diff --git a/src/components/ViewerControls.tsx b/src/components/ViewerControls.tsx
index 142f3e6..b7eb4cf 100644
--- a/src/components/ViewerControls.tsx
+++ b/src/components/ViewerControls.tsx
@@ -121,6 +121,25 @@ export function ViewerControls() {
         </span>
       </Button>
 
+      {/* Camera projection toggle (Ortho ⇄ Persp) */}
+      <Button
+        variant="outline"
+        size="sm"
+        className="gap-2 h-9"
+        onClick={() => setCameraMode(cameraMode === 'ortho' ? 'persp' : 'ortho')}
+        title={cameraMode === 'ortho'
+          ? 'Vista ortogonal (CAD) — clique para perspectiva'
+          : 'Vista em perspectiva — clique para ortogonal'}
+      >
+        {cameraMode === 'ortho'
+          ? <Square className="h-3.5 w-3.5" />
+          : <Box className="h-3.5 w-3.5" />}
+        <span className="font-mono text-xs">
+          {cameraMode === 'ortho' ? 'Ortogonal' : 'Perspectiva'}
+        </span>
+      </Button>
+
+
       {/* Edges color/thickness/threshold popover */}
       {renderMode === 'edges' && (
         <Popover>