src/mesa/drivers/dri/i965/gen7_viewport_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 "intel_batchbuffer.h"
  28 #include "main/fbobject.h"
  29
  30 static void
  31 gen7_upload_sf_clip_viewport(struct brw_context *brw)
  32 {
  33    struct gl_context *ctx = &brw->ctx;
  34    const GLfloat depth_scale = 1.0F / ctx->DrawBuffer->_DepthMaxF;
  35    GLfloat y_scale, y_bias;
  36    const bool render_to_fbo = _mesa_is_user_fbo(ctx->DrawBuffer);
  37    const GLfloat *v = ctx->Viewport._WindowMap.m;
  38    struct gen7_sf_clip_viewport *vp;
  39
  40    vp = brw_state_batch(brw, AUB_TRACE_SF_VP_STATE,
  41                         sizeof(*vp), 64, &brw->sf.vp_offset);
  42    /* Also assign to clip.vp_offset in case something uses it. */
  43    brw->clip.vp_offset = brw->sf.vp_offset;
  44
  45    /* According to the "Vertex X,Y Clamping and Quantization" section of the
  46     * Strips and Fans documentation, objects must not have a screen-space
  47     * extents of over 8192 pixels, or they may be mis-rasterized.  The maximum
  48     * screen space coordinates of a small object may larger, but we have no
  49     * way to enforce the object size other than through clipping.
  50     *
  51     * If you're surprised that we set clip to -gbx to +gbx and it seems like
  52     * we'll end up with 16384 wide, note that for a 8192-wide render target,
  53     * we'll end up with a normal (-1, 1) clip volume that just covers the
  54     * drawable.
  55     */
  56    const float maximum_guardband_extent = 8192;
  57    float gbx = maximum_guardband_extent / (float) ctx->Viewport.Width;
  58    float gby = maximum_guardband_extent / (float) ctx->Viewport.Height;
  59
  60    vp->guardband.xmin = -gbx;
  61    vp->guardband.xmax = gbx;
  62    vp->guardband.ymin = -gby;
  63    vp->guardband.ymax = gby;
  64
  65    /* _NEW_BUFFERS */
  66    if (render_to_fbo) {
  67       y_scale = 1.0;
  68       y_bias = 0;
  69    } else {
  70       y_scale = -1.0;
  71       y_bias = ctx->DrawBuffer->Height;
  72    }
  73
  74    /* _NEW_VIEWPORT */
  75    vp->viewport.m00 = v[MAT_SX];
  76    vp->viewport.m11 = v[MAT_SY] * y_scale;
  77    vp->viewport.m22 = v[MAT_SZ] * depth_scale;
  78    vp->viewport.m30 = v[MAT_TX];
  79    vp->viewport.m31 = v[MAT_TY] * y_scale + y_bias;
  80    vp->viewport.m32 = v[MAT_TZ] * depth_scale;
  81
  82    BEGIN_BATCH(2);
  83    OUT_BATCH(_3DSTATE_VIEWPORT_STATE_POINTERS_SF_CL << 16 | (2 - 2));
  84    OUT_BATCH(brw->sf.vp_offset);
  85    ADVANCE_BATCH();
  86 }
  87
  88 const struct brw_tracked_state gen7_sf_clip_viewport = {
  89    .dirty = {
  90       .mesa = _NEW_VIEWPORT | _NEW_BUFFERS,
  91       .brw = BRW_NEW_BATCH,
  92       .cache = 0,
  93    },
  94    .emit = gen7_upload_sf_clip_viewport,
  95 };
  96
  97 /* ----------------------------------------------------- */
  98
  99 static void upload_cc_viewport_state_pointer(struct brw_context *brw)
 100 {
 101    BEGIN_BATCH(2);
 102    OUT_BATCH(_3DSTATE_VIEWPORT_STATE_POINTERS_CC << 16 | (2 - 2));
 103    OUT_BATCH(brw->cc.vp_offset);
 104    ADVANCE_BATCH();
 105 }
 106
 107 const struct brw_tracked_state gen7_cc_viewport_state_pointer = {
 108    .dirty = {
 109       .mesa = 0,
 110       .brw = BRW_NEW_BATCH,
 111       .cache = CACHE_NEW_CC_VP
 112    },
 113    .emit = upload_cc_viewport_state_pointer,
 114 };