examples

commit f09b54a62fa959639adb1d20972e8f4a272dd383
parent 483fbed7782d799ef4a4b04619e61b8949b4674d
Author: Henry Wilson <henry@henryandlizzy.uk>
Date:   Fri, 28 Jun 2024 00:37:07 +0100

sdl-gl: Add functional UI panel

Diffstat:
M
src/sdl-gl.cpp
 | 
52
++++++++++++++++++++++++++++++++++++++++------------

1 file changed, 40 insertions(+), 12 deletions(-)
diff --git a/src/sdl-gl.cpp b/src/sdl-gl.cpp
@@ -11,12 +11,14 @@
 #include <algorithm>
 #include <cassert>
 #include <exception>
+#include <format>
 #include <memory>
 #include <numbers>
 #include <print>
 #include <random>
 #include <ranges>
 #include <vector>
+
 #include <unistd.h>
 #include <sys/wait.h>
 #include <err.h>
@@ -176,6 +178,11 @@ point operator *(point lhs, rotor rhs)
 	return {lhs.x * rhs.s - lhs.y * rhs.xy, lhs.x * rhs.xy + lhs.y * rhs.s};
 }
 
+point& operator *=(point& lhs, rotor rhs)
+{
+	return lhs = lhs * rhs;
+}
+
 struct circle
 {
 	point pos;
@@ -264,22 +271,32 @@ void panel::draw() const
 	auto br = window_to_gl(pos + size);
 
 	glBegin(GL_TRIANGLE_STRIP);
-	glColor3d(.3, .3, .3);
+	glColor3d(.5, .5, .5);
 	glVertex(tl);
 	glVertex(tr);
 	glVertex(bl);
 	glVertex(br);
 	glEnd();
+	point half{1 / (2.f * screen.x), 1 / (2.f * screen.y)};
+
+	tl.y -= half.y;
+	tr.y -= half.y;
+	bl.y += half.y;
+	br.y += half.y;
+	tr.x -= half.x;
+	br.x -= half.x;
+	tl.x += half.x;
+	bl.x += half.x;
 
 	glBegin(GL_LINE_STRIP);
-	glColor3d(.15, .15, .15);
+	glColor3d(.25, .25, .25);
 	glVertex(bl);
 	glVertex(br);
 	glVertex(tr);
 	glEnd();
 
 	glBegin(GL_LINE_STRIP);
-	glColor3d(.5, .5, .5);
+	glColor3d(.7, .7, .7);
 	glVertex(bl);
 	glVertex(tl);
 	glVertex(tr);
@@ -512,8 +529,10 @@ void init_shape()
 		for (int i = 0; i <= n; ++i)
 		{
 			float turns = i * .5f / n;
-			float radians = turns * 2 * std::numbers::pi;
-			shape.vertices.push_back(point{0, 1 - i % 2 * .5f * sin(radians)} * rotor::angle(turns));
+			point p{0, 1};
+			p *= rotor::angle(turns);
+			p.x *= 1 - i % 2 * .45f;
+			shape.vertices.push_back(p);
 		}
 		for (int i = 0; i <= n / 2; ++i)
 			shape.wireframe.push_back(i * 2);
@@ -614,10 +633,10 @@ struct font
 
 		return br_screen;
 	}
-	screen_coord draw(char const* str, screen_coord pos)
+	screen_coord draw(std::string_view str, screen_coord pos)
 	{
-		while (*str)
-			pos.x = draw(*str++, pos).x;
+		for (auto c : str)
+			pos.x = draw(c, pos).x;
 		return pos;
 	}
 };
@@ -626,10 +645,19 @@ font* fnt;
 
 void draw_UI()
 {
-	panel{50, 50, 149, 49}.draw();
-	glColor3f(1,1,1);
-	fnt->draw("Hello, World!", {51, 51});
-	panel{50, 100, 149, 49}.draw();
+	std::vector<std::string> strings;
+	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();
+	glColor3f(0, 0, 0);
+	int y = 1;
+	for (auto const& s : strings)
+	{
+		fnt->draw(s, {1, y});
+		y += fnt->hdr.height;
+	}
 }
 
 int main()