v3dv: enable shaderClipDistance
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6766>
diff --git a/src/broadcom/vulkan/v3dv_device.c b/src/broadcom/vulkan/v3dv_device.c
index 463dafd..3d0405d 100644
--- a/src/broadcom/vulkan/v3dv_device.c
+++ b/src/broadcom/vulkan/v3dv_device.c
@@ -610,7 +610,7 @@
.shaderSampledImageArrayDynamicIndexing = false,
.shaderStorageBufferArrayDynamicIndexing = false,
.shaderStorageImageArrayDynamicIndexing = false,
- .shaderClipDistance = false,
+ .shaderClipDistance = true,
.shaderCullDistance = false,
.shaderFloat64 = false,
.shaderInt64 = false,
@@ -784,9 +784,9 @@
.maxSampleMaskWords = 1,
.timestampComputeAndGraphics = false,
.timestampPeriod = 0.0f,
- .maxClipDistances = 0,
+ .maxClipDistances = 8,
.maxCullDistances = 0,
- .maxCombinedClipAndCullDistances = 0,
+ .maxCombinedClipAndCullDistances = 8,
.discreteQueuePriorities = 2,
.pointSizeRange = { 1.0f, 1.0f },
.lineWidthRange = { 1.0f, 32.0f },
diff --git a/src/broadcom/vulkan/v3dv_pipeline.c b/src/broadcom/vulkan/v3dv_pipeline.c
index 491f21e..c735807 100644
--- a/src/broadcom/vulkan/v3dv_pipeline.c
+++ b/src/broadcom/vulkan/v3dv_pipeline.c
@@ -936,7 +936,8 @@
static void
pipeline_populate_v3d_key(struct v3d_key *key,
- const struct v3dv_pipeline_stage *p_stage)
+ const struct v3dv_pipeline_stage *p_stage,
+ uint32_t ucp_enables)
{
/* The following values are default values used at pipeline create, that
* lack the info about the real sampler/texture format used, needed to
@@ -974,11 +975,17 @@
*/
key->is_last_geometry_stage = true;
- /* Vulkan provides a way to define clip distances, but not clip planes, so
- * we understand that this would be always zero. Probably would need to be
- * revisited based on all the clip related extensions available.
+ /* Vulkan doesn't have fixed function state for user clip planes. Instead,
+ * shaders can write to gl_ClipDistance[], in which case the SPIR-V compiler
+ * takes care of adding a single compact array variable at
+ * VARYING_SLOT_CLIP_DIST0, so we don't need any user clip plane lowering.
+ *
+ * The only lowering we are interested is specific to the fragment shader,
+ * where we want to emit discards to honor writes to gl_ClipDistance[] in
+ * previous stages. This is done via nir_lower_clip_fs() so we only set up
+ * the ucp enable mask for that stage.
*/
- key->ucp_enables = 0;
+ key->ucp_enables = ucp_enables;
key->environment = V3D_ENVIRONMENT_VULKAN;
}
@@ -1021,11 +1028,12 @@
static void
pipeline_populate_v3d_fs_key(struct v3d_fs_key *key,
const VkGraphicsPipelineCreateInfo *pCreateInfo,
- const struct v3dv_pipeline_stage *p_stage)
+ const struct v3dv_pipeline_stage *p_stage,
+ uint32_t ucp_enables)
{
memset(key, 0, sizeof(*key));
- pipeline_populate_v3d_key(&key->base, p_stage);
+ pipeline_populate_v3d_key(&key->base, p_stage, ucp_enables);
const VkPipelineInputAssemblyStateCreateInfo *ia_info =
pCreateInfo->pInputAssemblyState;
@@ -1144,7 +1152,7 @@
{
memset(key, 0, sizeof(*key));
- pipeline_populate_v3d_key(&key->base, p_stage);
+ pipeline_populate_v3d_key(&key->base, p_stage, 0);
/* Vulkan doesn't appear to specify (anv does the same) */
key->clamp_color = false;
@@ -1539,6 +1547,26 @@
NIR_PASS_V(p_stage->nir, lower_pipeline_layout_info, pipeline, layout);
}
+/**
+ * The SPIR-V compiler will insert a sized compact array for
+ * VARYING_SLOT_CLIP_DIST0 if the vertex shader writes to gl_ClipDistance[],
+ * where the size of the array determines the number of active clip planes.
+ */
+static uint32_t
+get_ucp_enable_mask(struct v3dv_pipeline_stage **stages)
+{
+ const nir_shader *shader = stages[MESA_SHADER_VERTEX]->nir;
+ assert(shader);
+
+ nir_foreach_variable_with_modes(var, shader, nir_var_shader_out) {
+ if (var->data.location == VARYING_SLOT_CLIP_DIST0) {
+ assert(var->data.compact);
+ return (1 << glsl_get_length(var->type)) - 1;
+ }
+ }
+ return 0;
+}
+
static VkResult
pipeline_compile_graphics(struct v3dv_pipeline *pipeline,
const VkGraphicsPipelineCreateInfo *pCreateInfo,
@@ -1702,7 +1730,8 @@
pipeline->fs = p_stage;
- pipeline_populate_v3d_fs_key(key, pCreateInfo, p_stage);
+ pipeline_populate_v3d_fs_key(key, pCreateInfo, p_stage,
+ get_ucp_enable_mask(stages));
lower_fs_io(p_stage->nir);
@@ -2706,7 +2735,7 @@
struct v3d_key *key = &p_stage->key.base;
memset(key, 0, sizeof(*key));
- pipeline_populate_v3d_key(key, p_stage);
+ pipeline_populate_v3d_key(key, p_stage, 0);
VkResult result;
p_stage->current_variant =
