From ff7267d04424c9d438e2e1814a6dfc8dddee9cff Mon Sep 17 00:00:00 2001
From: FunkyFr3sh <cc.red.alert.1@googlemail.com>
Date: Tue, 3 Jul 2018 20:54:05 +0200
Subject: [PATCH] try to use a single memcpy if possible - adds stretching
 support (not used in C&C games though)

---
 ddraw.rc      |  2 +-
 src/surface.c | 66 ++++++++++++++++++++++++++++++++++-----------------
 2 files changed, 45 insertions(+), 23 deletions(-)

diff --git a/ddraw.rc b/ddraw.rc
index f2c85fb..e09f1eb 100644
--- a/ddraw.rc
+++ b/ddraw.rc
@@ -2,7 +2,7 @@
 #define vxstr(a,b,c,d) str(a##.##b##.##c##.##d)
 #define str(s) #s
 
-#define VERSION 1,1,7,3
+#define VERSION 1,1,7,4
 
 1 VERSIONINFO
 FILEVERSION VERSION
diff --git a/src/surface.c b/src/surface.c
index 2a65289..2600fbb 100644
--- a/src/surface.c
+++ b/src/surface.c
@@ -104,29 +104,51 @@ HRESULT __stdcall ddraw_surface_Blt(IDirectDrawSurfaceImpl *This, LPRECT lpDestR
 
     if(Source)
     {
-        int dx=0,dy=0; 
-        if (lpDestRect)
-        {
-            dx=lpDestRect->left;
-            dy=lpDestRect->top; 
-        }
-        int x0=0,y0=0,x1=Source->width,y1=Source->height; 
-        if (lpSrcRect)
-        { 
-            x0 = max(x0, lpSrcRect->left); 
-            x1 = min(x1, lpSrcRect->right); 
-            y0 = max(y0, lpSrcRect->top); 
-            y1 = min(y1, lpSrcRect->bottom); 
-        } 
-        unsigned char* to = (unsigned char *)This->surface + dy*This->width + dx; 
-        unsigned char* from = (unsigned char *)Source->surface + y0*Source->width + x0;
-        int s = x1-x0; 
+        //BitBlt(This->hDC, lpDestRect->left, lpDestRect->top, lpDestRect->right, lpDestRect->bottom,
+        //    Source->hDC, lpSrcRect->left, lpSrcRect->top, SRCCOPY);
+
+        int dst_w = lpDestRect->right - lpDestRect->left;
+        int dst_h = lpDestRect->bottom - lpDestRect->top;
+        int src_w = lpSrcRect->right - lpSrcRect->left;
+        int src_h = lpSrcRect->bottom - lpSrcRect->top;
+
+        if (dst_w != src_w || dst_h != src_h)
+        {
+            StretchBlt(This->hDC, lpDestRect->left, lpDestRect->top, lpDestRect->right, lpDestRect->bottom,
+                Source->hDC, lpSrcRect->left, lpSrcRect->top, lpSrcRect->right, lpSrcRect->bottom, SRCCOPY);
+        }
+        else if (dst_w == This->width && dst_h == This->height &&
+                 src_w == Source->width && src_h == Source->height)
+        {
+            memcpy(This->surface, Source->surface, This->width * This->height * This->lXPitch);
+        }
+        else
+        {
+            int dx=0,dy=0;
+            if (lpDestRect)
+            {
+                dx=lpDestRect->left;
+                dy=lpDestRect->top;
+            }
+            int x0=0,y0=0,x1=Source->width,y1=Source->height;
+            if (lpSrcRect)
+            {
+                x0 = max(x0, lpSrcRect->left);
+                x1 = min(x1, lpSrcRect->right);
+                y0 = max(y0, lpSrcRect->top);
+                y1 = min(y1, lpSrcRect->bottom);
+            }
+            unsigned char* to = (unsigned char *)This->surface + dy*This->width + dx;
+            unsigned char* from = (unsigned char *)Source->surface + y0*Source->width + x0;
+            int s = x1-x0;
+
+            int y;
+            for(y=y0; y<y1; ++y, to+=This->width, from+=Source->width)
+            {
+                memcpy(to, from, s);
+            }
+        }
 
-        int y;
-        for(y=y0; y<y1; ++y, to+=This->width, from+=Source->width)
-        { 
-            memcpy(to, from, s); 
-        } 
     }
 
     if(This->caps & DDSCAPS_PRIMARYSURFACE && !(This->flags & DDSD_BACKBUFFERCOUNT) && ddraw->render.run)