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#include "viewport.h"
struct imv_viewport {
SDL_Window *window;
SDL_Renderer *renderer;
double scale;
int x, y;
int fullscreen;
int redraw;
int playing;
int locked;
};
static void input_xy_to_render_xy(struct imv_viewport *view, int *x, int *y)
{
int ww, wh, rw, rh;
SDL_GetWindowSize(view->window, &ww, &wh);
SDL_GetRendererOutputSize(view->renderer, &rw, &rh);
*x *= rw / ww;
*y *= rh / wh;
}
struct imv_viewport *imv_viewport_create(SDL_Window *window, SDL_Renderer *renderer)
{
struct imv_viewport *view = malloc(sizeof *view);
view->window = window;
view->renderer = renderer;
view->scale = 1;
view->x = view->y = view->fullscreen = view->redraw = 0;
view->playing = 1;
view->locked = 0;
return view;
}
void imv_viewport_free(struct imv_viewport *view)
{
free(view);
}
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_set_playing(struct imv_viewport *view, bool playing)
{
view->playing = playing;
}
bool imv_viewport_is_playing(struct imv_viewport *view)
{
return view->playing;
}
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_image *image)
{
view->scale = 1;
view->redraw = 1;
view->locked = 1;
imv_viewport_center(view, image);
}
void imv_viewport_get_offset(struct imv_viewport *view, int *x, int *y)
{
if(x) {
*x = view->x;
}
if(y) {
*y = view->y;
}
}
void imv_viewport_get_scale(struct imv_viewport *view, double *scale)
{
if(scale) {
*scale = view->scale;
}
}
void imv_viewport_move(struct imv_viewport *view, int x, int y,
const struct imv_image *image)
{
input_xy_to_render_xy(view, &x, &y);
view->x += x;
view->y += y;
view->redraw = 1;
view->locked = 1;
int w = (int)(imv_image_width(image) * view->scale);
int h = (int)(imv_image_height(image) * view->scale);
int ww, wh;
SDL_GetRendererOutputSize(view->renderer, &ww, &wh);
if (view->x < -w) {
view->x = -w;
}
if (view->x > ww) {
view->x = ww;
}
if (view->y < -h) {
view->y = -h;
}
if (view->y > wh) {
view->y = wh;
}
}
void imv_viewport_zoom(struct imv_viewport *view, const struct imv_image *image, enum imv_zoom_source src, int amount)
{
double prev_scale = view->scale;
int x, y, ww, wh;
SDL_GetRendererOutputSize(view->renderer, &ww, &wh);
const int image_width = imv_image_width(image);
const int image_height = imv_image_height(image);
/* x and y cordinates are relative to the image */
if(src == IMV_ZOOM_MOUSE) {
SDL_GetMouseState(&x, &y);
input_xy_to_render_xy(view, &x, &y);
x -= view->x;
y -= view->y;
} else {
x = view->scale * image_width / 2;
y = view->scale * image_height / 2;
}
const int scaled_width = image_width * view->scale;
const int scaled_height = image_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 / image_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_image *image)
{
int ww, wh;
SDL_GetRendererOutputSize(view->renderer, &ww, &wh);
const int image_width = imv_image_width(image);
const int image_height = imv_image_height(image);
view->x = (ww - image_width * view->scale) / 2;
view->y = (wh - image_height * view->scale) / 2;
view->locked = 1;
view->redraw = 1;
}
void imv_viewport_scale_to_window(struct imv_viewport *view, const struct imv_image *image)
{
int ww, wh;
SDL_GetRendererOutputSize(view->renderer, &ww, &wh);
const int image_width = imv_image_width(image);
const int image_height = imv_image_height(image);
const double window_aspect = (double)ww / (double)wh;
const double image_aspect = (double)image_width / (double)image_height;
if(window_aspect > image_aspect) {
/* Image will become too tall before it becomes too wide */
view->scale = (double)wh / (double)image_height;
} else {
/* Image will become too wide before it becomes too tall */
view->scale = (double)ww / (double)image_width;
}
imv_viewport_center(view, image);
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_image *image)
{
view->redraw = 1;
if(view->locked) {
return;
}
imv_viewport_center(view, image);
imv_viewport_scale_to_window(view, image);
}
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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