Bugfix SDL2 surface init + add some labels in UI

yaglitch.asm

 	jz sdl_error
 	pop rcx
 	pop rcx
+
+	%ifdef SDL2
+		; call memeset to alloc pixels
+		push rax
+		mov rdi, rax
+		call SDL_LockSurface
+
+		xor rdx, rdx
+		xor rcx, rcx
+		MOV_surf_w ecx, visu_surf
+		xor rax, rax
+		MOV_surf_pitch eax, visu_surf
+		mul ecx
+		MOV_surf_pixels rdi, visu_surf
+		xor rsi, rsi
+		;mov rsi, 0xFF ;white
+		mov rdx, rax
+		call SDL_memset ; seems to malloc the pixels
+
+		pop rdi ; surface addr
+		call SDL_UnlockSurface
+	%endif
+
 	; RAZ surface & blit
-	call clear_screen
+	;call clear_screen ;useless
 
 	%ifdef MIX_AUDIO
 		; init callback heap infos

yaglitch_ui.asm

 	push rdi
 	call SDL_LockSurface
 
-	%ifdef SDL2
-		xor rdx, rdx
-		xor rcx, rcx
-		MOV_surf_w ecx, visu_surf
-		xor rax, rax
-		MOV_surf_pitch eax, visu_surf
-		mul ecx
-		MOV_surf_pixels rdi, visu_surf
-		xor rsi, rsi
-		;mov rsi, 0xFF ;white
-		mov rdx, rax
-		call SDL_memset ; seems to malloc the pixels
-	%endif
-
 	%ifdef SDL1
 		xor rcx, rcx
 		MOV_surf_w ecx, visu_surf
 	pop rdi ; surface addr
 	call SDL_UnlockSurface
 
+blitflip_visu:
+
 	mov rdi, [visu_surf]
 	xor rsi, rsi
 	mov rdx, [visu_scr]
 	test rax, rax
 	jnz sdl_error
 
+flip_visu:
+
 	%ifdef SDL2
 		mov rdi, [visu_win]
 		call SDL_UpdateWindowSurface