ddraw: Return early in d3d_device7_DrawPrimitive() with a 0 vertex count.

dlls/ddraw/device.c

@@ -3508,8 +3508,11 @@ static HRESULT d3d_device7_DrawPrimitive(IDirect3DDevice7 *iface,
     TRACE("iface %p, primitive_type %#x, fvf %#x, vertices %p, vertex_count %u, flags %#x.\n",
             iface, primitive_type, fvf, vertices, vertex_count, flags);
 
-    if (!vertices)
-        return DDERR_INVALIDPARAMS;
+    if (!vertex_count)
+    {
+        WARN("0 vertex count.\n");
+        return D3D_OK;
+    }
 
     /* Get the stride */
     stride = get_flexible_vertex_size(fvf);

dlls/ddraw/tests/ddraw2.c

@@ -10134,7 +10134,7 @@ static void test_draw_primitive(void)
     hr = IDirect3DDevice2_DrawIndexedPrimitive(device, D3DPT_TRIANGLESTRIP, D3DFVF_XYZ, NULL, 0, NULL, 0, 0);
     ok(SUCCEEDED(hr), "Failed to draw, hr %#x.\n", hr);
     hr = IDirect3DDevice2_DrawPrimitive(device, D3DPT_TRIANGLESTRIP, D3DFVF_XYZ, NULL, 0, 0);
-    todo_wine ok(SUCCEEDED(hr), "Failed to draw, hr %#x.\n", hr);
+    ok(SUCCEEDED(hr), "Failed to draw, hr %#x.\n", hr);
 
     hr = IDirect3DDevice2_DrawIndexedPrimitive(device, D3DPT_TRIANGLESTRIP, D3DFVF_XYZ, NULL, 0, indices, 4, 0);
     ok(SUCCEEDED(hr), "Failed to draw, hr %#x.\n", hr);

dlls/ddraw/tests/ddraw4.c

@@ -11427,7 +11427,7 @@ static void test_draw_primitive(void)
     hr = IDirect3DDevice3_DrawIndexedPrimitiveVB(device, D3DPT_TRIANGLESTRIP, vb, NULL, 0, 0);
     todo_wine ok(SUCCEEDED(hr), "Failed to draw, hr %#x.\n", hr);
     hr = IDirect3DDevice3_DrawPrimitive(device, D3DPT_TRIANGLESTRIP, D3DFVF_XYZ, NULL, 0, 0);
-    todo_wine ok(SUCCEEDED(hr), "Failed to draw, hr %#x.\n", hr);
+    ok(SUCCEEDED(hr), "Failed to draw, hr %#x.\n", hr);
     hr = IDirect3DDevice3_DrawPrimitiveStrided(device, D3DPT_TRIANGLESTRIP, D3DFVF_XYZ, &strided, 0, 0);
     ok(SUCCEEDED(hr), "Failed to draw, hr %#x.\n", hr);
     hr = IDirect3DDevice3_DrawPrimitiveVB(device, D3DPT_TRIANGLESTRIP, vb, 0, 0, 0);

dlls/ddraw/tests/ddraw7.c

@@ -11694,7 +11694,7 @@ static void test_draw_primitive(void)
     hr = IDirect3DDevice7_DrawIndexedPrimitiveVB(device, D3DPT_TRIANGLESTRIP, vb, 0, 0, NULL, 0, 0);
     todo_wine ok(SUCCEEDED(hr), "Failed to draw, hr %#x.\n", hr);
     hr = IDirect3DDevice7_DrawPrimitive(device, D3DPT_TRIANGLESTRIP, D3DFVF_XYZ, NULL, 0, 0);
-    todo_wine ok(SUCCEEDED(hr), "Failed to draw, hr %#x.\n", hr);
+    ok(SUCCEEDED(hr), "Failed to draw, hr %#x.\n", hr);
     hr = IDirect3DDevice7_DrawPrimitiveStrided(device, D3DPT_TRIANGLESTRIP, D3DFVF_XYZ, &strided, 0, 0);
     ok(SUCCEEDED(hr), "Failed to draw, hr %#x.\n", hr);
     hr = IDirect3DDevice7_DrawPrimitiveVB(device, D3DPT_TRIANGLESTRIP, vb, 0, 0, 0);