include/st: new file swrast_screen_create.h

src/gallium/include/state_tracker/swrast_screen_create.h

@@ -0,0 +1,67 @@
+#include "pipe/p_compiler.h"
+#include "util/u_debug.h"
+#include "target-helpers/wrap_screen.h"
+
+struct sw_winsys;
+
+#ifdef GALLIUM_SOFTPIPE
+#include "softpipe/sp_public.h"
+#endif
+
+#ifdef GALLIUM_LLVMPIPE
+#include "llvmpipe/lp_public.h"
+#endif
+
+#ifdef GALLIUM_CELL
+#include "cell/ppu/cell_public.h"
+#endif
+
+/*
+ * Helper function to choose and instantiate one of the software rasterizers:
+ * cell, llvmpipe, softpipe.
+ *
+ * This function could be shared, but currently causes headaches for
+ * the build systems, particularly scons if we try.  Long term, want
+ * to avoid having global #defines for things like GALLIUM_LLVMPIPE,
+ * GALLIUM_CELL, etc.  Scons already eliminates those #defines, so
+ * things that are painful for it now are likely to be painful for
+ * other build systems in the future.
+ */
+
+static INLINE struct pipe_screen *
+swrast_screen_create(struct sw_winsys *winsys)
+{
+   const char *default_driver;
+   const char *driver;
+   struct pipe_screen *screen = NULL;
+
+#if defined(GALLIUM_CELL)
+   default_driver = "cell";
+#elif defined(GALLIUM_LLVMPIPE)
+   default_driver = "llvmpipe";
+#elif defined(GALLIUM_SOFTPIPE)
+   default_driver = "softpipe";
+#else
+   default_driver = "";
+#endif
+
+   driver = debug_get_option("GALLIUM_DRIVER", default_driver);
+
+#if defined(GALLIUM_CELL)
+   if (screen == NULL && strcmp(driver, "cell") == 0)
+      screen = cell_create_screen( winsys );
+#endif
+
+#if defined(GALLIUM_LLVMPIPE)
+   if (screen == NULL && strcmp(driver, "llvmpipe") == 0)
+      screen = llvmpipe_create_screen( winsys );
+#endif
+
+#if defined(GALLIUM_SOFTPIPE)
+   if (screen == NULL)
+      screen = softpipe_create_screen( winsys );
+#endif
+
+   return gallium_wrap_screen( screen );
+}
+