src/mesa/drivers/dri/i965/gen6_clip_state.c

   1 /*
   2  * Copyright © 2009 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *    Eric Anholt <eric@anholt.net>
  25  *
  26  */
  27
  28 #include "brw_context.h"
  29 #include "brw_state.h"
  30 #include "brw_defines.h"
  31 #include "brw_util.h"
  32 #include "intel_batchbuffer.h"
  33
  34 static void
  35 upload_clip_state(struct brw_context *brw)
  36 {
  37    struct intel_context *intel = &brw->intel;
  38    struct gl_context *ctx = &intel->ctx;
  39    uint32_t depth_clamp = 0;
  40    uint32_t provoking, userclip;
  41    uint32_t nonperspective_barycentric_enable_flag = 0;
  42
  43    /* CACHE_NEW_WM_PROG */
  44    if (brw->wm.prog_data->barycentric_interp_modes &
  45        (1 << BRW_WM_NONPERSPECTIVE_PIXEL_BARYCENTRIC)) {
  46       nonperspective_barycentric_enable_flag =
  47          GEN6_CLIP_NON_PERSPECTIVE_BARYCENTRIC_ENABLE;
  48    }
  49
  50    if (!ctx->Transform.DepthClamp)
  51       depth_clamp = GEN6_CLIP_Z_TEST;
  52
  53    /* _NEW_LIGHT */
  54    if (ctx->Light.ProvokingVertex == GL_FIRST_VERTEX_CONVENTION) {
  55       provoking =
  56          (0 << GEN6_CLIP_TRI_PROVOKE_SHIFT) |
  57          (1 << GEN6_CLIP_TRIFAN_PROVOKE_SHIFT) |
  58          (0 << GEN6_CLIP_LINE_PROVOKE_SHIFT);
  59    } else {
  60       provoking =
  61          (2 << GEN6_CLIP_TRI_PROVOKE_SHIFT) |
  62          (2 << GEN6_CLIP_TRIFAN_PROVOKE_SHIFT) |
  63          (1 << GEN6_CLIP_LINE_PROVOKE_SHIFT);
  64    }
  65
  66    /* _NEW_TRANSFORM */
  67    userclip = ctx->Transform.ClipPlanesEnabled;
  68
  69    BEGIN_BATCH(4);
  70    OUT_BATCH(_3DSTATE_CLIP << 16 | (4 - 2));
  71    OUT_BATCH(GEN6_CLIP_STATISTICS_ENABLE);
  72    OUT_BATCH(GEN6_CLIP_ENABLE |
  73              GEN6_CLIP_API_OGL |
  74              GEN6_CLIP_MODE_NORMAL |
  75              nonperspective_barycentric_enable_flag |
  76              GEN6_CLIP_XY_TEST |
  77              userclip << GEN6_USER_CLIP_CLIP_DISTANCES_SHIFT |
  78              depth_clamp |
  79              provoking);
  80    OUT_BATCH(U_FIXED(0.125, 3) << GEN6_CLIP_MIN_POINT_WIDTH_SHIFT |
  81              U_FIXED(255.875, 3) << GEN6_CLIP_MAX_POINT_WIDTH_SHIFT |
  82              GEN6_CLIP_FORCE_ZERO_RTAINDEX);
  83    ADVANCE_BATCH();
  84 }
  85
  86 const struct brw_tracked_state gen6_clip_state = {
  87    .dirty = {
  88       .mesa  = _NEW_TRANSFORM | _NEW_LIGHT,
  89       .brw   = (BRW_NEW_CONTEXT),
  90       .cache = CACHE_NEW_WM_PROG
  91    },
  92    .emit = upload_clip_state,
  93 };