static void
upload_clip_state(struct brw_context *brw)
{
struct gl_context *ctx = &brw->ctx;
/* BRW_NEW_META_IN_PROGRESS */
uint32_t dw1 = brw->meta_in_progress ? 0 : GEN6_CLIP_STATISTICS_ENABLE;
uint32_t dw2 = 0;
/* _NEW_BUFFERS */
struct gl_framebuffer *fb = ctx->DrawBuffer;
/* BRW_NEW_FS_PROG_DATA */
if (brw->wm.prog_data->barycentric_interp_modes &
BRW_WM_NONPERSPECTIVE_BARYCENTRIC_BITS) {
dw2 |= GEN6_CLIP_NON_PERSPECTIVE_BARYCENTRIC_ENABLE;
}
dw1 |= brw->vs.prog_data->base.cull_distance_mask;
if (brw->gen >= 7)
dw1 |= GEN7_CLIP_EARLY_CULL;
if (brw->gen == 7) {
/* _NEW_POLYGON */
if (ctx->Polygon._FrontBit == _mesa_is_user_fbo(fb))
dw1 |= GEN7_CLIP_WINDING_CCW;
if (ctx->Polygon.CullFlag) {
switch (ctx->Polygon.CullFaceMode) {
case GL_FRONT:
dw1 |= GEN7_CLIP_CULLMODE_FRONT;
break;
case GL_BACK:
dw1 |= GEN7_CLIP_CULLMODE_BACK;
break;
case GL_FRONT_AND_BACK:
dw1 |= GEN7_CLIP_CULLMODE_BOTH;
break;
default:
unreachable("Should not get here: invalid CullFlag");
}
} else {
dw1 |= GEN7_CLIP_CULLMODE_NONE;
}
}
if (brw->gen < 8 && !ctx->Transform.DepthClamp)
dw2 |= GEN6_CLIP_Z_TEST;
/* _NEW_LIGHT */
if (ctx->Light.ProvokingVertex == GL_FIRST_VERTEX_CONVENTION) {
dw2 |=
(0 << GEN6_CLIP_TRI_PROVOKE_SHIFT) |
(1 << GEN6_CLIP_TRIFAN_PROVOKE_SHIFT) |
(0 << GEN6_CLIP_LINE_PROVOKE_SHIFT);
} else {
dw2 |=
(2 << GEN6_CLIP_TRI_PROVOKE_SHIFT) |
(2 << GEN6_CLIP_TRIFAN_PROVOKE_SHIFT) |
(1 << GEN6_CLIP_LINE_PROVOKE_SHIFT);
}
/* _NEW_TRANSFORM */
dw2 |= (ctx->Transform.ClipPlanesEnabled <<
GEN6_USER_CLIP_CLIP_DISTANCES_SHIFT);
if (ctx->Transform.ClipDepthMode == GL_ZERO_TO_ONE)
dw2 |= GEN6_CLIP_API_D3D;
else
dw2 |= GEN6_CLIP_API_OGL;
dw2 |= GEN6_CLIP_GB_TEST;
/* We need to disable guardband clipping if the guardband (which we always
* program to the maximum screen-space bounding box of 8K x 8K) will be
* smaller than the viewport.
*
* Closely examining the clip determination formulas in the documentation
* reveals that objects will be discarded entirely if they're outside the
* (small) guardband, even if they're within the (large) viewport:
*
* TR = TR_GB || TR_VPXY || TR_VPZ || TR_UC || TR_NEGW
* TA = !TR && TA_GB && TA_VPZ && TA_NEGW
* MC = !(TA || TR)
*
* (TA is "Trivial Accept", TR is "Trivial Reject", MC is "Must Clip".)
*
* Disabling guardband clipping removes the TR_GB condition, which means
* they'll be considered MC ("Must Clip") unless they're rejected for
* some other reason.
*
* Note that there is no TA_VPXY condition. If there were, objects entirely
* inside a 16384x16384 viewport would be trivially accepted, breaking the
* "objects must have a screenspace bounding box not exceeding 8K in the X
* or Y direction" restriction. Instead, they're clipped.
*/
for (unsigned i = 0; i < ctx->Const.MaxViewports; i++) {
if (ctx->ViewportArray[i].Width > 8192 ||
ctx->ViewportArray[i].Height > 8192) {
dw2 &= ~GEN6_CLIP_GB_TEST;
break;
}
}
/* If the viewport dimensions are smaller than the drawable dimensions,
* we have to disable guardband clipping prior to Gen8. We always program
* the guardband to a fixed size, which is almost always larger than the
* viewport. Any geometry which intersects the viewport but lies within
* the guardband would bypass the 3D clipping stage, so it wouldn't be
* clipped to the viewport. Rendering would happen beyond the viewport,
* but still inside the drawable.
*
* Gen8+ introduces a viewport extents test which restricts rendering to
* the viewport, so we can ignore this restriction.
*/
if (brw->gen < 8) {
const float fb_width = (float)_mesa_geometric_width(fb);
const float fb_height = (float)_mesa_geometric_height(fb);
for (unsigned i = 0; i < ctx->Const.MaxViewports; i++) {
if (ctx->ViewportArray[i].X != 0 ||
ctx->ViewportArray[i].Y != 0 ||
ctx->ViewportArray[i].Width != fb_width ||
ctx->ViewportArray[i].Height != fb_height) {
dw2 &= ~GEN6_CLIP_GB_TEST;
break;
}
}
}
/* BRW_NEW_RASTERIZER_DISCARD */
if (ctx->RasterDiscard) {
dw2 |= GEN6_CLIP_MODE_REJECT_ALL;
if (brw->gen == 6) {
perf_debug("Rasterizer discard is currently implemented via the "
"clipper; having the GS not write primitives would "
"likely be faster.\n");
}
}
uint32_t enable;
if (brw->primitive == _3DPRIM_RECTLIST)
enable = 0;
else
enable = GEN6_CLIP_ENABLE;
if (!is_drawing_points(brw) && !is_drawing_lines(brw))
dw2 |= GEN6_CLIP_XY_TEST;
/* BRW_NEW_VUE_MAP_GEOM_OUT */
const int max_vp_index =
(brw->vue_map_geom_out.slots_valid & VARYING_BIT_VIEWPORT) != 0 ?
ctx->Const.MaxViewports : 1;
BEGIN_BATCH(4);
OUT_BATCH(_3DSTATE_CLIP << 16 | (4 - 2));
OUT_BATCH(dw1);
OUT_BATCH(enable |
GEN6_CLIP_MODE_NORMAL |
dw2);
OUT_BATCH(U_FIXED(0.125, 3) << GEN6_CLIP_MIN_POINT_WIDTH_SHIFT |
U_FIXED(255.875, 3) << GEN6_CLIP_MAX_POINT_WIDTH_SHIFT |
(_mesa_geometric_layers(fb) > 0 ? 0 : GEN6_CLIP_FORCE_ZERO_RTAINDEX) |
((max_vp_index - 1) & GEN6_CLIP_MAX_VP_INDEX_MASK));
ADVANCE_BATCH();
}
static void
upload_sf_state(struct brw_context *brw)
{
struct gl_context *ctx = &brw->ctx;
uint32_t dw1, dw2, dw3;
float point_size;
/* _NEW_BUFFERS */
bool render_to_fbo = _mesa_is_user_fbo(ctx->DrawBuffer);
const bool multisampled_fbo = _mesa_geometric_samples(ctx->DrawBuffer) > 1;
dw1 = GEN6_SF_STATISTICS_ENABLE;
if (brw->sf.viewport_transform_enable)
dw1 |= GEN6_SF_VIEWPORT_TRANSFORM_ENABLE;
/* _NEW_BUFFERS */
dw1 |= (brw_depthbuffer_format(brw) << GEN7_SF_DEPTH_BUFFER_SURFACE_FORMAT_SHIFT);
/* _NEW_POLYGON */
if (ctx->Polygon._FrontBit == render_to_fbo)
dw1 |= GEN6_SF_WINDING_CCW;
if (ctx->Polygon.OffsetFill)
dw1 |= GEN6_SF_GLOBAL_DEPTH_OFFSET_SOLID;
if (ctx->Polygon.OffsetLine)
dw1 |= GEN6_SF_GLOBAL_DEPTH_OFFSET_WIREFRAME;
if (ctx->Polygon.OffsetPoint)
dw1 |= GEN6_SF_GLOBAL_DEPTH_OFFSET_POINT;
switch (ctx->Polygon.FrontMode) {
case GL_FILL:
dw1 |= GEN6_SF_FRONT_SOLID;
break;
case GL_LINE:
dw1 |= GEN6_SF_FRONT_WIREFRAME;
break;
case GL_POINT:
dw1 |= GEN6_SF_FRONT_POINT;
break;
default:
unreachable("not reached");
}
switch (ctx->Polygon.BackMode) {
case GL_FILL:
dw1 |= GEN6_SF_BACK_SOLID;
break;
case GL_LINE:
dw1 |= GEN6_SF_BACK_WIREFRAME;
break;
case GL_POINT:
dw1 |= GEN6_SF_BACK_POINT;
break;
default:
unreachable("not reached");
}
dw2 = 0;
if (ctx->Polygon.CullFlag) {
switch (ctx->Polygon.CullFaceMode) {
case GL_FRONT:
dw2 |= GEN6_SF_CULL_FRONT;
break;
case GL_BACK:
dw2 |= GEN6_SF_CULL_BACK;
break;
case GL_FRONT_AND_BACK:
dw2 |= GEN6_SF_CULL_BOTH;
break;
default:
unreachable("not reached");
}
} else {
dw2 |= GEN6_SF_CULL_NONE;
}
/* _NEW_SCISSOR _NEW_POLYGON BRW_NEW_GEOMETRY_PROGRAM BRW_NEW_PRIMITIVE */
if (ctx->Scissor.EnableFlags ||
is_drawing_points(brw) || is_drawing_lines(brw))
dw2 |= GEN6_SF_SCISSOR_ENABLE;
/* _NEW_LINE */
{
uint32_t line_width_u3_7 = brw_get_line_width(brw);
dw2 |= line_width_u3_7 << GEN6_SF_LINE_WIDTH_SHIFT;
}
if (ctx->Line.SmoothFlag) {
dw2 |= GEN6_SF_LINE_AA_ENABLE;
dw2 |= GEN6_SF_LINE_END_CAP_WIDTH_1_0;
}
if (ctx->Line.StippleFlag && brw->is_haswell) {
dw2 |= HSW_SF_LINE_STIPPLE_ENABLE;
}
/* _NEW_MULTISAMPLE */
if (multisampled_fbo && ctx->Multisample.Enabled)
dw2 |= GEN6_SF_MSRAST_ON_PATTERN;
/* FINISHME: Last Pixel Enable? Vertex Sub Pixel Precision Select?
*/
dw3 = GEN6_SF_LINE_AA_MODE_TRUE;
/* _NEW_PROGRAM | _NEW_POINT */
if (!(ctx->VertexProgram.PointSizeEnabled || ctx->Point._Attenuated))
dw3 |= GEN6_SF_USE_STATE_POINT_WIDTH;
/* Clamp to ARB_point_parameters user limits */
point_size = CLAMP(ctx->Point.Size, ctx->Point.MinSize, ctx->Point.MaxSize);
/* Clamp to the hardware limits and convert to fixed point */
dw3 |= U_FIXED(CLAMP(point_size, 0.125f, 255.875f), 3);
/* _NEW_LIGHT */
if (ctx->Light.ProvokingVertex != GL_FIRST_VERTEX_CONVENTION) {
dw3 |=
(2 << GEN6_SF_TRI_PROVOKE_SHIFT) |
(2 << GEN6_SF_TRIFAN_PROVOKE_SHIFT) |
(1 << GEN6_SF_LINE_PROVOKE_SHIFT);
} else {
dw3 |= (1 << GEN6_SF_TRIFAN_PROVOKE_SHIFT);
}
BEGIN_BATCH(7);
OUT_BATCH(_3DSTATE_SF << 16 | (7 - 2));
OUT_BATCH(dw1);
OUT_BATCH(dw2);
OUT_BATCH(dw3);
OUT_BATCH_F(ctx->Polygon.OffsetUnits * 2); /* constant. copied from gen4 */
OUT_BATCH_F(ctx->Polygon.OffsetFactor); /* scale */
OUT_BATCH_F(ctx->Polygon.OffsetClamp); /* global depth offset clamp */
ADVANCE_BATCH();
}