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
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
|
#include "../../include/mgui/scrollview.h"
#include "../../include/mgui/mgui.h"
#include "../../include/alloc.h"
#include "../../include/common.h"
#include <mgl/mgl.h>
#include <mgl/window/window.h>
#include <mgl/window/event.h>
#include <mgl/graphics/rectangle.h>
#include <limits.h>
#include <assert.h>
#include <stdio.h>
#define SCROLL_ACCEL 20.0f
#define SCROLL_DEACCEL 10.0f
#define WIDGET_NATURAL_SIZE INT_MAX
static float max_float(float a, float b) {
return a >= b ? a : b;
}
static int max_int(int a, int b) {
return a >= b ? a : b;
}
static int min_int(int a, int b) {
return a <= b ? a : b;
}
static float abs_float(float value) {
return value >= 0.0f ? value : -value;
}
mgui_scrollview* mgui_scrollview_create(void) {
mgui_scrollview *scrollview = mgui_alloc(sizeof(mgui_scrollview));
mgui_widget_init(&scrollview->widget, MGUI_WIDGET_SCROLLVIEW);
scrollview->child = NULL;
scrollview->position = (mgl_vec2i){ 0, 0 };
scrollview->scroll = (mgl_vec2i){ 0, 0 };
scrollview->mouse_scroll = (mgl_vec2f){ 0.0f, 0.0f };
scrollview->scrollbar_pos = (mgl_vec2f){ 0.0f, 0.0f };
scrollview->scrollbar_size = (mgl_vec2f){ 0.0f, 0.0f };
scrollview->scrollbar_move_prev_pos = (mgl_vec2f){ 0.0f, 0.0f };
scrollview->moving_scrollbar = false;
return scrollview;
}
void mgui_scrollview_destroy(mgui_scrollview *scrollview) {
if(scrollview->child)
mgui_widget_destroy(scrollview->child);
mgui_free(scrollview);
}
mgui_widget* mgui_scrollview_to_widget(mgui_scrollview *list) {
return &list->widget;
}
mgui_scrollview* mgui_widget_to_scrollview(mgui_widget *widget) {
assert(widget->type == MGUI_WIDGET_SCROLLVIEW);
return (mgui_scrollview*)widget;
}
void mgui_scrollview_set_child(mgui_scrollview *self, mgui_widget *child) {
assert(child != mgui_scrollview_to_widget(self));
self->child = child;
if(self->child) {
mgui_widget_set_has_parent(self->child);
mgui_widget_calculate_size(self->child, self->widget.size);
}
}
void mgui_scrollview_set_position(mgui_scrollview *self, mgl_vec2i position) {
self->position = position;
}
void mgui_scrollview_calculate_size(mgui_scrollview *self, mgl_vec2i max_size) {
self->widget.size = max_size;
if(self->widget.size.x >= WIDGET_NATURAL_SIZE/2 || self->widget.size.y >= WIDGET_NATURAL_SIZE/2) {
self->widget.size.x = 500;
self->widget.size.y = 600;
}
/* TODO: this assumes child list uses vertical scroll. Make this work for horizontal scroll as well */
if(self->child)
mgui_widget_calculate_size(self->child, (mgl_vec2i){ max_size.x, WIDGET_NATURAL_SIZE });
}
void mgui_scrollview_on_event(mgui_scrollview *self, mgl_window *window, mgl_event *event) {
/* TODO: Allow keyboard navigation if scrollview has focus */
if(event->type == MGL_EVENT_MOUSE_WHEEL_SCROLLED)
self->mouse_scroll.y += (event->mouse_wheel_scroll.delta * SCROLL_ACCEL);
if(event->type == MGL_EVENT_MOUSE_BUTTON_PRESSED
&& event->mouse_button.button == MGL_BUTTON_LEFT
&& mgui_rectangle_contains(self->scrollbar_pos, self->scrollbar_size, (mgl_vec2f){ event->mouse_button.x, event->mouse_button.y }))
{
self->moving_scrollbar = true;
self->scrollbar_move_prev_pos = (mgl_vec2f){ event->mouse_button.x, event->mouse_button.y };
} else if(event->type == MGL_EVENT_MOUSE_BUTTON_RELEASED && event->mouse_button.button == MGL_BUTTON_LEFT) {
self->moving_scrollbar = false;
}
if(self->child)
mgui_widget_on_event(self->child, window, event);
}
static void mgui_scrollview_handle_scrollbar_move(mgui_scrollview *self, mgl_window *window, double scrollbar_height_ratio) {
if(mgl_window_is_mouse_button_pressed(window, MGL_BUTTON_LEFT) && self->moving_scrollbar) {
mgl_vec2f mouse_move_diff = (mgl_vec2f){
window->cursor_position.x - self->scrollbar_move_prev_pos.x,
window->cursor_position.y - self->scrollbar_move_prev_pos.y
};
self->scrollbar_move_prev_pos.x = window->cursor_position.x;
self->scrollbar_move_prev_pos.y = window->cursor_position.y;
/* TODO: Handle vertical scrollbar once its added */
/* TODO: Not perfect, improve */
if(scrollbar_height_ratio != 0.0)
self->scroll.y -= (mouse_move_diff.y * (1.0/scrollbar_height_ratio));
}
}
static void mgui_scrollview_draw_child(mgui_scrollview *self, mgl_window *window, double margin_width, double margin_height, double height, double scrollbar_height, mgl_vec2i child_size) {
if(!self->child)
return;
mgl_scissor prev_scissor;
mgl_window_get_scissor(window, &prev_scissor);
mgl_scissor new_scissor = {
.position = self->position,
.size = (mgl_vec2i){ self->widget.size.x - margin_width, self->widget.size.y - margin_height }
};
mgl_window_set_scissor(window, &new_scissor);
mgui_widget_set_position(self->child,
(mgl_vec2i){ self->position.x + self->scroll.x + self->child->margin.left, self->position.y + self->scroll.y + self->child->margin.top });
mgui_widget_draw(self->child, window);
mgl_window_set_scissor(window, &prev_scissor);
{
const double scroll_ratio = child_size.y == 0 ? 0.0 : (double)-self->scroll.y / (double)child_size.y;
const int scrollbar_offset_y = height * scroll_ratio;
const int scrollbar_width = 10;
const int right = self->widget.size.x - self->widget.margin.left - self->widget.margin.right;
self->scrollbar_pos = (mgl_vec2f){ self->position.x + right - scrollbar_width, self->position.y + scrollbar_offset_y };
self->scrollbar_size = (mgl_vec2f){ scrollbar_width, scrollbar_height };
mgl_rectangle rect = {
.position = self->scrollbar_pos,
.size = self->scrollbar_size,
.color = { 55, 60, 68, 255 }
};
mgl_rectangle_draw(mgl_get_context(), &rect);
}
}
static void mgui_scrollview_limit_scroll_to_child_size(mgui_scrollview *self, mgl_vec2i child_size) {
if(child_size.x > self->widget.size.x) {
self->scroll.x = min_int(self->scroll.x, 0);
self->scroll.x = max_int(self->scroll.x, -child_size.x + self->widget.size.x);
} else {
self->scroll.x = 0;
}
if(child_size.y > self->widget.size.y) {
self->scroll.y = min_int(self->scroll.y, 0);
self->scroll.y = max_int(self->scroll.y, -child_size.y + self->widget.size.y);
} else {
self->scroll.y = 0;
}
}
static void mgui_scrollview_update_mouse_scroll(mgui_scrollview *self, double frame_time) {
self->mouse_scroll.x *= max_float(0.0f, (1.0f - frame_time * SCROLL_DEACCEL));
self->mouse_scroll.y *= max_float(0.0f, (1.0f - frame_time * SCROLL_DEACCEL));
if(abs_float(self->mouse_scroll.x) < 0.0001f)
self->mouse_scroll.x = 0.0f;
if(abs_float(self->mouse_scroll.y) < 0.0001f)
self->mouse_scroll.y = 0.0f;
self->scroll.x += (int)self->mouse_scroll.x;
self->scroll.y += (int)self->mouse_scroll.y;
}
/* TODO: Check if visible in scissor */
void mgui_scrollview_draw(mgui_scrollview *self, mgl_window *window) {
const double frame_time = mgui_get_frame_time_seconds();
mgui_scrollview_update_mouse_scroll(self, frame_time);
mgl_vec2i child_size;
if(self->child)
child_size = self->child->size;
else
child_size = (mgl_vec2i){ 0, 0 };
/* TODO: Fix all this margin crap, it should be invisible */
const int margin_width = self->widget.margin.top + self->widget.margin.bottom;
const int margin_height = self->widget.margin.top + self->widget.margin.bottom;
/* TODO: Fix all this margin crap, it should be invisible */
const int height = self->widget.size.y - margin_height;
const double scrollbar_height_ratio = child_size.y == 0 ? 0.0 : (double)height / (double)child_size.y;
const int scrollbar_height = scrollbar_height_ratio * height;
mgui_scrollview_handle_scrollbar_move(self, window, scrollbar_height_ratio);
mgui_scrollview_limit_scroll_to_child_size(self, child_size);
mgui_scrollview_draw_child(self, window, margin_width, margin_height, height, scrollbar_height, child_size);
}
|
