rounded rectangle drawing

★★★☆by Vlad Adrian (@demizdor)

There is no browser build of this example yet.

Is it the same as C?

Desktop:verified The Zig version renders a final frame that is byte-identical to the C example.
Browser:verified In headless Chrome, the Zig version gives a final frame byte-identical to the C example built for the web.

ZigC (original)

//! raylib [shapes] example - rounded rectangle drawing
//!
//! Zig-API translation of examples/shapes/shapes_rounded_rectangle_drawing.c (raylib 6.2).
//! Example contributed by Vlad Adrian (@demizdor) and reviewed by Ramon Santamaria (@raysan5)
//! Example licensed under an unmodified zlib/libpng license.
//! Copyright (c) 2018-2025 Vlad Adrian (@demizdor) and Ramon Santamaria (@raysan5)

const rl = @import("raylib");
const gui = @import("raygui");

pub fn main() void {
    // Initialization
    const screen_width = 800;
    const screen_height = 450;

    rl.initWindow(screen_width, screen_height, "raylib [shapes] example - rounded rectangle drawing");
    defer rl.closeWindow(); // Close window and OpenGL context

    var roundness: f32 = 0.2;
    var width: f32 = 200.0;
    var height: f32 = 100.0;
    var segments: f32 = 0.0;
    var line_thick: f32 = 1.0;

    var draw_rect = false;
    var draw_rounded_rect = true;
    var draw_rounded_lines = false;

    rl.setTargetFPS(60); // Set our game to run at 60 frames-per-second

    // Main game loop
    while (!rl.windowShouldClose()) { // Detect window close button or ESC key
        // Update
        const screen_w: f32 = @floatFromInt(rl.getScreenWidth());
        const screen_h: f32 = @floatFromInt(rl.getScreenHeight());
        const rec: rl.Rectangle = .{
            .x = (screen_w - width - 250) / 2,
            .y = (screen_h - height) / 2.0,
            .width = width,
            .height = height,
        };

        // Draw
        rl.beginDrawing();
        defer rl.endDrawing();

        rl.clearBackground(.ray_white);

        rl.drawLine(560, 0, 560, rl.getScreenHeight(), rl.fade(.light_gray, 0.6));
        rl.drawRectangle(560, 0, rl.getScreenWidth() - 500, rl.getScreenHeight(), rl.fade(.light_gray, 0.3));

        const segment_count: i32 = @intFromFloat(segments);
        if (draw_rect) rl.drawRectangleRec(rec, rl.fade(.gold, 0.6));
        if (draw_rounded_rect) rl.drawRectangleRounded(rec, roundness, segment_count, rl.fade(.maroon, 0.2));
        if (draw_rounded_lines) rl.drawRectangleRoundedLinesEx(rec, roundness, segment_count, line_thick, rl.fade(.maroon, 0.4));

        // Draw GUI controls
        _ = gui.sliderBar(.{ .x = 640, .y = 40, .width = 105, .height = 20 }, "Width", rl.textFormat("{d:.2}", .{width}), &width, 0, screen_w - 300);
        _ = gui.sliderBar(.{ .x = 640, .y = 70, .width = 105, .height = 20 }, "Height", rl.textFormat("{d:.2}", .{height}), &height, 0, screen_h - 50);
        _ = gui.sliderBar(.{ .x = 640, .y = 140, .width = 105, .height = 20 }, "Roundness", rl.textFormat("{d:.2}", .{roundness}), &roundness, 0.0, 1.0);
        _ = gui.sliderBar(.{ .x = 640, .y = 170, .width = 105, .height = 20 }, "Thickness", rl.textFormat("{d:.2}", .{line_thick}), &line_thick, 0, 20);
        _ = gui.sliderBar(.{ .x = 640, .y = 240, .width = 105, .height = 20 }, "Segments", rl.textFormat("{d:.2}", .{segments}), &segments, 0, 60);

        _ = gui.checkBox(.{ .x = 640, .y = 320, .width = 20, .height = 20 }, "DrawRoundedRect", &draw_rounded_rect);
        _ = gui.checkBox(.{ .x = 640, .y = 350, .width = 20, .height = 20 }, "DrawRoundedLines", &draw_rounded_lines);
        _ = gui.checkBox(.{ .x = 640, .y = 380, .width = 20, .height = 20 }, "DrawRect", &draw_rect);

        const manual = segments >= 4;
        rl.drawText(rl.textFormat("MODE: {s}", .{if (manual) "MANUAL" else "AUTO"}), 640, 280, 10, if (manual) .maroon else .dark_gray);

        rl.drawFPS(10, 10);
    }
}

/*******************************************************************************************
*
*   raylib [shapes] example - rounded rectangle drawing
*
*   Example complexity rating: [★★★☆] 3/4
*
*   Example originally created with raylib 2.5, last time updated with raylib 2.5
*
*   Example contributed by Vlad Adrian (@demizdor) and reviewed by Ramon Santamaria (@raysan5)
*
*   Example licensed under an unmodified zlib/libpng license, which is an OSI-certified,
*   BSD-like license that allows static linking with closed source software
*
*   Copyright (c) 2018-2025 Vlad Adrian (@demizdor) and Ramon Santamaria (@raysan5)
*
********************************************************************************************/

#include "raylib.h"

#define RAYGUI_IMPLEMENTATION
#include "raygui.h"                 // Required for GUI controls

//------------------------------------------------------------------------------------
// Program main entry point
//------------------------------------------------------------------------------------
int main(void)
{
    // Initialization
    //--------------------------------------------------------------------------------------
    const int screenWidth = 800;
    const int screenHeight = 450;

    InitWindow(screenWidth, screenHeight, "raylib [shapes] example - rounded rectangle drawing");

    float roundness = 0.2f;
    float width = 200.0f;
    float height = 100.0f;
    float segments = 0.0f;
    float lineThick = 1.0f;

    bool drawRect = false;
    bool drawRoundedRect = true;
    bool drawRoundedLines = false;

    SetTargetFPS(60);               // Set our game to run at 60 frames-per-second
    //--------------------------------------------------------------------------------------

    // Main game loop
    while (!WindowShouldClose())    // Detect window close button or ESC key
    {
        // Update
        //----------------------------------------------------------------------------------
        Rectangle rec = { ((float)GetScreenWidth() - width - 250)/2, (GetScreenHeight() - height)/2.0f, (float)width, (float)height };
        //----------------------------------------------------------------------------------

        // Draw
        //----------------------------------------------------------------------------------
        BeginDrawing();

            ClearBackground(RAYWHITE);

            DrawLine(560, 0, 560, GetScreenHeight(), Fade(LIGHTGRAY, 0.6f));
            DrawRectangle(560, 0, GetScreenWidth() - 500, GetScreenHeight(), Fade(LIGHTGRAY, 0.3f));

            if (drawRect) DrawRectangleRec(rec, Fade(GOLD, 0.6f));
            if (drawRoundedRect) DrawRectangleRounded(rec, roundness, (int)segments, Fade(MAROON, 0.2f));
            if (drawRoundedLines) DrawRectangleRoundedLinesEx(rec, roundness, (int)segments, lineThick, Fade(MAROON, 0.4f));

            // Draw GUI controls
            //------------------------------------------------------------------------------
            GuiSliderBar((Rectangle){ 640, 40, 105, 20 }, "Width", TextFormat("%.2f", width), &width, 0, (float)GetScreenWidth() - 300);
            GuiSliderBar((Rectangle){ 640, 70, 105, 20 }, "Height", TextFormat("%.2f", height), &height, 0, (float)GetScreenHeight() - 50);
            GuiSliderBar((Rectangle){ 640, 140, 105, 20 }, "Roundness", TextFormat("%.2f", roundness), &roundness, 0.0f, 1.0f);
            GuiSliderBar((Rectangle){ 640, 170, 105, 20 }, "Thickness", TextFormat("%.2f", lineThick), &lineThick, 0, 20);
            GuiSliderBar((Rectangle){ 640, 240, 105, 20}, "Segments", TextFormat("%.2f", segments), &segments, 0, 60);

            GuiCheckBox((Rectangle){ 640, 320, 20, 20 }, "DrawRoundedRect", &drawRoundedRect);
            GuiCheckBox((Rectangle){ 640, 350, 20, 20 }, "DrawRoundedLines", &drawRoundedLines);
            GuiCheckBox((Rectangle){ 640, 380, 20, 20}, "DrawRect", &drawRect);
            //------------------------------------------------------------------------------

            DrawText(TextFormat("MODE: %s", (segments >= 4)? "MANUAL" : "AUTO"), 640, 280, 10, (segments >= 4)? MAROON : DARKGRAY);

            DrawFPS(10, 10);

        EndDrawing();
        //----------------------------------------------------------------------------------
    }

    // De-Initialization
    //--------------------------------------------------------------------------------------
    CloseWindow();        // Close window and OpenGL context
    //--------------------------------------------------------------------------------------

    return 0;
}

From raylib 6.2. The original on GitHub.