examples

commit 319adf93a20711ce74b1b868952c5919e8f60f4a
parent f09b54a62fa959639adb1d20972e8f4a272dd383
Author: Henry Wilson <henry@henryandlizzy.uk>
Date:   Fri, 28 Jun 2024 21:43:08 +0100

sdl-gl: Clickable UI

Diffstat:
M
src/sdl-gl.cpp
 | 
64
++++++++++++++++++++++++++++++++++++++++++++++++++++++++--------

1 file changed, 56 insertions(+), 8 deletions(-)
diff --git a/src/sdl-gl.cpp b/src/sdl-gl.cpp
@@ -135,6 +135,11 @@ struct rgb
 		return {r + rhs.r, g + rhs.g, b + rhs.b};
 	}
 
+	rgb& operator *=(float rhs) { r *= rhs; g *= rhs; b *= rhs; return *this; }
+	rgb& operator /=(float rhs) { r /= rhs; g /= rhs; b /= rhs; return *this; }
+	rgb operator *(float rhs) const { return rgb{*this} *= rhs; }
+	rgb operator /(float rhs) const { return rgb{*this} /= rhs; }
+
 	static rgb random()
 	{
 		return {dis(gen), dis(gen), dis(gen)};
@@ -196,6 +201,7 @@ struct circle
 
 point pan = {0, 0};
 
+screen_coord mouse_coord;
 point mouse_pos;
 
 struct shp
@@ -260,9 +266,18 @@ void presentScene(void)
 struct panel
 {
 	screen_coord pos, size;
+	rgb colour;
 	void draw() const;
+	bool colliding(screen_coord c)
+	{
+		auto br = pos + size;
+		return c.x >= pos.x && c.y >= pos.y && c.x < br.x && c.y < br.y;
+	}
 };
 
+panel menu;
+bool details;
+
 void panel::draw() const
 {
 	auto tl = window_to_gl(pos);
@@ -271,7 +286,7 @@ void panel::draw() const
 	auto br = window_to_gl(pos + size);
 
 	glBegin(GL_TRIANGLE_STRIP);
-	glColor3d(.5, .5, .5);
+	glColor(colour);
 	glVertex(tl);
 	glVertex(tr);
 	glVertex(bl);
@@ -289,14 +304,14 @@ void panel::draw() const
 	bl.x += half.x;
 
 	glBegin(GL_LINE_STRIP);
-	glColor3d(.25, .25, .25);
+	glColor(colour / 2.f);
 	glVertex(bl);
 	glVertex(br);
 	glVertex(tr);
 	glEnd();
 
 	glBegin(GL_LINE_STRIP);
-	glColor3d(.7, .7, .7);
+	glColor(colour * 1.5f);
 	glVertex(bl);
 	glVertex(tl);
 	glVertex(tr);
@@ -380,7 +395,8 @@ void key(SDL_KeyboardEvent& e)
 
 void mouse_motion(SDL_MouseMotionEvent& e)
 {
-	mouse_pos = window_to_local({e.x, e.y}) - pan;
+	mouse_coord = {e.x, e.y};
+	mouse_pos = window_to_local(mouse_coord) - pan;
 }
 
 awaitable_value<SDL_MouseButtonEvent const> click_event;
@@ -392,6 +408,12 @@ coroutine_task mouse_task()
 	{
 		SDL_MouseButtonEvent const& e = co_await click_event;
 		point drag_pos = pan - window_to_local({e.x, e.y});
+		if (menu.colliding(mouse_coord))
+		{
+			if (e.button == SDL_BUTTON_LEFT)
+				details = !details;
+			continue;
+		}
 		switch (e.button)
 		{
 		case SDL_BUTTON_RIGHT:
@@ -522,7 +544,7 @@ void init_shape()
 			shape.wireframe.push_back(i);
 	}
 	{
-		constexpr int n = 20;
+		constexpr int n = 64;
 		shapes.emplace_back();
 		auto& shape = shapes.back();
 		shape.mode = GL_TRIANGLE_STRIP;
@@ -646,11 +668,15 @@ font* fnt;
 void draw_UI()
 {
 	std::vector<std::string> strings;
+	strings.push_back(std::format("scale: {:.2}", scale));
+	strings.push_back(std::format("  pan: ({:.1}, {:.1})", pan.x, pan.y));
 	strings.push_back(std::format("{} shapes", shapes.size()));
 	strings.push_back(std::format("{} objects", objs.size()));
-	size_t width = 2 + fnt->hdr.width * std::ranges::max(strings | std::views::transform([](auto const& s){ return s.size(); }));
-	size_t height = 2 + fnt->hdr.height * strings.size();
-	panel{0, 0, (int)width, (int)height}.draw();
+	int width = (int)(2 + fnt->hdr.width * std::ranges::max(strings | std::views::transform([](auto const& s){ return s.size(); })));
+	int height = (int)(2 + fnt->hdr.height * strings.size());
+	menu.size = {width, height};
+	menu.colour = menu.colliding(mouse_coord) ? rgb{.6, .6, .6} : rgb{.4, .4, .4};
+	menu.draw();
 	glColor3f(0, 0, 0);
 	int y = 1;
 	for (auto const& s : strings)
@@ -658,6 +684,28 @@ void draw_UI()
 		fnt->draw(s, {1, y});
 		y += fnt->hdr.height;
 	}
+
+	if (not details)
+		return;
+
+	auto x = (int)width;
+	strings.clear();
+	for (auto const& [i, o] : objs | deref | std::views::enumerate)
+		strings.push_back(std::format("{}: size {}", i, o.pos.radius));
+
+	if (strings.empty())
+		return;
+
+	width = (int)(2 + fnt->hdr.width * std::ranges::max(strings | std::views::transform([](auto const& s){ return s.size(); })));
+	height = (int)(2 + fnt->hdr.height * strings.size());
+	panel{{x, 0}, {width, height}, rgb{.4, .4, .4}}.draw();
+	glColor3f(0, 0, 0);
+	y = 1;
+	for (auto const& s : strings)
+	{
+		fnt->draw(s, {x + 1, y});
+		y += fnt->hdr.height;
+	}
 }
 
 int main()