WINTERMUTE: Avoid using Graphics::copyFrom to copy FMV-frames.

copyFrom frees and reallocates the surface for every update, as long
as the dimensions and format stay the same, we can do with just a
memcpy.

This gives a tiny improvement in the update-part of the Theora-player
(on the order of a bit more than 1 second saved total in the 1:28 long
J.U.L.I.A.-intro)

1 files changed, 8 insertions, 2 deletions

diff --git a/engines/wintermute/base/gfx/osystem/base_surface_osystem.cpp b/engines/wintermute/base/gfx/osystem/base_surface_osystem.cpp
index 9ec8573a87..73797f20f3 100644
--- a/engines/wintermute/base/gfx/osystem/base_surface_osystem.cpp
+++ b/engines/wintermute/base/gfx/osystem/base_surface_osystem.cpp
@@ -447,8 +447,14 @@ bool BaseSurfaceOSystem::drawSprite(int x, int y, Rect32 *rect, Rect32 *newRect,
 
 bool BaseSurfaceOSystem::putSurface(const Graphics::Surface &surface, bool hasAlpha) {
 	_loaded = true;
-	_surface->free();
-	_surface->copyFrom(surface);
+	if (surface.format == _surface->format && surface.w == _surface->w && surface.h == _surface->h) {
+		const byte *src = (const byte*) surface.getBasePtr(0, 0);
+		byte *dst = (byte*) _surface->getBasePtr(0, 0);
+		memcpy(dst, src, surface.pitch * surface.h);
+	} else {
+		_surface->free();
+		_surface->copyFrom(surface);
+	}
 	if (hasAlpha) {
 		_alphaType = TransparentSurface::ALPHA_FULL;
 	} else {