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/* Copyright (c) 2015 imv authors
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, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include "viewport.h"
void imv_init_viewport(struct imv_viewport *view, SDL_Window *window)
{
view->window = window;
view->scale = 1;
view->x = view->y = view->fullscreen = view->redraw = 0;
view->playing = 1;
view->locked = 0;
}
void imv_destroy_viewport(struct imv_viewport *view)
{
view->window = NULL;
return;
}
void imv_viewport_toggle_fullscreen(struct imv_viewport *view)
{
if(view->fullscreen) {
SDL_SetWindowFullscreen(view->window, 0);
view->fullscreen = 0;
} else {
SDL_SetWindowFullscreen(view->window, SDL_WINDOW_FULLSCREEN_DESKTOP);
view->fullscreen = 1;
}
}
void imv_viewport_toggle_playing(struct imv_viewport *view)
{
view->playing = !view->playing;
}
void imv_viewport_scale_to_actual(struct imv_viewport *view, const struct imv_texture *tex)
{
view->scale = 1;
view->redraw = 1;
view->locked = 1;
imv_viewport_center(view, tex);
}
void imv_viewport_move(struct imv_viewport *view, int x, int y)
{
view->x += x;
view->y += y;
view->redraw = 1;
view->locked = 1;
}
void imv_viewport_zoom(struct imv_viewport *view, const struct imv_texture *tex, enum imv_zoom_source src, int amount)
{
double prev_scale = view->scale;
int x, y, ww, wh;
SDL_GetWindowSize(view->window, &ww, &wh);
/* x and y cordinates are relative to the image */
if(src == IMV_ZOOM_MOUSE) {
SDL_GetMouseState(&x, &y);
x -= view->x;
y -= view->y;
} else {
x = view->scale * tex->width / 2;
y = view->scale * tex->height / 2;
}
const int scaled_width = tex->width * view->scale;
const int scaled_height = tex->height * view->scale;
const int ic_x = view->x + scaled_width/2;
const int ic_y = view->y + scaled_height/2;
const int wc_x = ww/2;
const int wc_y = wh/2;
double delta_scale = 0.04 * ww * amount / tex->width;
view->scale += delta_scale;
const double min_scale = 0.1;
const double max_scale = 100;
if(view->scale > max_scale) {
view->scale = max_scale;
} else if (view->scale < min_scale) {
view->scale = min_scale;
}
if(view->scale < prev_scale) {
if(scaled_width < ww) {
x = scaled_width/2 - (ic_x - wc_x)*2;
}
if(scaled_height < wh) {
y = scaled_height/2 - (ic_y - wc_y)*2;
}
} else {
if(scaled_width < ww) {
x = scaled_width/2;
}
if(scaled_height < wh) {
y = scaled_height/2;
}
}
const double changeX = x - (x * (view->scale / prev_scale));
const double changeY = y - (y * (view->scale / prev_scale));
view->x += changeX;
view->y += changeY;
view->redraw = 1;
view->locked = 1;
}
void imv_viewport_center(struct imv_viewport *view, const struct imv_texture *tex)
{
int ww, wh;
SDL_GetWindowSize(view->window, &ww, &wh);
view->x = (ww - tex->width * view->scale) / 2;
view->y = (wh - tex->height * view->scale) / 2;
view->locked = 1;
view->redraw = 1;
}
void imv_viewport_scale_to_window(struct imv_viewport *view, const struct imv_texture *tex)
{
int ww, wh;
SDL_GetWindowSize(view->window, &ww, &wh);
double window_aspect = (double)ww / (double)wh;
double image_aspect = (double)tex->width / (double)tex->height;
if(window_aspect > image_aspect) {
/* Image will become too tall before it becomes too wide */
view->scale = (double)wh / (double)tex->height;
} else {
/* Image will become too wide before it becomes too tall */
view->scale = (double)ww / (double)tex->width;
}
imv_viewport_center(view, tex);
view->locked = 0;
}
void imv_viewport_set_redraw(struct imv_viewport *view)
{
view->redraw = 1;
}
void imv_viewport_set_title(struct imv_viewport *view, char* title)
{
SDL_SetWindowTitle(view->window, title);
}
void imv_viewport_update(struct imv_viewport *view, struct imv_texture *tex)
{
view->redraw = 1;
if(view->locked) {
return;
}
imv_viewport_center(view, tex);
imv_viewport_scale_to_window(view, tex);
}
int imv_viewport_needs_redraw(struct imv_viewport *view)
{
int redraw = 0;
if(view->redraw) {
redraw = 1;
view->redraw = 0;
}
return redraw;
}
/* vim:set ts=2 sts=2 sw=2 et: */
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