view src/hermes/x86_main.asm @ 1554:0ca607a5d173

Fixed bug #84 Date: Sun, 23 Oct 2005 16:39:03 +0200 From: "A. Schmid" <sahib@phreaker.net> Subject: [SDL] no software surfaces with svgalib driver? Hi, I noticed that the SDL (1.2.9) svgalib driver only makes use of linear addressable (framebuffer) video modes. On older systems (like one of mine), linear addressable modes are often not available. Especially for cards with VESA VBE < 2.0 the svgalib vesa driver is unusable, since VESA only supports framebuffering for VBE 2.0 and later. The changes necessary to add support for software surfaces seem to be relatively small. I only had to hack src/video/svga/SDL_svgavideo.c (see attached patch). The code worked fine for me, but it is no more than a proof of concept and should be reviewed (probably has a memory leak when switching modes). It also uses the vgagl library (included in the svgalib package) and needs to be linked against it. -Alex
author Sam Lantinga <slouken@libsdl.org>
date Sun, 19 Mar 2006 12:04:40 +0000
parents 3202d727bb4b
children 393092a3ebf6
line wrap: on
line source

;
; x86 format converters for HERMES
; Some routines Copyright (c) 1998 Christian Nentwich (brn@eleet.mcb.at)
; This source code is licensed under the GNU LGPL
; 
; Please refer to the file COPYING.LIB contained in the distribution for
; licensing conditions		
;
; Most routines are (c) Glenn Fiedler (ptc@gaffer.org), used with permission
; 

BITS 32

GLOBAL _ConvertX86
GLOBAL _x86return
	
GLOBAL _Hermes_X86_CPU

SECTION .text
		
;; _ConvertX86:	 
;; [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
	
_ConvertX86:
	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]

_x86return:	
	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:	
	ret		



;; Hermes_X86_CPU returns the CPUID flags in eax
	
_Hermes_X86_CPU:
	pushfd
	pop eax
	
	mov ecx,eax
	
	xor eax,040000h
	push eax
	
	popfd
	pushfd

	pop eax
	xor eax,ecx
	jz .L1			; Processor is 386

	push ecx
	popfd

	mov eax,ecx
	xor eax,200000h

	push eax
	popfd
	pushfd

	pop eax
	xor eax,ecx
	je .L1
	
	push ebx

	mov eax,1
	cpuid
	mov eax,edx

	pop ebx

.L1:	
	ret

%ifidn __OUTPUT_FORMAT__,elf
section .note.GNU-stack noalloc noexec nowrite progbits
%endif