Implemented RenderHandler class with zoom. This zoom is pretty garbage but on the right track I think.

2026-07-30 22:55:03 -07:00 · 2025-03-18 09:37:01 -07:00
parent 529522499e
commit 0ba801ccff
4 changed files with 162 additions and 56 deletions
@@ -0,0 +1,96 @@
+using System;
+using Microsoft.Xna.Framework;
+using Microsoft.Xna.Framework.Graphics;
+
+namespace LunaLightXMG
+{
+    public class RenderHandler
+    {
+        // fields 
+        private GraphicsDevice graphicsDevice;
+        private SpriteBatch spriteBatch;
+        private RenderTarget2D renderTarget;
+        private Rectangle renderDestination;
+
+        private int retroWidth;
+        private int retroHeight;
+        private float zoomLevel = 1.0f;
+        private float zoomTarget = 1.0f;
+        private readonly float zoomMin = 0.75f;
+        private readonly float zoomNorm = 1.0f;
+        private readonly float zoomMax = 1.25f;
+        private readonly float zoomSpeed = 0.1f;
+        public float ZoomLevel {get => zoomLevel;}
+        
+        // constructor
+        public RenderHandler(GraphicsDevice graphicsDevice, SpriteBatch spriteBatch, int retroWidth, int retroHeight)
+        {
+            this.graphicsDevice = graphicsDevice;
+            this.spriteBatch = spriteBatch;
+            this.retroWidth = retroWidth;
+            this.retroHeight = retroHeight;
+            
+            renderTarget = new RenderTarget2D(graphicsDevice, retroWidth, retroHeight);
+
+            CalculateRenderDestination();
+        }
+        
+        public void ZoomIn()
+        {
+            zoomTarget = zoomMin;
+        }
+        
+        public void ZoomNormalize()
+        {
+            zoomTarget = zoomNorm;
+        }
+
+        public void ZoomOut()
+        {
+            zoomTarget = zoomMax;
+        }
+
+        public void UpdateZoom()
+        {
+            zoomLevel = MathHelper.Lerp(zoomLevel, zoomTarget, zoomSpeed);
+            zoomLevel = MathHelper.Clamp(zoomLevel, zoomMin, zoomMax);
+            CalculateRenderDestination();
+        }
+
+        public void CalculateRenderDestination()
+        {
+            Point screenSize = graphicsDevice.Viewport.Bounds.Size;
+            // Calculate the integer scale factor
+            int scaleX = screenSize.X / (int)(retroWidth * zoomLevel);
+            int scaleY = screenSize.Y / (int)(retroHeight * zoomLevel);
+
+            // Set renderDestination 
+            renderDestination.Width = retroWidth * scaleX;
+            renderDestination.Height = retroHeight * scaleY;
+            renderDestination.X = (screenSize.X - renderDestination.Width) / 2;
+            renderDestination.Y = (screenSize.Y - renderDestination.Height) / 2;
+        }
+    
+        public void BeginRenderTarget(Matrix cameraMatrix)
+        {
+            graphicsDevice.SetRenderTarget(renderTarget);
+            graphicsDevice.Clear(Color.Black);
+
+            spriteBatch.Begin(transformMatrix: cameraMatrix, samplerState: SamplerState.PointClamp);
+        }
+        
+        public void EndRenderTarget()
+        {
+            spriteBatch.End();
+            graphicsDevice.SetRenderTarget(null);
+        }
+
+        public void DrawRenderTarget()
+        {
+            spriteBatch.Begin(samplerState: SamplerState.PointClamp);
+            spriteBatch.Draw(renderTarget, renderDestination, Color.White);
+            spriteBatch.End();
+        }
+
+    }
+}