;
; Command & Conquer Red Alert(tm)
; Copyright 2025 Electronic Arts Inc.
;
; This program is free software: you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation, either version 3 of the License, or
; (at your option) any later version.
;
; This program is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
; GNU General Public License for more details.
;
; You should have received a copy of the GNU General Public License
; along with this program. If not, see <http://www.gnu.org/licenses/>.
;
;***************************************************************************
;** C O N F I D E N T I A L --- W E S T W O O D A S S O C I A T E S **
;***************************************************************************
;* *
;* Project Name : Westwood 32 bit Library *
;* *
;* File Name : TOPAGE.ASM *
;* *
;* Programmer : Phil W. Gorrow *
;* *
;* Start Date : June 8, 1994 *
;* *
;* Last Update : June 15, 1994 [PWG] *
;* *
;*-------------------------------------------------------------------------*
;* Functions: *
;* Buffer_To_Page -- Copies a linear buffer to a virtual viewport *
;* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - *
IDEAL
P386
MODEL USE32 FLAT
TRANSP equ 0
INCLUDE ".\drawbuff.inc"
INCLUDE ".\gbuffer.inc"
CODESEG
;***************************************************************************
;* VVC::TOPAGE -- Copies a linear buffer to a virtual viewport *
;* *
;* INPUT: WORD x_pixel - x pixel on viewport to copy from *
;* WORD y_pixel - y pixel on viewport to copy from *
;* WORD pixel_width - the width of copy region *
;* WORD pixel_height - the height of copy region *
;* BYTE * src - buffer to copy from *
;* VVPC * dest - virtual viewport to copy to *
;* *
;* OUTPUT: none *
;* *
;* WARNINGS: Coordinates and dimensions will be adjusted if they exceed *
;* the boundaries. In the event that no adjustment is *
;* possible this routine will abort. If the size of the *
;* region to copy exceeds the size passed in for the buffer *
;* the routine will automatically abort. *
;* *
;* HISTORY: *
;* 06/15/1994 PWG : Created. *
;*=========================================================================*
PROC Buffer_To_Page C near
USES eax,ebx,ecx,edx,esi,edi
;*===================================================================
;* define the arguements that our function takes.
;*===================================================================
ARG x_pixel :DWORD ; x pixel position in source
ARG y_pixel :DWORD ; y pixel position in source
ARG pixel_width :DWORD ; width of rectangle to blit
ARG pixel_height:DWORD ; height of rectangle to blit
ARG src :DWORD ; this is a member function
ARG dest :DWORD ; what are we blitting to
; ARG trans :DWORD ; do we deal with transparents?
;*===================================================================
; Define some locals so that we can handle things quickly
;*===================================================================
LOCAL x1_pixel :dword
LOCAL y1_pixel :dword
local scr_x : dword
local scr_y : dword
LOCAL dest_ajust_width:DWORD
LOCAL scr_ajust_width:DWORD
LOCAL dest_area : dword
cmp [ src ] , 0
jz ??real_out
; Clip dest Rectangle against source Window boundaries.
mov [ scr_x ] , 0
mov [ scr_y ] , 0
mov esi , [ dest ] ; get ptr to dest
xor ecx , ecx
xor edx , edx
mov edi , [ (GraphicViewPort esi) . GVPWidth ] ; get width into register
mov ebx , [ x_pixel ]
mov eax , [ x_pixel ]
add ebx , [ pixel_width ]
shld ecx , eax , 1
mov [ x1_pixel ] , ebx
inc edi
shld edx , ebx , 1
sub eax , edi
sub ebx , edi
shld ecx , eax , 1
shld edx , ebx , 1
mov edi,[ ( GraphicViewPort esi) . GVPHeight ] ; get height into register
mov ebx , [ y_pixel ]
mov eax , [ y_pixel ]
add ebx , [ pixel_height ]
shld ecx , eax , 1
mov [ y1_pixel ] , ebx
inc edi
shld edx , ebx , 1
sub eax , edi
sub ebx , edi
shld ecx , eax , 1
shld edx , ebx , 1
xor cl , 5
xor dl , 5
mov al , cl
test dl , cl
jnz ??real_out
or al , dl
jz ??do_blit
test cl , 1000b
jz ??dest_left_ok
mov eax , [ x_pixel ]
neg eax
mov [ x_pixel ] , 0
mov [ scr_x ] , eax
??dest_left_ok:
test cl , 0010b
jz ??dest_bottom_ok
mov eax , [ y_pixel ]
neg eax
mov [ y_pixel ] , 0
mov [ scr_y ] , eax
??dest_bottom_ok:
test dl , 0100b
jz ??dest_right_ok
mov eax , [ (GraphicViewPort esi) . GVPWidth ] ; get width into register
mov [ x1_pixel ] , eax
??dest_right_ok:
test dl , 0001b
jz ??do_blit
mov eax , [ (GraphicViewPort esi) . GVPHeight ] ; get width into register
mov [ y1_pixel ] , eax
??do_blit:
cld
mov eax , [ (GraphicViewPort esi) . GVPXAdd ]
add eax , [ (GraphicViewPort esi) . GVPWidth ]
add eax , [ (GraphicViewPort esi) . GVPPitch ]
mov edi , [ (GraphicViewPort esi) . GVPOffset ]
mov ecx , eax
mul [ y_pixel ]
add edi , [ x_pixel ]
add edi , eax
add ecx , [ x_pixel ]
sub ecx , [ x1_pixel ]
mov [ dest_ajust_width ] , ecx
mov esi , [ src ]
mov eax , [ pixel_width ]
sub eax , [ x1_pixel ]
add eax , [ x_pixel ]
mov [ scr_ajust_width ] , eax
mov eax , [ scr_y ]
mul [ pixel_width ]
add eax , [ scr_x ]
add esi , eax
mov edx , [ y1_pixel ]
mov eax , [ x1_pixel ]
sub edx , [ y_pixel ]
jle ??real_out
sub eax , [ x_pixel ]
jle ??real_out
; ********************************************************************
; Forward bitblit only
IF TRANSP
test [ trans ] , 1
jnz ??forward_Blit_trans
ENDIF
; the inner loop is so efficient that
; the optimal consept no longer apply because
; the optimal byte have to by a number greather than 9 bytes
cmp eax , 10
jl ??forward_loop_bytes
??forward_loop_dword:
mov ecx , edi
mov ebx , eax
neg ecx
and ecx , 3
sub ebx , ecx
rep movsb
mov ecx , ebx
shr ecx , 2
rep movsd
mov ecx , ebx
and ecx , 3
rep movsb
add esi , [ scr_ajust_width ]
add edi , [ dest_ajust_width ]
dec edx
jnz ??forward_loop_dword
ret
??forward_loop_bytes:
mov ecx , eax
rep movsb
add esi , [ scr_ajust_width ]
add edi , [ dest_ajust_width ]
dec edx ; decrement the height
jnz ??forward_loop_bytes
ret
IF TRANSP
??forward_Blit_trans:
mov ecx , eax
and ecx , 01fh
lea ecx , [ ecx + ecx * 4 ]
neg ecx
shr eax , 5
lea ecx , [ ??transp_reference + ecx * 2 ]
mov [ y1_pixel ] , ecx
??forward_loop_trans:
mov ecx , eax
jmp [ y1_pixel ]
??forward_trans_line:
REPT 32
local transp_pixel
mov bl , [ esi ]
inc esi
test bl , bl
jz transp_pixel
mov [ edi ] , bl
transp_pixel:
inc edi
ENDM
??transp_reference:
dec ecx
jge ??forward_trans_line
add esi , [ scr_ajust_width ]
add edi , [ dest_ajust_width ]
dec edx
jnz ??forward_loop_trans
ret
ENDIF
??real_out:
ret
ENDP Buffer_To_Page
END