Complete native numbered-save round trips

2026-07-24 23:25:54 -04:00
parent 4db7e412bd
commit 0a4e200876
17 changed files with 907 additions and 89 deletions
--- a/engine/Age.Engine/Sys4/RetainedSurfaceRasterizer.cs
+++ b/engine/Age.Engine/Sys4/RetainedSurfaceRasterizer.cs
@@ -0,0 +1,65 @@
+using Age.Engine.Model;
+
+namespace Age.Engine.Sys4;
+
+/// <summary>Platform-neutral software publication of retained gfx objects into an AGE surface.
+/// Native scripts use the same object list for the backbuffer and selected offscreen render targets.</summary>
+public static class RetainedSurfaceRasterizer
+{
+    public static int CompositeRange(
+        RgbaImage destination,
+        IReadOnlyList<RenderObject> visible,
+        long firstHandle,
+        long count,
+        Func<RenderObject, RgbaImage?> resolveSource)
+    {
+        ArgumentNullException.ThrowIfNull(destination);
+        ArgumentNullException.ThrowIfNull(visible);
+        ArgumentNullException.ThrowIfNull(resolveSource);
+        if (destination.Width <= 0 || destination.Height <= 0
+            || destination.Pixels.Length != checked(destination.Width * destination.Height * 4)
+            || count <= 0)
+            return 0;
+
+        int rendered = 0;
+        foreach (RenderObject item in visible)
+        {
+            if (item.Handle < firstHandle || item.Handle - firstHandle >= count) continue;
+
+            TransformState transform = item.Transform;
+            Affine2D localToDestination =
+                Transform2DMath.Build(transform, item.Rotation).FromLocalOrigin(item.DstX, item.DstY);
+            if (item.RangeTransform is { } rangeTransform)
+                localToDestination = localToDestination.Then(rangeTransform);
+
+            RgbaImage? source = resolveSource(item);
+            float opacity = item.Alpha / 255f;
+            float tintStrength = item.TintStrength / 255f;
+            if (source == null)
+            {
+                if (item.SurfaceResId != 0 || item.Blend == BlendKind.Opaque) continue;
+                int width = item.W > 0 ? item.W : 800;
+                int height = item.H > 0 ? item.H : 600;
+                float fillOpacity = item.MultiplyTint ? opacity : opacity * tintStrength;
+                SoftwareAffineRasterizer.FillRgba(
+                    destination.Pixels, destination.Width, destination.Height,
+                    width, height, localToDestination, item.Tint, fillOpacity);
+                rendered++;
+                continue;
+            }
+
+            if (item.W <= 0 || item.H <= 0 || item.SrcX < 0 || item.SrcY < 0) continue;
+            int widthToDraw = System.Math.Min(item.W, source.Width - item.SrcX);
+            int heightToDraw = System.Math.Min(item.H, source.Height - item.SrcY);
+            if (widthToDraw <= 0 || heightToDraw <= 0) continue;
+            SoftwareAffineRasterizer.BlitRgba(
+                destination.Pixels, destination.Width, destination.Height,
+                source.Pixels, source.Width, source.Height,
+                item.SrcX, item.SrcY, widthToDraw, heightToDraw,
+                localToDestination, item.Tint, tintStrength, opacity,
+                item.MultiplyTint, item.Blend);
+            rendered++;
+        }
+        return rendered;
+    }
+}