view src/hermes/mmx_main.asm @ 1012:f14e3059e138

Date: Mon, 13 Dec 2004 21:28:18 -0500 From: Jonathan Atkins Subject: [SDL] SDL_SaveBMP width bugfix this fixes the pitch versus width difference that can happen (especially for 8bit and 24bit (with the exact RGBAmasks) surfaces) when you use SDL_SaveBMP. The problem was the pitch was used instead of the width, which in some cases is much wider than the screen area you really want to save...making for ugly crud on the saved image borders. This code has been tested with & without pitch overhangs...and with the right masks for 24 bit surfaces. I tested 8,15,16,24,32-0RGB,32-RGBA(with no SDL_SRCALPHA flag).
author Sam Lantinga <slouken@libsdl.org>
date Tue, 14 Dec 2004 06:20:49 +0000
parents 74212992fb08
children da33b7e6d181
line wrap: on
line source

;
; mmx format converter main loops for HERMES
; Some routines Copyright (c) 1998 Christian Nentwich (c.nentwich@cs.ucl.ac.uk)
; This source code is licensed under the GNU LGPL
; 
; Please refer to the file COPYING.LIB contained in the distribution for
; licensing conditions		
;

BITS 32

GLOBAL _ConvertMMX
GLOBAL _mmxreturn


SECTION .text
		
;; _ConvertMMX:	 
;; [ESP+8] ConverterInfo*
;; --------------------------------------------------------------------------
;; ConverterInfo (ebp+..)
;;   0:	void *s_pixels
;;   4:	int s_width
;;   8:	int s_height
;;  12:	int s_add
;;  16:	void *d_pixels
;;  20:	int d_width
;;  24:	int d_height
;;  28:	int d_add
;;  32:	void (*converter_function)() 
;;  36: int32 *lookup
	
_ConvertMMX:
	push ebp
	mov ebp,esp

; Save the registers used by the blitters, necessary for optimized code
	pusha

	mov eax,[ebp+8]

        cmp dword [eax+4],BYTE 0
	je endconvert
	
	mov ebp,eax
	
	mov esi,[ebp+0]
	mov edi,[ebp+16]
	
y_loop:	
	mov ecx,[ebp+4]

	jmp [ebp+32]

_mmxreturn:	
	add esi,[ebp+12]
	add edi,[ebp+28]
	
	dec dword  [ebp+8]
	jnz y_loop

	
; Restore the registers used by the blitters, necessary for optimized code
	popa

	pop ebp

endconvert:
	emms
	
	ret