1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
|
/* 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"
struct imv_viewport *imv_viewport_create(SDL_Window *window)
{
struct imv_viewport *view = malloc(sizeof(struct imv_viewport));
view->window = window;
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_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: */
|