anv: implement EXT_depth_clip_control

A new extension allowing the application to use the OpenGL depth
range in NDC, i.e. with depth in range [-1, 1], as opposed to
Vulkan’s default of [0, 1].

v2:
- call gfx8_cmd_buffer_emit_viewport on ANV_CMD_DIRTY_PIPELINE (Jason)
- remove redundant !! operator since negativeOneToOne must be true or
  false (Tapani)
- coding style changes (Lionel)

Gitlab: https://gitlab.freedesktop.org/mesa/mesa/-/issues/6070
Signed-off-by: Vadym Shovkoplias <vadym.shovkoplias@globallogic.com>
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15304>

src/intel/vulkan/anv_device.c

@@ -256,6 +256,7 @@ get_device_extensions(const struct anv_physical_device *device,
       .EXT_conditional_rendering             = device->info.verx10 >= 75,
       .EXT_conservative_rasterization        = device->info.ver >= 9,
       .EXT_custom_border_color               = device->info.ver >= 8,
+      .EXT_depth_clip_control                = true,
       .EXT_depth_clip_enable                 = true,
       .EXT_descriptor_indexing               = device->has_a64_buffer_access &&
                                                device->has_bindless_images,
@@ -1783,6 +1784,13 @@ void anv_GetPhysicalDeviceFeatures2(
          break;
       }
 
+      case VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_DEPTH_CLIP_CONTROL_FEATURES_EXT: {
+         VkPhysicalDeviceDepthClipControlFeaturesEXT *features =
+            (VkPhysicalDeviceDepthClipControlFeaturesEXT *)ext;
+         features->depthClipControl = true;
+         break;
+      }
+
       default:
          anv_debug_ignored_stype(ext->sType);
          break;

src/intel/vulkan/anv_pipeline.c

@@ -2142,6 +2142,13 @@ copy_non_dynamic_state(struct anv_graphics_pipeline *pipeline,
    if (!raster_discard) {
       assert(pCreateInfo->pViewportState);
 
+      const VkPipelineViewportDepthClipControlCreateInfoEXT *ccontrol =
+         vk_find_struct_const(pCreateInfo->pViewportState,
+                              PIPELINE_VIEWPORT_DEPTH_CLIP_CONTROL_CREATE_INFO_EXT);
+
+      if (ccontrol)
+         pipeline->negative_one_to_one = ccontrol->negativeOneToOne;
+
       dynamic->viewport.count = pCreateInfo->pViewportState->viewportCount;
       if (states & ANV_CMD_DIRTY_DYNAMIC_VIEWPORT) {
          typed_memcpy(dynamic->viewport.viewports,
@@ -2571,7 +2578,8 @@ anv_graphics_pipeline_init(struct anv_graphics_pipeline *pipeline,
    const VkPipelineRasterizationDepthClipStateCreateInfoEXT *clip_info =
       vk_find_struct_const(pCreateInfo->pRasterizationState->pNext,
                            PIPELINE_RASTERIZATION_DEPTH_CLIP_STATE_CREATE_INFO_EXT);
-   pipeline->depth_clip_enable = clip_info ? clip_info->depthClipEnable : !pipeline->depth_clamp_enable;
+   pipeline->depth_clip_enable = clip_info ? clip_info->depthClipEnable :
+      !(pipeline->depth_clamp_enable || pipeline->negative_one_to_one);
 
    result = anv_pipeline_compile_graphics(pipeline, cache, pCreateInfo);
    if (result != VK_SUCCESS) {

src/intel/vulkan/anv_private.h

@@ -3528,6 +3528,7 @@ struct anv_graphics_pipeline {
    bool                                         kill_pixel;
    bool                                         depth_bounds_test_enable;
    bool                                         force_fragment_thread_dispatch;
+   bool                                         negative_one_to_one;
 
    /* When primitive replication is used, subpass->view_mask will describe what
     * views to replicate.

src/intel/vulkan/genX_cmd_buffer.c

@@ -3949,11 +3949,9 @@ genX(cmd_buffer_flush_state)(struct anv_cmd_buffer *cmd_buffer)
          cmd_buffer_emit_streamout(cmd_buffer);
    }
 
-   if (cmd_buffer->state.gfx.dirty & ANV_CMD_DIRTY_DYNAMIC_VIEWPORT)
-      gfx8_cmd_buffer_emit_viewport(cmd_buffer);
-
    if (cmd_buffer->state.gfx.dirty & (ANV_CMD_DIRTY_DYNAMIC_VIEWPORT |
                                   ANV_CMD_DIRTY_PIPELINE)) {
+      gfx8_cmd_buffer_emit_viewport(cmd_buffer);
       gfx8_cmd_buffer_emit_depth_viewport(cmd_buffer,
                                           pipeline->depth_clamp_enable);
    }

src/intel/vulkan/gfx8_cmd_buffer.c

@@ -44,6 +44,11 @@ gfx8_cmd_buffer_emit_viewport(struct anv_cmd_buffer *cmd_buffer)
    struct anv_state sf_clip_state =
       anv_cmd_buffer_alloc_dynamic_state(cmd_buffer, count * 64, 64);
 
+   bool negative_one_to_one =
+      cmd_buffer->state.gfx.pipeline->negative_one_to_one;
+
+   float scale = negative_one_to_one ? 0.5f : 1.0f;
+
    for (uint32_t i = 0; i < count; i++) {
       const VkViewport *vp = &viewports[i];
 
@@ -52,10 +57,11 @@ gfx8_cmd_buffer_emit_viewport(struct anv_cmd_buffer *cmd_buffer)
       struct GENX(SF_CLIP_VIEWPORT) sfv = {
          .ViewportMatrixElementm00 = vp->width / 2,
          .ViewportMatrixElementm11 = vp->height / 2,
-         .ViewportMatrixElementm22 = vp->maxDepth - vp->minDepth,
+         .ViewportMatrixElementm22 = (vp->maxDepth - vp->minDepth) * scale,
          .ViewportMatrixElementm30 = vp->x + vp->width / 2,
          .ViewportMatrixElementm31 = vp->y + vp->height / 2,
-         .ViewportMatrixElementm32 = vp->minDepth,
+         .ViewportMatrixElementm32 = negative_one_to_one ?
+            (vp->minDepth + vp->maxDepth) * scale : vp->minDepth,
          .XMinClipGuardband = -1.0f,
          .XMaxClipGuardband = 1.0f,
          .YMinClipGuardband = -1.0f,