scrollbars

1 files changed, 158 insertions, 0 deletions

diff --git a/gui.c b/gui.c
index 0fe1f69..366e420 100644
--- a/gui.c
+++ b/gui.c
@@ -1,4 +1,5 @@
 #include "gui.h"
+#include "maths.h"
 #include "memory.h"
 #include "plat.h"
 #include "render.h"
@@ -103,14 +104,109 @@ int gui_btn(GUI* g, Rect r, const char* text) {
 void gui_scrollable(
 	GUI* g,
 	Rect r,
+	const int* cs,
 	GUI_Scroll_State* state,
 	GUI_Scrollable_Draw_Fn fn
 ) {
 	GUI_Scrollable* e = gui_alloc(g, sizeof *e);
+	Rect srx, sry;
+	int nx, ny, h = mouse_over(g->app, &r);
+	int size = 15;
 	e->el.type = gui_el_type_scrollable;
 	e->el.r = r;
+	e->cs[0] = cs[0];
+	e->cs[1] = cs[1];
 	e->ss = state;
 	e->draw = fn;
+	e->vp[0] = r.w - 2;
+	e->vp[1] = r.h - 2;
+	if ((nx = cs[0] - r.w) > 0) {
+		srx.h = size;
+		srx.w = r.w;
+		srx.x = r.x;
+		srx.y = r.y + r.h - srx.h;
+		e->vp[1] -= srx.h;
+		if (h)
+			state->x -= g->app->scrollx;
+	}
+	if ((ny = cs[1] - r.h) > 0) {
+		sry.w = size;
+		sry.h = r.h;
+		sry.x = r.x + r.w - sry.w;
+		sry.y = r.y;
+		e->vp[0] -= sry.w;
+		if (h)
+			state->y -= g->app->scrolly;
+	}
+	if (nx > 0 && ny > 0) {
+		srx.w -= size;
+		sry.h -= size;
+		nx = cs[0] - (r.w - size);
+		ny = cs[1] - (r.h - size);
+	}
+	if (nx > 0) {
+		state->x = clamp(state->x, 0, nx);
+		gui_scrollbar(g, state, srx, nx, 1);
+	}
+	if (ny > 0) {
+		state->y = clamp(state->y, 0, ny);
+		gui_scrollbar(g, state, sry, ny, 0);
+	}
+}
+
+void gui_scrollbar(
+	GUI* g,
+	GUI_Scroll_State* state,
+	Rect r,
+	int diff,
+	int horizontal
+) {
+	GUI_Scrollbar* e = gui_alloc(g, sizeof *e);
+	int ls = g->app->mbtn_states[mbtn_left];
+	int mh = 30;
+	e->el.type = gui_el_type_scrollbar;
+	e->el.r = r;
+	if (horizontal) {
+		e->handle.x = r.x + state->x * (r.w - e->handle.w) / diff;
+		e->handle.y = r.y;
+		e->handle.w = r.w * r.w / (r.w + diff);
+		e->handle.w = maxi(e->handle.w, mh);
+		e->handle.h = r.h;
+	} else {
+		e->handle.x = r.x;
+		e->handle.y = r.y + state->y * (r.h - e->handle.h) / diff;
+		e->handle.w = r.w;
+		e->handle.h = r.h * r.h / (r.h + diff);
+		e->handle.h = maxi(e->handle.h, mh);
+	}
+	e->s = state;
+	e->h = horizontal;
+	e->hover = 0;
+	e->active = 0;
+	if (
+		mouse_over(g->app, &e->handle) &&
+		ls & key_state_just_pressed
+	) {
+		state->grabbed[horizontal] = 1;
+		state->graboff[horizontal] =
+			(e->handle.x - g->app->mx);
+	}
+#define doscroll(a, ad) \
+		int scroll = state->a + g->app->dm ## a; \
+		scroll = clamp(scroll, 0, diff); \
+		state->a = scroll; \
+		e->handle.a = scroll * (r.ad - e->handle.ad) / diff + r.a;
+	if (state->grabbed[horizontal]) {
+		if (horizontal) {
+			doscroll(x, w)
+		} else {
+			doscroll(y, h)
+		}
+		if (ls & key_state_just_released)
+			state->grabbed[horizontal] = 0;
+		if (ls & key_state_just_released)
+			state->grabbed[horizontal] = 0;
+	}
 }
 
 void rect_cfit(Rect* r) {
@@ -177,11 +273,70 @@ void draw_scrollable(
 	Rect rect = s->el.r;
 	draw_container(r, &s->el.r, 0);
 	rect_cfit(&rect);
+	rect.w = s->vp[0];
+	rect.h = s->vp[1];
 	ren_clip(r, &rect);
 	s->draw(g, r, &rect, s->ss);
 	ren_clipr(r);
 }
 
+void draw_scrollbar(
+	GUI* g,
+	Renderer* r,
+	const GUI_Scrollbar* s
+) {
+	int a = s->s->grabbed[s->h];
+	Colour out1       = make_colour(0xffffff, 0xff);
+	Colour out2       = make_colour(0x000000, 0xff);
+	Rect rect, h = s->handle;
+	(void)g;
+	if (a) {
+		Colour t = out1;
+		out1 = out2;
+		out2 = t;
+	}
+	draw_container(r, &s->el.r, 0);
+	if (s->h) {
+		int i;
+		h.x++;
+		h.w -= 2;
+		rect.w = 1;
+		rect.h = 7;
+		rect.x = s->handle.x + s->handle.w / 2 - 7;
+		rect.y = s->handle.y + s->handle.h / 2 - rect.h / 2;
+		if (a) {
+			rect.x++;
+			rect.y++;
+		}
+		draw_container(r, &h, a);
+		for (i = 0; i < 3; i++) {
+			ren_rect(r, out1, &rect);
+			rect.x++;
+			ren_rect(r, out2, &rect);
+			rect.x += 4;
+		}
+	} else {
+		int i;
+		h.y++;
+		h.h -= 2;
+		rect.w = 7;
+		rect.h = 1;
+		rect.x = s->handle.x + s->handle.w / 2 - rect.w / 2;
+		rect.y = s->handle.y + s->handle.h / 2 - 7;
+		if (a) {
+			rect.x++;
+			rect.y++;
+		}
+		draw_container(r, &h, a);
+		for (i = 0; i < 3; i++) {
+			ren_rect(r, out1, &rect);
+			rect.y++;
+			ren_rect(r, out2, &rect);
+			rect.y += 4;
+		}
+	}
+}
+
 void gui_end(GUI* g, Renderer* r) {
 	GUI_El* el = g->first;
 	while (el) {
@@ -192,6 +347,9 @@ void gui_end(GUI* g, Renderer* r) {
 			case gui_el_type_scrollable:
 				draw_scrollable(g, r, (GUI_Scrollable*)el);
 				break;
+			case gui_el_type_scrollbar:
+				draw_scrollbar(g, r, (GUI_Scrollbar*)el);
+				break;
 		}
 		el = el->next;
 	}