Home | History | Annotate | Download | only in i965 
      1 /*
      2  Copyright (C) Intel Corp.  2006.  All Rights Reserved.
      3  Intel funded Tungsten Graphics to
      4  develop this 3D driver.
      5 
      6  Permission is hereby granted, free of charge, to any person obtaining
      7  a copy of this software and associated documentation files (the
      8  "Software"), to deal in the Software without restriction, including
      9  without limitation the rights to use, copy, modify, merge, publish,
     10  distribute, sublicense, and/or sell copies of the Software, and to
     11  permit persons to whom the Software is furnished to do so, subject to
     12  the following conditions:
     13 
     14  The above copyright notice and this permission notice (including the
     15  next paragraph) shall be included in all copies or substantial
     16  portions of the Software.
     17 
     18  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
     19  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
     20  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
     21  IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
     22  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
     23  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
     24  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
     25 
     26  **********************************************************************/
     27  /*
     28   * Authors:
     29   *   Keith Whitwell <keithw (at) vmware.com>
     30   */
     31 
     32 
     33 #ifndef BRW_UTIL_H
     34 #define BRW_UTIL_H
     35 
     36 #include "brw_context.h"
     37 #include "main/framebuffer.h"
     38 
     39 extern GLuint brw_translate_blend_factor( GLenum factor );
     40 extern GLuint brw_translate_blend_equation( GLenum mode );
     41 extern GLenum brw_fix_xRGB_alpha(GLenum function);
     42 
     43 static inline uint32_t
     44 brw_get_line_width(struct brw_context *brw)
     45 {
     46    /* From the OpenGL 4.4 spec:
     47     *
     48     * "The actual width of non-antialiased lines is determined by rounding
     49     * the supplied width to the nearest integer, then clamping it to the
     50     * implementation-dependent maximum non-antialiased line width."
     51     */
     52    float line_width =
     53       CLAMP(!_mesa_is_multisample_enabled(&brw->ctx) && !brw->ctx.Line.SmoothFlag
     54             ? roundf(brw->ctx.Line.Width) : brw->ctx.Line.Width,
     55             0.0f, brw->ctx.Const.MaxLineWidth);
     56    uint32_t line_width_u3_7 = U_FIXED(line_width, 7);
     57 
     58    /* Line width of 0 is not allowed when MSAA enabled */
     59    if (_mesa_is_multisample_enabled(&brw->ctx)) {
     60       if (line_width_u3_7 == 0)
     61          line_width_u3_7 = 1;
     62    } else if (brw->ctx.Line.SmoothFlag && line_width < 1.5f) {
     63       /* For 1 pixel line thickness or less, the general
     64        * anti-aliasing algorithm gives up, and a garbage line is
     65        * generated.  Setting a Line Width of 0.0 specifies the
     66        * rasterization of the "thinnest" (one-pixel-wide),
     67        * non-antialiased lines.
     68        *
     69        * Lines rendered with zero Line Width are rasterized using
     70        * Grid Intersection Quantization rules as specified by
     71        * bspec section 6.3.12.1 Zero-Width (Cosmetic) Line
     72        * Rasterization.
     73        */
     74       line_width_u3_7 = 0;
     75    }
     76 
     77    return line_width_u3_7;
     78 }
     79 
     80 #endif
     81