src/mesa/drivers/dri/i965/gen7_clip_state.c

   1 /*
   2  * Copyright © 2011 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
  24 #include "brw_context.h"
  25 #include "brw_state.h"
  26 #include "brw_defines.h"
  27 #include "brw_util.h"
  28 #include "intel_batchbuffer.h"
  29 #include "main/fbobject.h"
  30
  31 static void
  32 upload_clip_state(struct brw_context *brw)
  33 {
  34    struct intel_context *intel = &brw->intel;
  35    struct gl_context *ctx = &intel->ctx;
  36    uint32_t dw1 = GEN6_CLIP_STATISTICS_ENABLE, dw2 = 0;
  37
  38    /* _NEW_BUFFERS */
  39    struct gl_framebuffer *fb = ctx->DrawBuffer;
  40    bool render_to_fbo = _mesa_is_user_fbo(fb);
  41
  42    /* CACHE_NEW_WM_PROG */
  43    if (brw->wm.prog_data->barycentric_interp_modes &
  44        BRW_WM_NONPERSPECTIVE_BARYCENTRIC_BITS) {
  45       dw2 |= GEN6_CLIP_NON_PERSPECTIVE_BARYCENTRIC_ENABLE;
  46    }
  47
  48    dw1 |= GEN7_CLIP_EARLY_CULL;
  49
  50    /* _NEW_POLYGON */
  51    if ((ctx->Polygon.FrontFace == GL_CCW) ^ render_to_fbo)
  52       dw1 |= GEN7_CLIP_WINDING_CCW;
  53
  54    if (ctx->Polygon.CullFlag) {
  55       switch (ctx->Polygon.CullFaceMode) {
  56       case GL_FRONT:
  57          dw1 |= GEN7_CLIP_CULLMODE_FRONT;
  58          break;
  59       case GL_BACK:
  60          dw1 |= GEN7_CLIP_CULLMODE_BACK;
  61          break;
  62       case GL_FRONT_AND_BACK:
  63          dw1 |= GEN7_CLIP_CULLMODE_BOTH;
  64          break;
  65       default:
  66          assert(!"Should not get here: invalid CullFlag");
  67          break;
  68       }
  69    } else {
  70       dw1 |= GEN7_CLIP_CULLMODE_NONE;
  71    }
  72
  73    /* _NEW_TRANSFORM */
  74    if (!ctx->Transform.DepthClamp)
  75       dw2 |= GEN6_CLIP_Z_TEST;
  76
  77    /* _NEW_LIGHT */
  78    if (ctx->Light.ProvokingVertex == GL_FIRST_VERTEX_CONVENTION) {
  79       dw2 |=
  80          (0 << GEN6_CLIP_TRI_PROVOKE_SHIFT) |
  81          (1 << GEN6_CLIP_TRIFAN_PROVOKE_SHIFT) |
  82          (0 << GEN6_CLIP_LINE_PROVOKE_SHIFT);
  83    } else {
  84       dw2 |=
  85          (2 << GEN6_CLIP_TRI_PROVOKE_SHIFT) |
  86          (2 << GEN6_CLIP_TRIFAN_PROVOKE_SHIFT) |
  87          (1 << GEN6_CLIP_LINE_PROVOKE_SHIFT);
  88    }
  89
  90    /* _NEW_TRANSFORM */
  91    dw2 |= (ctx->Transform.ClipPlanesEnabled <<
  92            GEN6_USER_CLIP_CLIP_DISTANCES_SHIFT);
  93
  94    if (ctx->Viewport.X == 0 &&
  95        ctx->Viewport.Y == 0 &&
  96        ctx->Viewport.Width == fb->Width &&
  97        ctx->Viewport.Height == fb->Height) {
  98       dw2 |= GEN6_CLIP_GB_TEST;
  99    }
 100
 101    BEGIN_BATCH(4);
 102    OUT_BATCH(_3DSTATE_CLIP << 16 | (4 - 2));
 103    OUT_BATCH(dw1);
 104    OUT_BATCH(GEN6_CLIP_ENABLE |
 105              GEN6_CLIP_API_OGL |
 106              GEN6_CLIP_MODE_NORMAL |
 107              GEN6_CLIP_XY_TEST |
 108              dw2);
 109    OUT_BATCH(U_FIXED(0.125, 3) << GEN6_CLIP_MIN_POINT_WIDTH_SHIFT |
 110              U_FIXED(255.875, 3) << GEN6_CLIP_MAX_POINT_WIDTH_SHIFT |
 111              GEN6_CLIP_FORCE_ZERO_RTAINDEX);
 112    ADVANCE_BATCH();
 113 }
 114
 115 const struct brw_tracked_state gen7_clip_state = {
 116    .dirty = {
 117       .mesa  = (_NEW_BUFFERS |
 118                 _NEW_POLYGON |
 119                 _NEW_LIGHT |
 120                 _NEW_TRANSFORM),
 121       .brw   = BRW_NEW_CONTEXT,
 122       .cache = CACHE_NEW_WM_PROG
 123    },
 124    .emit = upload_clip_state,
 125 };