Files
fs2open.github.com/code/graphics/gradient.cpp
T
2002-08-01 01:41:11 +00:00

212 lines
4.5 KiB
C++

/*
* Copyright (C) Volition, Inc. 1999. All rights reserved.
*
* All source code herein is the property of Volition, Inc. You may not sell
* or otherwise commercially exploit the source or things you created based on the
* source.
*
*/
/*
* $Logfile: /Freespace2/code/Graphics/Gradient.cpp $
* $Revision: 2.2 $
* $Date: 2002-08-01 01:41:05 $
* $Author: penguin $
*
* Routines to draw rectangular gradients.
*
* $Log: not supported by cvs2svn $
* Revision 2.1 2002/07/29 20:12:31 penguin
* added #ifdef _WIN32 around windows-specific system headers
*
* Revision 2.0 2002/06/03 04:02:22 penguin
* Warpcore CVS sync
*
* Revision 1.1 2002/05/02 18:03:07 mharris
* Initial checkin - converted filenames and includes to lower case
*
*
* 3 12/02/98 5:47p Dave
* Put in interface xstr code. Converted barracks screen to new format.
*
* 2 10/07/98 10:52a Dave
* Initial checkin.
*
* 1 10/07/98 10:49a Dave
*
* 17 5/06/98 5:30p John
* Removed unused cfilearchiver. Removed/replaced some unused/little used
* graphics functions, namely gradient_h and _v and pixel_sp. Put in new
* DirectX header files and libs that fixed the Direct3D alpha blending
* problems.
*
* 16 3/10/98 4:18p John
* Cleaned up graphics lib. Took out most unused gr functions. Made D3D
* & Glide have popups and print screen. Took out all >8bpp software
* support. Made Fred zbuffer. Made zbuffer allocate dynamically to
* support Fred. Made zbuffering key off of functions rather than one
* global variable.
*
* 15 1/19/98 6:15p John
* Fixed all my Optimized Build compiler warnings
*
* 14 11/30/97 4:04p John
*
* 13 11/30/97 12:18p John
* added more 24 & 32-bpp primitives
*
* 12 10/19/97 12:55p John
* new code to lock / unlock surfaces for smooth directx integration.
*
* 11 10/14/97 4:50p John
* more 16 bpp stuff.
*
* 10 10/14/97 8:08a John
* added a bunch more 16 bit support
*
* 9 10/09/97 5:23p John
* Added support for more 16-bpp functions
*
* 8 6/11/97 1:12p John
* Started fixing all the text colors in the game.
*
* 7 5/12/97 12:27p John
* Restructured Graphics Library to add support for multiple renderers.
*
* 6 12/12/96 4:59p Lawrance
* made clipping for horizontal and vertical gradient lines right
*
* 5 11/19/96 2:46p Allender
* fix up gradient support for 15bpp
*
* 4 11/18/96 4:34p Allender
* new 16 bit gradient functions
*
* 3 10/27/96 1:21a Lawrance
* added check to avoid divide by zero when calculating gradients
*
* 2 10/26/96 2:56p John
* Got gradient code working.
*
* 1 10/26/96 1:45p John
* Initial skeletion code.
*
* $NoKeywords: $
*/
#ifdef _WIN32
#include <windows.h>
#include <windowsx.h>
#endif
#include "graphics/2d.h"
#include "graphics/grinternal.h"
#include "graphics/gradient.h"
#include "math/floating.h"
#include "graphics/line.h"
#include "palman/palman.h"
void gr8_gradient(int x1,int y1,int x2,int y2)
{
#ifndef HARDWARE_ONLY
int i;
int xstep,ystep;
int clipped = 0, swapped=0;
ubyte *xlat_table;
int l=0, dl=0;
if (!Current_alphacolor) {
gr_line( x1, y1, x2, y2 );
return;
}
INT_CLIPLINE(x1,y1,x2,y2,gr_screen.clip_left,gr_screen.clip_top,gr_screen.clip_right,gr_screen.clip_bottom,return,clipped=1,swapped=1);
int dy=y2-y1;
int dx=x2-x1;
int error_term=0;
if ( dx==0 && dy==0 ) {
return;
}
gr_lock();
ubyte *dptr = GR_SCREEN_PTR(ubyte,x1,y1);
xlat_table = (ubyte *)&Current_alphacolor->table.lookup[0][0];
if(dy<0) {
dy=-dy;
ystep=-gr_screen.rowsize / gr_screen.bytes_per_pixel;
} else {
ystep=gr_screen.rowsize / gr_screen.bytes_per_pixel;
}
if(dx<0) {
dx=-dx;
xstep=-1;
} else {
xstep=1;
}
if(dx>dy) {
if (!swapped) {
l = 14<<8;
dl = (-14<<8) / dx;
} else {
l = 0;
dl = (14<<8) / dx;
}
for(i=0;i<dx;i++) {
*dptr = xlat_table[(l&0xF00)|*dptr];
l += dl;
dptr += xstep;
error_term+=dy;
if(error_term>dx) {
error_term-=dx;
dptr+=ystep;
}
}
*dptr = xlat_table[(l&0xF00)|*dptr];
} else {
if (!swapped) {
l = 14<<8;
dl = (-14<<8) / dy;
} else {
l = 0;
dl = (14<<8) / dy;
}
for(i=0;i<dy;i++) {
*dptr = xlat_table[(l&0xF00)|*dptr];
l += dl;
dptr += ystep;
error_term+=dx;
if(error_term>0) {
error_term-=dy;
dptr+=xstep;
}
}
*dptr = xlat_table[(l&0xF00)|*dptr];
}
gr_unlock();
#else
Int3();
#endif
}