colourpicker

Commit: 4c2545a25a1029b986dc7165db81ddff0ec516aa
Parent: 8e4d0f1457ef72ba9568d858e8c0ea65fefb2d08
Author: Randy Palamar
Date:   Sat,  8 Jun 2024 11:35:30 -0600

draw modifiable sliders

Diffstat:
M
colourpicker.c
 | 
152
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--------
M
main.c
 | 
9
++++++++-
M
util.c
 | 
25
+++++++++++++++++++++++++

3 files changed, 170 insertions(+), 16 deletions(-)
diff --git a/colourpicker.c b/colourpicker.c
@@ -2,6 +2,124 @@
 #include <raylib.h>
 #include "util.c"
 
+static v2
+center_text_in_rect(Rect r, const char *text, Font font, f32 fontsize)
+{
+	v2 ts    = { .rv = MeasureTextEx(font, text, fontsize, 0) };
+	v2 delta = { .w = r.size.w - ts.w, .h = r.size.h - ts.h };
+	return (v2) {
+		.x = r.pos.x + 0.5 * delta.w,
+		.y = r.pos.y + 0.5 * delta.h,
+	};
+}
+
+static Rect
+cut_rect_middle(Rect r, f32 left, f32 right)
+{
+	ASSERT(left <= right);
+	r.pos.x  += r.size.w * left;
+	r.size.w  = r.size.w * (right - left);
+	return r;
+}
+
+static Rect
+cut_rect_left(Rect r, f32 fraction)
+{
+	r.size.w *= fraction;
+	return r;
+}
+
+static Rect
+cut_rect_right(Rect r, f32 fraction)
+{
+	r.pos.x  += fraction * r.size.w;
+	r.size.w *= (1 - fraction);
+	return r;
+}
+
+static f32
+do_slider(Rect r, char *label, f32 current, Font font)
+{
+	Rect lr = cut_rect_left(r, 0.1);
+	Rect vr = cut_rect_right(r, 0.85);
+
+	Rect sr = cut_rect_middle(r, 0.1, 0.85);
+	sr.size.h *= 0.75;
+	sr.pos.y  += r.size.h * 0.125;
+
+	v2 fpos = center_text_in_rect(lr, label, font, 48);
+	DrawTextEx(font, label, fpos.rv, 48, 0, LIGHTGRAY);
+
+	v2 mouse = { .rv = GetMousePosition() };
+	if (CheckCollisionPointRec(mouse.rv, sr.rr)) {
+		f32 wheel = GetMouseWheelMove();
+		if (IsMouseButtonDown(MOUSE_BUTTON_LEFT))
+			current = (mouse.x - sr.pos.x) / sr.size.w;
+		current += 4 * wheel / sr.size.w;
+		CLAMP(current, 0.0, 1.0);
+	}
+
+	DrawRectangleRounded(sr.rr, 1.0, 0, PURPLE);
+	v2 start = {
+		.x = sr.pos.x + current * sr.size.w,
+		.y = sr.pos.y + sr.size.h,
+	};
+	v2 end = start;
+	end.y -= sr.size.h;
+	DrawLineEx(start.rv, end.rv, 8, BLACK);
+
+	const char *value = TextFormat("%0.02f", current);
+	fpos = center_text_in_rect(vr, value, font, 36);
+	DrawTextEx(font, value, fpos.rv, 36, 0, LIGHTGRAY);
+
+	return current;
+}
+
+static enum colour_picker_mode
+do_status_bar(Rect r, enum colour_picker_mode mode, Color colour, Font font)
+{
+	Rect hr = cut_rect_left(r, 0.5);
+	Rect sr = cut_rect_right(r, 0.7);
+
+	const char *hex = TextFormat("%02x%02x%02x%02x",
+	                             colour.r, colour.b, colour.g,
+	                             colour.a);
+	v2 fpos = center_text_in_rect(hr, hex, font, 48);
+	DrawTextEx(font, hex, fpos.rv, 48, 0, LIGHTGRAY);
+
+	v2 mouse = { .rv = GetMousePosition() };
+
+	if (CheckCollisionPointRec(mouse.rv, hr.rr)) {
+		if (IsMouseButtonDown(MOUSE_BUTTON_LEFT))
+			SetClipboardText(hex);
+	}
+
+	if (CheckCollisionPointRec(mouse.rv, sr.rr)) {
+		if (IsMouseButtonPressed(MOUSE_BUTTON_LEFT)) {
+			if (mode == HSV)
+				mode = RGB;
+			else
+				mode++;
+		}
+		if (IsMouseButtonPressed(MOUSE_BUTTON_RIGHT)) {
+			if (mode == RGB)
+				mode = HSV;
+			else
+				mode--;
+		}
+	}
+
+	char *mtext;
+	switch (mode) {
+	case RGB: mtext = "RGB"; break;
+	case HSV: mtext = "HSV"; break;
+	}
+	fpos = center_text_in_rect(sr, mtext, font, 48);
+	DrawTextEx(font, mtext, fpos.rv, 48, 0, LIGHTGRAY);
+
+	return mode;
+}
+
 void
 do_colour_picker(ColourPickerCtx *ctx)
 {
@@ -9,12 +127,12 @@ do_colour_picker(ColourPickerCtx *ctx)
 	DrawFPS(20, 20);
 
 	uv2 ws = ctx->window_size;
+	Color colour = ColorFromNormalized(ctx->colour.rv);
 
 	{
 		v2  cc = { .x = (f32)ws.w / 2, .y = (f32)ws.h / 4 };
 		DrawCircleSector(cc.rv, 0.6 * cc.x, 0, 360, 69, RED);
-		DrawCircleSector(cc.rv, 0.58 * cc.x, 0, 360, 69, BLACK);
-		DrawText("Hello World!", ws.w * 0.3, ws.h / 4, 48, BLUE);
+		DrawCircleSector(cc.rv, 0.58 * cc.x, 0, 360, 69, colour);
 	}
 
 	{
@@ -24,24 +142,28 @@ do_colour_picker(ColourPickerCtx *ctx)
 	}
 
 	{
-		v2 subregion    = {
-			.x = (f32)ws.w * 0.9,
-			.y = (f32)ws.h / 2 * 0.9,
+		Rect subregion = {
+			.pos  = { .x = 0.05 * (f32)ws.w, .y = (f32)ws.h / 2, },
+			.size = { .w = (f32)ws.w * 0.9, .h = (f32)ws.h / 2 * 0.9 },
 		};
 
-		v2 starting_pos = {
-			.x = 0.05 * (f32)ws.w,
-			.y = (f32)ws.h / 2 + 0.25 * ((f32)ws.h / 2),
-		};
+		Rect sb = subregion;
+		sb.size.h *= 0.25;
+		ctx->mode  = do_status_bar(sb, ctx->mode, colour, ctx->font);
+
+		Rect r    = subregion;
+		r.pos.y  += 0.25 * ((f32)ws.h / 2);
+		r.size.h *= 0.15;
 
-		v2 size = { .x = subregion.x, .y = 0.15 * subregion.y };
+		ctx->colour.r = do_slider(r, "R:", ctx->colour.r, ctx->font);
 
-		DrawRectangleV(starting_pos.rv, size.rv, DARKGREEN);
+		r.pos.y += r.size.h + 0.03 * ((f32)ws.h / 2);
+		ctx->colour.g = do_slider(r, "G:", ctx->colour.g, ctx->font);
 
-		starting_pos.y += size.y + 0.1 * ((f32)ws.h / 2);
-		DrawRectangleV(starting_pos.rv, size.rv, DARKGREEN);
+		r.pos.y += r.size.h + 0.03 * ((f32)ws.h / 2);
+		ctx->colour.b = do_slider(r, "B:", ctx->colour.b, ctx->font);
 
-		starting_pos.y += size.y + 0.1 * ((f32)ws.h / 2);
-		DrawRectangleV(starting_pos.rv, size.rv, DARKGREEN);
+		r.pos.y += r.size.h + 0.03 * ((f32)ws.h / 2);
+		ctx->colour.a = do_slider(r, "A:", ctx->colour.a, ctx->font);
 	}
 }
diff --git a/main.c b/main.c
@@ -2,6 +2,7 @@
 #include <dlfcn.h>
 #include <fcntl.h>
 #include <raylib.h>
+#include <stdio.h>
 #include <sys/stat.h>
 
 #include "util.c"
@@ -11,6 +12,8 @@ typedef struct timespec Filetime;
 static const char *libname = "./libcolourpicker.so";
 static void *libhandle;
 
+static const char *fontpath = "/home/rnp/.local/share/fonts/Aozora Mincho Medium.ttf";
+
 typedef void (do_colour_picker_fn)(ColourPickerCtx *);
 static do_colour_picker_fn *do_colour_picker;
 
@@ -35,18 +38,22 @@ load_library(const char *lib)
 	dlclose(libhandle);
 	libhandle = dlopen(lib, RTLD_NOW|RTLD_LOCAL);
 	do_colour_picker = dlsym(libhandle, "do_colour_picker");
+	if (!libhandle || !do_colour_picker)
+		fprintf(stderr, "Couldn't Hot Reload ColourPicker\n");
 }
 
 int
 main(void)
 {
-	ColourPickerCtx ctx;
+	ColourPickerCtx ctx = {0};
 	ctx.window_size = (uv2){.w = 720, .h = 960};
 
 	SetConfigFlags(FLAG_VSYNC_HINT);
 	InitWindow(ctx.window_size.w, ctx.window_size.h, "Colour Picker");
 	load_library(libname);
 
+	ctx.font = LoadFontEx(fontpath, 128, 0, 0);
+
 	Filetime updated_time = get_filetime(libname);
 	while(!WindowShouldClose()) {
 		BeginDrawing();
diff --git a/util.c b/util.c
@@ -2,6 +2,8 @@
 #include <stddef.h>
 #include <stdint.h>
 
+#define ASSERT(c) do { if (!(c)) __builtin_debugtrap(); } while (0);
+
 typedef int32_t   i32;
 typedef uint32_t  u32;
 typedef float     f32;
@@ -16,10 +18,33 @@ typedef union {
 
 typedef union {
 	struct { f32 x, y; };
+	struct { f32 w, h; };
 	Vector2 rv;
 	f32 E[2];
 } v2;
 
+typedef union {
+	struct { f32 x, y, z, w; };
+	struct { f32 r, g, b, a; };
+	Vector4 rv;
+	f32 E[4];
+} v4;
+
+typedef union {
+	struct { v2 pos, size; };
+	Rectangle rr;
+} Rect;
+
+enum colour_picker_mode {
+	RGB,
+	HSV,
+};
+
 typedef struct {
 	uv2 window_size;
+	Font font;
+	v4 colour;
+	enum colour_picker_mode mode;
 } ColourPickerCtx;
+
+#define CLAMP(x, a, b) ((x) = (x) < (a) ? (a) : (x) > (b) ? (b) : (x))