New example and small changes.

examples/README.md

@@ -35,6 +35,10 @@ This example shows how to create an animated character that follows the mouse.
 
 This example shows how to use the timer structure of Parin.
 
+## [Viewport](viewport.d)
+
+This example shows how to use the viewport structure of Parin.
+
 ## [Scene](scene.d)
 
 This example shows how to use the scene manager of Parin.

examples/follower.d

@@ -19,7 +19,6 @@ void ready() {
 bool update(float dt) {
     // The sprite should be updated every frame, regardless of whether it is running.
     sprite.update(dt);
-
     // Get some basic info about the mouse.
     auto mouseDistance = sprite.position.distanceTo(mouseScreenPosition);
     auto mouseDirection = sprite.position.directionTo(mouseScreenPosition);

examples/timer.d

@@ -15,10 +15,7 @@ bool update(float dt) {
     // The timer should be updated every frame, regardless of whether it is running.
     timer.update(dt);
     // Check if the timer has stopped and add 1 to the counter.
-    if (timer.hasStopped) {
-        counter += 1;
-    }
-
+    if (timer.hasStopped) counter += 1;
     drawDebugText("Counter: {}".format(counter), Vec2(8));
     drawDebugText("\nTimer: {}".format(timer.time), Vec2(8));
     return false;

examples/viewport.d

@@ -0,0 +1,27 @@
+/// This example shows how to use the viewport structure of Parin.
+import parin;
+
+// The game variables.
+auto viewport = Viewport(black);
+
+void ready() {
+    // Resize the viewport based on the current resolution.
+    viewport.resize(resolutionWidth / 2, resolutionHeight / 2);
+}
+
+bool update(float dt) {
+    // Resize the viewport when the window is resized.
+    if (isWindowResized) viewport.resize(resolutionWidth / 2, resolutionHeight / 2);
+    // Draw the mouse position inside the viewport.
+    viewport.attach();
+    drawVec2(mouseScreenPosition - Rect(resolution * Vec2(0.5), viewport.size).centerArea.position, 24);
+    viewport.detach();
+    // Draw the viewport and other things inside the window.
+    drawViewport(viewport, resolution * Vec2(0.5), DrawOptions(Hook.center));
+    drawDebugText("Move the mouse inside the black box.", Vec2(8), DrawOptions(Vec2(2)));
+    return false;
+}
+
+void finish() { }
+
+mixin runGame!(ready, update, finish);

source/parin/engine.d

@@ -555,17 +555,16 @@ struct SoundId {
 /// Represents the viewing area for rendering.
 struct Viewport {
     rl.RenderTexture2D data;
-    Color color = gray;
+    Color color;
     Blend blend;
     bool isAttached;
 
     @safe @nogc nothrow:
 
     /// Initializes the viewport with the given size, background color and blend mode.
-    this(int width, int height, Color color = gray, Blend blend = Blend.alpha) {
+    this(Color color, Blend blend = Blend.alpha) {
         this.color = color;
         this.blend = blend;
-        resize(width, height);
     }
 
     /// Checks if the viewport is not loaded.
@@ -1956,12 +1955,7 @@ void drawLine(Line area, float size, Color color = white) {
 /// Draws a portion of the specified texture at the given position with the specified draw options.
 @trusted
 void drawTextureArea(Texture texture, Rect area, Vec2 position, DrawOptions options = DrawOptions()) {
-    if (texture.isEmpty) {
-        return;
-    } else if (area.size.x <= 0.0f || area.size.y <= 0.0f) {
-        return;
-    }
-
+    if (texture.isEmpty || area.size.x <= 0.0f || area.size.y <= 0.0f) return;
     auto target = Rect(position, area.size * options.scale.abs());
     auto flip = options.flip;
     if (options.scale.x < 0.0f && options.scale.y < 0.0f) {
@@ -2035,10 +2029,7 @@ void drawViewport(Viewport viewport, Vec2 position, DrawOptions options = DrawOp
 /// Draws a single character from the specified font at the given position with the specified draw options.
 @trusted
 void drawRune(Font font, dchar rune, Vec2 position, DrawOptions options = DrawOptions()) {
-    if (font.isEmpty) {
-        return;
-    }
-
+    if (font.isEmpty) return;
     auto rect = toParin(rl.GetGlyphAtlasRec(font.data, rune));
     auto origin = options.origin == Vec2() ? rect.origin(options.hook) : options.origin;
     rl.rlPushMatrix();
@@ -2066,10 +2057,7 @@ void drawRune(FontId font, dchar rune, Vec2 position, DrawOptions options = Draw
 /// Draws the specified text with the given font at the given position using the provided draw options.
 @trusted
 void drawText(Font font, IStr text, Vec2 position, DrawOptions options = DrawOptions()) {
-    if (font.isEmpty || text.length == 0) {
-        return;
-    }
-
+    if (font.isEmpty || text.length == 0) return;
     // TODO: Make it work with negative scale values.
     auto origin = Rect(measureTextSize(font, text)).origin(options.hook);
     rl.rlPushMatrix();