point */
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polyfill_drag(api, which, canvas, snapshot, x, y, x, y, update_rect);
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api->playsound(snd_effects[SND_PLACE], (x * 255) / canvas->w, 255);
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}
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else
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{
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/* Out of points! */
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#ifdef DEBUG
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printf("Out of space for new points!\n");
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#endif
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}
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}
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void
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polyfill_drag(magic_api * api, int which ATTRIBUTE_UNUSED,
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SDL_Surface * canvas, SDL_Surface * snapshot ATTRIBUTE_UNUSED, int old_x ATTRIBUTE_UNUSED,
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int old_y ATTRIBUTE_UNUSED, int x, int y, SDL_Rect * update_rect)
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{
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polyfill_dragged = 1;
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if (polyfill_editing >= MAX_PTS)
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return;
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polyfill_pt_x[polyfill_editing] = x;
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polyfill_pt_y[polyfill_editing] = y;
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polyfill_draw_preview(api, canvas, 1);
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if (polyfill_editing == polyfill_num_pts - 1 &&
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polyfill_num_pts >= 3 &&
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x >= polyfill_pt_x[0] - SNAP_SIZE &&
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x <= polyfill_pt_x[0] + SNAP_SIZE &&
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y >= polyfill_pt_y[0] - SNAP_SIZE &&
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y <= polyfill_pt_y[0] + SNAP_SIZE) {
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/* If placing/moving the final (red) point, and it's
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near the initial (green) point, play an electrostatic sound */
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api->playsound(snd_effects[SND_NEARBY], (x * 255) / canvas->w, 255);
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} else if (polyfill_editing == 0 &&
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polyfill_num_pts >= 3 &&
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x >= polyfill_pt_x[polyfill_num_pts - 1] - SNAP_SIZE &&
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x <= polyfill_pt_x[polyfill_num_pts - 1] + SNAP_SIZE &&
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y >= polyfill_pt_y[polyfill_num_pts - 1] - SNAP_SIZE &&
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y <= polyfill_pt_y[polyfill_num_pts - 1] + SNAP_SIZE) {
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/* If moving the initial (green) point, and it's
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near the final (red) point, also play an electrostatic sound */
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api->playsound(snd_effects[SND_NEARBY], (x * 255) / canvas->w, 255);
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} else {
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/* Otherwise, play the normal "moving a point" sound */
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api->playsound(snd_effects[SND_MOVE], (x * 255) / canvas->w, 255);
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}
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update_rect->x = 0;
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update_rect->y = 0;
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update_rect->w = canvas->w;
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update_rect->h = canvas->h;
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}
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void polyfill_draw_preview(magic_api * api, SDL_Surface * canvas, int show_handles)
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{
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int i, xx, yy;
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SDL_Rect dest;
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if (polyfill_snapshot == NULL)
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return;
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SDL_BlitSurface(polyfill_snapshot, NULL, canvas, NULL);
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if (show_handles)
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{
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for (i = 1; i < polyfill_num_pts - 1; i++)
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{
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for (yy = -4; yy <= 4; yy++)
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{
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for (xx = -4; xx <= 4; xx++)
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{
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api->xorpixel(canvas, polyfill_pt_x[i] + xx, polyfill_pt_y[i] + yy);
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}
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}
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}
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if (polyfill_num_pts > 0)
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{
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dest.x = polyfill_pt_x[0] - SNAP_SIZE;
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dest.y = polyfill_pt_y[0] - SNAP_SIZE;
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dest.w = SNAP_SIZE * 2;
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dest.h = SNAP_SIZE * 2;
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SDL_FillRect(canvas, &dest, polyfill_color_green);
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}
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if (polyfill_num_pts > 1)
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{
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dest.x = polyfill_pt_x[polyfill_num_pts - 1] - SNAP_SIZE;
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dest.y = polyfill_pt_y[polyfill_num_pts - 1] - SNAP_SIZE;
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dest.w = SNAP_SIZE * 2;
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dest.h = SNAP_SIZE * 2;
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SDL_FillRect(canvas, &dest, polyfill_color_red);
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}
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}
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for (i = 0; i < polyfill_num_pts - 1; i++)
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{
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api->line((void *)api, 0 /* which */ , canvas, NULL /* snapshot */ ,
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polyfill_pt_x[i], polyfill_pt_y[i],
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polyfill_pt_x[i + 1], polyfill_pt_y[i + 1], 1, polyfill_line_callback);
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}
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//SDL_UpdateRect(canvas, 0, 0, canvas->w, canvas->h);
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}
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void
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polyfill_release(magic_api * api, int which ATTRIBUTE_UNUSED,
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SDL_Surface * canvas, SDL_Surface * snapshot ATTRIBUTE_UNUSED, int x, int y,
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SDL_Rect * update_rect ATTRIBUTE_UNUSED)
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{
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int i;
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if (polyfill_snapshot == NULL)
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return;
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if (polyfill_editing >= MAX_PTS)
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return;
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#ifdef DEBUG
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printf("Release while editing %d\n", polyfill_editing);
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#endif
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/* If they simply clicked the first point (without
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drawing to move it), and there are enough points, consider
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it a final placement of a new point! */
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if (polyfill_editing == 0 && polyfill_dragged == 0 && polyfill_num_pts > 2 && polyfill_num_pts < MAX_PTS)
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{
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#ifdef DEBUG
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printf("Clicked first point to end polygon!\n");
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#endif
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polyfill_pt_x[polyfill_num_pts] = polyfill_pt_x[0];
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polyfill_pt_y[polyfill_num_pts] = polyfill_pt_y[0];
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polyfill_editing = polyfill_num_pts;
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polyfill_num_pts++;
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}
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/* Moved (or placed) the final spot at the beginning? */
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if (polyfill_num_pts > 2 &&
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((polyfill_editing == polyfill_num_pts - 1 &&
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abs(x - polyfill_pt_x[0]) <= SNAP_SIZE &&
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abs(y - polyfill_pt_y[0]) <= SNAP_SIZE) ||
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(polyfill_editing == 0 &&
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abs(x - polyfill_pt_x[polyfill_num_pts - 1]) <= SNAP_SIZE &&
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abs(y - polyfill_pt_y[polyfill_num_pts - 1]) <= SNAP_SIZE)))
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{
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#ifdef DEBUG
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printf("Ending the polygon!\n");
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#endif
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/* Snap the points */
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if (polyfill_editing == 0)
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{
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polyfill_pt_x[0] = polyfill_pt_x[polyfill_num_pts - 1];
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polyfill_pt_y[0] = polyfill_pt_y[polyfill_num_pts - 1];
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}
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else
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{
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polyfill_pt_x[polyfill_num_pts - 1] = polyfill_pt_x[0];
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polyfill_pt_y[polyfill_num_pts - 1] = polyfill_pt_y[0];
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}
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polyfill_draw_final(canvas);
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/* Reset points */
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polyfill_num_pts = 0;
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polyfill_editing = MAX_PTS;
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/* Update snapshot ahead of next polygon */
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SDL_BlitSurface(canvas, NULL, polyfill_snapshot, NULL);
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/* Play "finish" sound effect */
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api->playsound(snd_effects[SND_FINISH], 128 /* TODO could be clever and determine midpoint of polygon */, 255);
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}
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else
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{
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/* Did not move (or place) the final spot at the beginning */
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/* Did we stick to points together? We can merge them */
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if (polyfill_num_pts > 2)
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{
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int to_merge = MAX_PTS;
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for (i = polyfill_editing - 1; i < polyfill_editing + 1; i++)
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{
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if (i >= 0 && i < polyfill_num_pts - 1)
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{
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if (abs(polyfill_pt_x[i] - polyfill_pt_x[i + 1]) <= SNAP_SIZE &&
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abs(polyfill_pt_y[i] - polyfill_pt_y[i + 1]) <= SNAP_SIZE)
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{
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#ifdef DEBUG
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printf("%d & %d can be merged\n", i, i + 1);
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#endif
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to_merge = i;
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}
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}
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}
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if (to_merge != MAX_PTS)
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{
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#ifdef DEBUG
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printf("Merging %d with %d\n", to_merge, to_merge + 1);
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#endif
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for (i = to_merge; i < polyfill_num_pts - 1; i++)
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{
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polyfill_pt_x[i] = polyfill_pt_x[i + 1];
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polyfill_pt_y[i] = polyfill_pt_y[i + 1];
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}
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polyfill_num_pts--;
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/* Play "remove" sound effect */
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api->playsound(snd_effects[SND_REMOVE], (x * 255) / canvas->w, 255);
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}
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}
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polyfill_draw_preview(api, canvas, 1);
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}
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update_rect->x = 0;
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update_rect->y = 0;
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update_rect->w = canvas->w;
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update_rect->h = canvas->h;
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}
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void polyfill_set_color(magic_api * api, int which ATTRIBUTE_UNUSED, SDL_Surface * canvas,
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SDL_Surface * snapshot ATTRIBUTE_UNUSED, Uint8 r, Uint8 g, Uint8 b, SDL_Rect * update_rect)
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{
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polyfill_color = SDL_MapRGB(canvas->format, r, g, b);
|
|
|
|
if (polyfill_active)
|
|
{
|
|
polyfill_draw_preview(api, canvas, 1);
|
|
update_rect->x = 0;
|
|
update_rect->y = 0;
|
|
update_rect->w = canvas->w;
|
|
update_rect->h = canvas->h;
|
|
}
|
|
}
|
|
|
|
void polyfill_set_size(magic_api * api ATTRIBUTE_UNUSED, int which ATTRIBUTE_UNUSED, int mode ATTRIBUTE_UNUSED,
|
|
SDL_Surface * canvas ATTRIBUTE_UNUSED, SDL_Surface * snapshot ATTRIBUTE_UNUSED,
|
|
Uint8 size ATTRIBUTE_UNUSED, SDL_Rect * update_rect ATTRIBUTE_UNUSED)
|
|
{
|
|
}
|
|
|
|
|
|
void polyfill_line_callback(void *pointer ATTRIBUTE_UNUSED, int which ATTRIBUTE_UNUSED, SDL_Surface * canvas,
|
|
SDL_Surface * snapshot ATTRIBUTE_UNUSED, int x, int y)
|
|
{
|
|
SDL_Rect dest;
|
|
|
|
dest.x = x - 1;
|
|
dest.y = y - 1;
|
|
dest.w = 3;
|
|
dest.h = 3;
|
|
|
|
SDL_FillRect(canvas, &dest, polyfill_color);
|
|
}
|
|
|
|
|
|
void polyfill_switchin(magic_api * api ATTRIBUTE_UNUSED, int which ATTRIBUTE_UNUSED, int mode ATTRIBUTE_UNUSED,
|
|
SDL_Surface * canvas)
|
|
{
|
|
polyfill_color_red = SDL_MapRGB(canvas->format, 255, 0, 0);
|
|
polyfill_color_green = SDL_MapRGB(canvas->format, 0, 255, 0);
|
|
|
|
if (polyfill_snapshot == NULL)
|
|
{
|
|
polyfill_snapshot = SDL_CreateRGBSurface(SDL_SWSURFACE, canvas->w, canvas->h,
|
|
canvas->format->BitsPerPixel, canvas->format->Rmask,
|
|
canvas->format->Gmask, canvas->format->Bmask, canvas->format->Amask);
|
|
}
|
|
|
|
if (polyfill_snapshot != NULL)
|
|
{
|
|
SDL_BlitSurface(canvas, NULL, polyfill_snapshot, NULL);
|
|
}
|
|
|
|
polyfill_active = 1;
|
|
}
|
|
|
|
void polyfill_switchout(magic_api * api ATTRIBUTE_UNUSED, int which ATTRIBUTE_UNUSED, int mode ATTRIBUTE_UNUSED,
|
|
SDL_Surface * canvas)
|
|
{
|
|
polyfill_num_pts = 0;
|
|
polyfill_editing = MAX_PTS;
|
|
polyfill_active = 0;
|
|
|
|
if (polyfill_snapshot != NULL)
|
|
{
|
|
SDL_BlitSurface(polyfill_snapshot, NULL, canvas, NULL);
|
|
}
|
|
}
|
|
|
|
/* Based on public-domain code by Darel Rex Finley, 2007
|
|
https://alienryderflex.com/polygon_fill/
|
|
*/
|
|
void polyfill_draw_final(SDL_Surface * canvas)
|
|
{
|
|
int i, j, ymin, ymax, y, nodes, swap;
|
|
int nodeX[256];
|
|
SDL_Rect rect;
|
|
|
|
SDL_BlitSurface(polyfill_snapshot, NULL, canvas, NULL);
|
|
|
|
ymin = canvas->w;
|
|
ymax = 0;
|
|
for (i = 0; i < polyfill_num_pts; i++)
|
|
{
|
|
if (polyfill_pt_y[i] < ymin)
|
|
{
|
|
ymin = polyfill_pt_y[i];
|
|
}
|
|
if (polyfill_pt_y[i] > ymax)
|
|
{
|
|
ymax = polyfill_pt_y[i];
|
|
}
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
printf("ymin %d -> ymax %d\n", ymin, ymax);
|
|
#endif
|
|
|
|
for (y = ymin; y <= ymax; y++)
|
|
{
|
|
nodes = 0;
|
|
j = polyfill_num_pts - 2;
|
|
|
|
for (i = 0; i < polyfill_num_pts - 1; i++)
|
|
{
|
|
if ((polyfill_pt_y[i] < y && polyfill_pt_y[j] >= y) || (polyfill_pt_y[j] < y && polyfill_pt_y[i] >= y))
|
|
{
|
|
nodeX[nodes++] = (int)
|
|
((double)polyfill_pt_x[i] +
|
|
(double)(y - polyfill_pt_y[i]) /
|
|
(double)(polyfill_pt_y[j] - polyfill_pt_y[i]) * (double)(polyfill_pt_x[j] - polyfill_pt_x[i]));
|
|
}
|
|
|
|
j = i;
|
|
}
|
|
|
|
// Sort the nodes, via a simple “Bubble” sort.
|
|
i = 0;
|
|
while (i < nodes - 1)
|
|
{
|
|
if (nodeX[i] > nodeX[i + 1])
|
|
{
|
|
swap = nodeX[i];
|
|
nodeX[i] = nodeX[i + 1];
|
|
nodeX[i + 1] = swap;
|
|
if (i)
|
|
i--;
|
|
}
|
|
else
|
|
{
|
|
i++;
|
|
}
|
|
}
|
|
|
|
// Fill the pixels between node pairs.
|
|
for (i = 0; i < nodes; i += 2)
|
|
{
|
|
if (nodeX[i] >= canvas->w)
|
|
break;
|
|
|
|
if (nodeX[i + 1] > 0)
|
|
{
|
|
if (nodeX[i] < 0)
|
|
nodeX[i] = 0;
|
|
if (nodeX[i + 1] > canvas->w - 1)
|
|
nodeX[i + 1] = canvas->w - 1;
|
|
|
|
rect.x = nodeX[i];
|
|
rect.y = y;
|
|
rect.w = nodeX[i + 1] - nodeX[i] + 1;
|
|
rect.h = 1;
|
|
SDL_FillRect(canvas, &rect, polyfill_color);
|
|
}
|
|
}
|
|
}
|
|
}
|