gdi32: Add a couple of SetGraphicsMode/SetWorldTransform tests, make them pass under Wine.

dlls/gdi32/dc.c

@@ -1200,10 +1200,12 @@ BOOL WINAPI GetTransform( HDC hdc, DWORD unknown, LPXFORM xform )
 BOOL WINAPI SetWorldTransform( HDC hdc, const XFORM *xform )
 {
     BOOL ret = FALSE;
-    DC *dc = get_dc_ptr( hdc );
+    DC *dc;
+
+    if (!xform) return FALSE;
 
+    dc = get_dc_ptr( hdc );
     if (!dc) return FALSE;
-    if (!xform) goto done;
 
     /* Check that graphics mode is GM_ADVANCED */
     if (dc->GraphicsMode!=GM_ADVANCED) goto done;
@@ -1211,6 +1213,9 @@ BOOL WINAPI SetWorldTransform( HDC hdc, const XFORM *xform )
     TRACE("eM11 %f eM12 %f eM21 %f eM22 %f eDx %f eDy %f\n",
         xform->eM11, xform->eM12, xform->eM21, xform->eM22, xform->eDx, xform->eDy);
 
+    /* The transform must conform to (eM11 * eM22 != eM12 * eM21) requirement */
+    if (xform->eM11 * xform->eM22 == xform->eM12 * xform->eM21) goto done;
+
     if (dc->funcs->pSetWorldTransform)
     {
         ret = dc->funcs->pSetWorldTransform(dc->physDev, xform);

dlls/gdi32/tests/mapping.c

@@ -85,6 +85,15 @@ static void test_world_transform(void)
 
     hdc = CreateCompatibleDC(0);
 
+    xform.eM11 = 1.0f;
+    xform.eM12 = 0.0f;
+    xform.eM21 = 0.0f;
+    xform.eM22 = 1.0f;
+    xform.eDx = 0.0f;
+    xform.eDy = 0.0f;
+    ret = SetWorldTransform(hdc, &xform);
+    ok(!ret, "SetWorldTransform should fail in GM_COMPATIBLE mode\n");
+
     size_cx = GetDeviceCaps(hdc, HORZSIZE);
     size_cy = GetDeviceCaps(hdc, VERTSIZE);
     res_x = GetDeviceCaps(hdc, HORZRES);
@@ -144,6 +153,16 @@ static void test_world_transform(void)
     expect_world_trasform(hdc, 1.0, 1.0);
     expect_LPtoDP(hdc, 1000, 1000);
 
+    /* The transform must conform to (eM11 * eM22 != eM12 * eM21) requirement */
+    xform.eM11 = 1.0f;
+    xform.eM12 = 2.0f;
+    xform.eM21 = 1.0f;
+    xform.eM22 = 2.0f;
+    xform.eDx = 0.0f;
+    xform.eDy = 0.0f;
+    ret = SetWorldTransform(hdc, &xform);
+    ok(!ret, "SetWorldTransform should fail with an invalid xform\n");
+
     xform.eM11 = 20.0f;
     xform.eM12 = 0.0f;
     xform.eM21 = 0.0f;
@@ -183,6 +202,16 @@ static void test_world_transform(void)
     expect_world_trasform(hdc, 20.0, 20.0);
     expect_LPtoDP(hdc, 20000, 20000);
 
+    ret = SetGraphicsMode(hdc, GM_COMPATIBLE);
+    ok(ret, "SetGraphicsMode(GM_COMPATIBLE) should not fail if DC has't an identity transform\n");
+    ret = GetGraphicsMode(hdc);
+    ok(ret == GM_COMPATIBLE, "expected GM_COMPATIBLE, got %d\n", ret);
+
+    expect_viewport_ext(hdc, 1, 1);
+    expect_window_ext(hdc, 1, 1);
+    expect_world_trasform(hdc, 20.0, 20.0);
+    expect_LPtoDP(hdc, 20000, 20000);
+
     DeleteDC(hdc);
 }