reactos/dll/opengl/mesa/scissor.c
Jérôme Gardou 5f2bebf7a5 [OPENGL32][MESA] Downgrade Mesa library to version 2.6
With this commit, we now use a forked version of MESA which only supports OpenGL 1.1, like the windows implementation does.
It exposes :
  - The same pixel formats
  - The same set of extensions
  - Nothing more
All of this without taking 10% of your build time.
If you need a more modern option, look at the MESA package from Rapps, which is (and must be) maintained outside of this code tree.
CORE-7499
2019-01-19 14:23:54 +01:00

133 lines
3.4 KiB
C

/* $Id: scissor.c,v 1.6 1997/11/25 03:38:58 brianp Exp $ */
/*
* Mesa 3-D graphics library
* Version: 2.5
* Copyright (C) 1995-1997 Brian Paul
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
* $Log: scissor.c,v $
* Revision 1.6 1997/11/25 03:38:58 brianp
* small optimization to gl_Scissor() (Daryll Strauss)
*
* Revision 1.5 1997/07/24 01:21:56 brianp
* changed precompiled header symbol from PCH to PC_HEADER
*
* Revision 1.4 1997/05/28 03:26:29 brianp
* added precompiled header (PCH) support
*
* Revision 1.3 1997/05/17 03:17:50 brianp
* faster gl_scissor_span() from Mats Lofkvist
*
* Revision 1.2 1996/09/15 14:18:37 brianp
* now use GLframebuffer and GLvisual
*
* Revision 1.1 1996/09/13 01:38:16 brianp
* Initial revision
*
*/
#ifdef PC_HEADER
#include "all.h"
#else
#include "context.h"
#include "macros.h"
#include "dlist.h"
#include "scissor.h"
#include "types.h"
#endif
void gl_Scissor( GLcontext *ctx,
GLint x, GLint y, GLsizei width, GLsizei height )
{
if (width<0 || height<0) {
gl_error( ctx, GL_INVALID_VALUE, "glScissor" );
return;
}
if (INSIDE_BEGIN_END(ctx)) {
gl_error( ctx, GL_INVALID_OPERATION, "glBegin" );
return;
}
if (x!=ctx->Scissor.X || y!=ctx->Scissor.Y ||
width!=ctx->Scissor.Width || height!=ctx->Scissor.Height) {
ctx->Scissor.X = x;
ctx->Scissor.Y = y;
ctx->Scissor.Width = width;
ctx->Scissor.Height = height;
ctx->NewState |= NEW_ALL; /* TODO: this is overkill */
}
}
/*
* Apply the scissor test to a span of pixels.
* Return: 0 = all pixels in the span are outside the scissor box.
* 1 = one or more pixels passed the scissor test.
*/
GLint gl_scissor_span( GLcontext *ctx,
GLuint n, GLint x, GLint y, GLubyte mask[] )
{
/* first check if whole span is outside the scissor box */
if (y<ctx->Buffer->Ymin || y>ctx->Buffer->Ymax
|| x>ctx->Buffer->Xmax || x+(GLint)n-1<ctx->Buffer->Xmin) {
return 0;
}
else {
GLint i;
GLint xMin = ctx->Buffer->Xmin;
GLint xMax = ctx->Buffer->Xmax;
for (i=0; x+i < xMin; i++) {
mask[i] = 0;
}
for (i=(GLint)n-1; x+i > xMax; i--) {
mask[i] = 0;
}
return 1;
}
}
/*
* Apply the scissor test to an array of pixels.
*/
GLuint gl_scissor_pixels( GLcontext *ctx,
GLuint n, const GLint x[], const GLint y[],
GLubyte mask[] )
{
GLint xmin = ctx->Buffer->Xmin;
GLint xmax = ctx->Buffer->Xmax;
GLint ymin = ctx->Buffer->Ymin;
GLint ymax = ctx->Buffer->Ymax;
GLuint i;
for (i=0;i<n;i++) {
mask[i] &= (x[i]>=xmin) & (x[i]<=xmax) & (y[i]>=ymin) & (y[i]<=ymax);
}
return 1;
}