gstreamer/subprojects/gst-plugins-bad/sys/d3d11/gstd3d11overlaycompositor.cpp

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/* GStreamer
* Copyright (C) <2019> Seungha Yang <seungha.yang@navercorp.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "gstd3d11overlaycompositor.h"
#include "gstd3d11pluginutils.h"
#include <wrl.h>
#include <memory>
#include <vector>
#include <algorithm>
GST_DEBUG_CATEGORY_EXTERN (gst_d3d11_overlay_compositor_debug);
#define GST_CAT_DEFAULT gst_d3d11_overlay_compositor_debug
/* *INDENT-OFF* */
using namespace Microsoft::WRL;
typedef struct
{
struct {
FLOAT x;
FLOAT y;
FLOAT z;
} position;
struct {
FLOAT u;
FLOAT v;
} texture;
} VertexData;
struct GstD3D11CompositionOverlay
{
~GstD3D11CompositionOverlay ()
{
if (overlay_rect)
gst_video_overlay_rectangle_unref (overlay_rect);
if (d3d11_buffer)
gst_buffer_unref (d3d11_buffer);
}
GstVideoOverlayRectangle *overlay_rect = nullptr;
ComPtr<ID3D11Texture2D> texture;
ComPtr<ID3D11ShaderResourceView> srv;
ComPtr<ID3D11Buffer> vertex_buffer;
gboolean premul_alpha = FALSE;
GstBuffer *d3d11_buffer = nullptr;
};
typedef std::shared_ptr<GstD3D11CompositionOverlay> GstD3D11CompositionOverlayPtr;
struct _GstD3D11OverlayCompositorPrivate
{
GstVideoInfo info;
D3D11_VIEWPORT viewport;
ComPtr<ID3D11PixelShader> ps;
ComPtr<ID3D11PixelShader> premul_ps;
ComPtr<ID3D11VertexShader> vs;
ComPtr<ID3D11InputLayout> layout;
ComPtr<ID3D11SamplerState> sampler;
ComPtr<ID3D11BlendState> blend;
ComPtr<ID3D11Buffer> index_buffer;
ComPtr<ID3D11RasterizerState> rs;
std::vector<GstVideoOverlayRectangle *> rects_to_upload;
std::vector<GstD3D11CompositionOverlayPtr> overlays;
};
/* *INDENT-ON* */
static void gst_d3d11_overlay_compositor_finalize (GObject * object);
#define gst_d3d11_overlay_compositor_parent_class parent_class
G_DEFINE_TYPE (GstD3D11OverlayCompositor,
gst_d3d11_overlay_compositor, GST_TYPE_OBJECT);
static void
gst_d3d11_overlay_compositor_class_init (GstD3D11OverlayCompositorClass * klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
object_class->finalize = gst_d3d11_overlay_compositor_finalize;
}
static void
gst_d3d11_overlay_compositor_init (GstD3D11OverlayCompositor * self)
{
self->priv = new GstD3D11OverlayCompositorPrivate ();
}
static void
gst_d3d11_overlay_compositor_finalize (GObject * object)
{
GstD3D11OverlayCompositor *self = GST_D3D11_OVERLAY_COMPOSITOR (object);
delete self->priv;
gst_clear_object (&self->device);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static GstD3D11CompositionOverlayPtr
gst_d3d11_composition_overlay_new (GstD3D11OverlayCompositor * self,
GstVideoOverlayRectangle * overlay_rect)
{
GstD3D11OverlayCompositorPrivate *priv = self->priv;
gint x, y;
guint width, height;
D3D11_SUBRESOURCE_DATA subresource_data;
D3D11_TEXTURE2D_DESC texture_desc;
D3D11_SHADER_RESOURCE_VIEW_DESC srv_desc;
D3D11_BUFFER_DESC buffer_desc;
D3D11_MAPPED_SUBRESOURCE map;
VertexData *vertex_data;
GstBuffer *buf;
GstVideoMeta *vmeta;
GstMapInfo info;
guint8 *data;
gint stride;
HRESULT hr;
ID3D11Device *device_handle;
ID3D11DeviceContext *context_handle;
GstD3D11Device *device = self->device;
FLOAT x1, y1, x2, y2;
gdouble val;
ComPtr < ID3D11Texture2D > texture;
ComPtr < ID3D11ShaderResourceView > srv;
ComPtr < ID3D11Buffer > vertex_buffer;
GstVideoOverlayFormatFlags flags;
gboolean premul_alpha = FALSE;
GstMemory *mem;
gboolean is_d3d11 = FALSE;
memset (&subresource_data, 0, sizeof (subresource_data));
memset (&texture_desc, 0, sizeof (texture_desc));
memset (&srv_desc, 0, sizeof (srv_desc));
memset (&buffer_desc, 0, sizeof (buffer_desc));
device_handle = gst_d3d11_device_get_device_handle (device);
context_handle = gst_d3d11_device_get_device_context_handle (device);
if (!gst_video_overlay_rectangle_get_render_rectangle (overlay_rect, &x, &y,
&width, &height)) {
GST_ERROR_OBJECT (self, "Failed to get render rectangle");
return nullptr;
}
flags = gst_video_overlay_rectangle_get_flags (overlay_rect);
if ((flags & GST_VIDEO_OVERLAY_FORMAT_FLAG_PREMULTIPLIED_ALPHA) != 0) {
premul_alpha = TRUE;
flags = GST_VIDEO_OVERLAY_FORMAT_FLAG_PREMULTIPLIED_ALPHA;
} else {
flags = GST_VIDEO_OVERLAY_FORMAT_FLAG_NONE;
}
buf = gst_video_overlay_rectangle_get_pixels_unscaled_argb (overlay_rect,
flags);
if (!buf) {
GST_ERROR_OBJECT (self, "Failed to get overlay buffer");
return nullptr;
}
mem = gst_buffer_peek_memory (buf, 0);
if (gst_is_d3d11_memory (mem)) {
GstD3D11Memory *dmem = GST_D3D11_MEMORY_CAST (mem);
if (dmem->device == self->device) {
srv = gst_d3d11_memory_get_shader_resource_view (dmem, 0);
if (srv) {
texture = (ID3D11Texture2D *)
gst_d3d11_memory_get_resource_handle (dmem);
is_d3d11 = TRUE;
}
}
}
if (!is_d3d11) {
vmeta = gst_buffer_get_video_meta (buf);
if (!vmeta) {
GST_ERROR_OBJECT (self, "Failed to get video meta");
return nullptr;
}
if (!gst_video_meta_map (vmeta,
0, &info, (gpointer *) & data, &stride, GST_MAP_READ)) {
GST_ERROR_OBJECT (self, "Failed to map");
return nullptr;
}
/* Do create texture and upload data at once, for create immutable texture */
subresource_data.pSysMem = data;
subresource_data.SysMemPitch = stride;
subresource_data.SysMemSlicePitch = 0;
texture_desc.Width = vmeta->width;
texture_desc.Height = vmeta->height;
texture_desc.MipLevels = 1;
texture_desc.ArraySize = 1;
texture_desc.Format = DXGI_FORMAT_B8G8R8A8_UNORM;
texture_desc.SampleDesc.Count = 1;
texture_desc.SampleDesc.Quality = 0;
texture_desc.Usage = D3D11_USAGE_IMMUTABLE;
texture_desc.BindFlags = D3D11_BIND_SHADER_RESOURCE;
texture_desc.CPUAccessFlags = 0;
hr = device_handle->CreateTexture2D (&texture_desc,
&subresource_data, &texture);
gst_video_meta_unmap (vmeta, 0, &info);
if (!gst_d3d11_result (hr, device)) {
GST_ERROR_OBJECT (self, "Failed to create texture");
return nullptr;
}
srv_desc.ViewDimension = D3D11_SRV_DIMENSION_TEXTURE2D;
srv_desc.Texture2D.MipLevels = 1;
hr = device_handle->CreateShaderResourceView (texture.Get (), &srv_desc,
&srv);
if (!gst_d3d11_result (hr, device) || !srv) {
GST_ERROR_OBJECT (self, "Failed to create shader resource view");
return nullptr;
}
}
buffer_desc.Usage = D3D11_USAGE_DYNAMIC;
buffer_desc.ByteWidth = sizeof (VertexData) * 4;
buffer_desc.BindFlags = D3D11_BIND_VERTEX_BUFFER;
buffer_desc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
hr = device_handle->CreateBuffer (&buffer_desc, nullptr, &vertex_buffer);
if (!gst_d3d11_result (hr, device)) {
GST_ERROR_OBJECT (self,
"Couldn't create vertex buffer, hr: 0x%x", (guint) hr);
return nullptr;
}
GstD3D11DeviceLockGuard lk (device);
hr = context_handle->Map (vertex_buffer.Get (),
0, D3D11_MAP_WRITE_DISCARD, 0, &map);
if (!gst_d3d11_result (hr, device)) {
GST_ERROR_OBJECT (self, "Couldn't map vertex buffer, hr: 0x%x", (guint) hr);
return nullptr;
}
vertex_data = (VertexData *) map.pData;
/* bottom left */
gst_util_fraction_to_double (x, GST_VIDEO_INFO_WIDTH (&priv->info), &val);
x1 = (val * 2.0f) - 1.0f;
gst_util_fraction_to_double (y + height,
GST_VIDEO_INFO_HEIGHT (&priv->info), &val);
y1 = (val * -2.0f) + 1.0f;
/* top right */
gst_util_fraction_to_double (x + width,
GST_VIDEO_INFO_WIDTH (&priv->info), &val);
x2 = (val * 2.0f) - 1.0f;
gst_util_fraction_to_double (y, GST_VIDEO_INFO_HEIGHT (&priv->info), &val);
y2 = (val * -2.0f) + 1.0f;
/* bottom left */
vertex_data[0].position.x = x1;
vertex_data[0].position.y = y1;
vertex_data[0].position.z = 0.0f;
vertex_data[0].texture.u = 0.0f;
vertex_data[0].texture.v = 1.0f;
/* top left */
vertex_data[1].position.x = x1;
vertex_data[1].position.y = y2;
vertex_data[1].position.z = 0.0f;
vertex_data[1].texture.u = 0.0f;
vertex_data[1].texture.v = 0.0f;
/* top right */
vertex_data[2].position.x = x2;
vertex_data[2].position.y = y2;
vertex_data[2].position.z = 0.0f;
vertex_data[2].texture.u = 1.0f;
vertex_data[2].texture.v = 0.0f;
/* bottom right */
vertex_data[3].position.x = x2;
vertex_data[3].position.y = y1;
vertex_data[3].position.z = 0.0f;
vertex_data[3].texture.u = 1.0f;
vertex_data[3].texture.v = 1.0f;
context_handle->Unmap (vertex_buffer.Get (), 0);
auto overlay = std::make_shared < GstD3D11CompositionOverlay > ();
overlay->overlay_rect = gst_video_overlay_rectangle_ref (overlay_rect);
overlay->texture = texture;
overlay->srv = srv;
overlay->vertex_buffer = vertex_buffer;
overlay->premul_alpha = premul_alpha;
if (is_d3d11)
overlay->d3d11_buffer = gst_buffer_ref (buf);
return overlay;
}
static gboolean
gst_d3d11_overlay_compositor_setup_shader (GstD3D11OverlayCompositor * self)
{
GstD3D11OverlayCompositorPrivate *priv = self->priv;
GstVideoInfo *info = &priv->info;
GstD3D11Device *device = self->device;
HRESULT hr;
D3D11_BUFFER_DESC buffer_desc;
D3D11_BLEND_DESC blend_desc;
D3D11_MAPPED_SUBRESOURCE map;
WORD *indices;
ID3D11Device *device_handle;
ID3D11DeviceContext *context_handle;
ComPtr < ID3D11PixelShader > ps;
ComPtr < ID3D11PixelShader > premul_ps;
ComPtr < ID3D11VertexShader > vs;
ComPtr < ID3D11InputLayout > layout;
ComPtr < ID3D11SamplerState > sampler;
ComPtr < ID3D11BlendState > blend;
ComPtr < ID3D11Buffer > index_buffer;
ComPtr < ID3D11RasterizerState > rs;
memset (&buffer_desc, 0, sizeof (buffer_desc));
memset (&blend_desc, 0, sizeof (blend_desc));
device_handle = gst_d3d11_device_get_device_handle (device);
context_handle = gst_d3d11_device_get_device_context_handle (device);
hr = gst_d3d11_device_get_sampler (device,
D3D11_FILTER_MIN_MAG_LINEAR_MIP_POINT, &sampler);
if (!gst_d3d11_result (hr, device)) {
GST_ERROR_OBJECT (self, "Couldn't create sampler state, hr: 0x%x",
(guint) hr);
return FALSE;
}
hr = gst_d3d11_get_pixel_shader_sample (device, &ps);
if (!gst_d3d11_result (hr, device)) {
GST_ERROR_OBJECT (self, "Couldn't create pixel shader");
return FALSE;
}
hr = gst_d3d11_get_pixel_shader_sample_premul (device, &premul_ps);
if (!gst_d3d11_result (hr, device)) {
GST_ERROR_OBJECT (self, "Couldn't create premul pixel shader");
return FALSE;
}
hr = gst_d3d11_get_vertex_shader_coord (device, &vs, &layout);
if (!gst_d3d11_result (hr, device)) {
GST_ERROR_OBJECT (self, "Couldn't create vertex pixel shader");
return FALSE;
}
hr = gst_d3d11_device_get_rasterizer (device, &rs);
if (!gst_d3d11_result (hr, device)) {
GST_ERROR_OBJECT (self, "Couldn't get rasterizer state");
return FALSE;
}
blend_desc.AlphaToCoverageEnable = FALSE;
blend_desc.IndependentBlendEnable = FALSE;
blend_desc.RenderTarget[0].BlendEnable = TRUE;
blend_desc.RenderTarget[0].SrcBlend = D3D11_BLEND_ONE;
blend_desc.RenderTarget[0].DestBlend = D3D11_BLEND_INV_SRC_ALPHA;
blend_desc.RenderTarget[0].BlendOp = D3D11_BLEND_OP_ADD;
blend_desc.RenderTarget[0].SrcBlendAlpha = D3D11_BLEND_ONE;
blend_desc.RenderTarget[0].DestBlendAlpha = D3D11_BLEND_INV_SRC_ALPHA;
blend_desc.RenderTarget[0].BlendOpAlpha = D3D11_BLEND_OP_ADD;
blend_desc.RenderTarget[0].RenderTargetWriteMask =
D3D11_COLOR_WRITE_ENABLE_ALL;
hr = device_handle->CreateBlendState (&blend_desc, &blend);
if (!gst_d3d11_result (hr, device)) {
GST_ERROR_OBJECT (self,
"Couldn't create blend staten, hr: 0x%x", (guint) hr);
return FALSE;
}
buffer_desc.Usage = D3D11_USAGE_DYNAMIC;
buffer_desc.ByteWidth = sizeof (WORD) * 6;
buffer_desc.BindFlags = D3D11_BIND_INDEX_BUFFER;
buffer_desc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
hr = device_handle->CreateBuffer (&buffer_desc, nullptr, &index_buffer);
if (!gst_d3d11_result (hr, device)) {
GST_ERROR_OBJECT (self,
"Couldn't create index buffer, hr: 0x%x", (guint) hr);
return FALSE;
}
GstD3D11DeviceLockGuard lk (device);
hr = context_handle->Map (index_buffer.Get (),
0, D3D11_MAP_WRITE_DISCARD, 0, &map);
if (!gst_d3d11_result (hr, device)) {
GST_ERROR_OBJECT (self, "Couldn't map index buffer, hr: 0x%x", (guint) hr);
return FALSE;
}
indices = (WORD *) map.pData;
/* clockwise indexing */
indices[0] = 0; /* bottom left */
indices[1] = 1; /* top left */
indices[2] = 2; /* top right */
indices[3] = 3; /* bottom right */
indices[4] = 0; /* bottom left */
indices[5] = 2; /* top right */
context_handle->Unmap (index_buffer.Get (), 0);
priv->ps = ps;
priv->premul_ps = premul_ps;
priv->vs = vs;
priv->layout = layout;
priv->sampler = sampler;
priv->blend = blend;
priv->index_buffer = index_buffer;
priv->rs = rs;
priv->viewport.TopLeftX = 0;
priv->viewport.TopLeftY = 0;
priv->viewport.Width = GST_VIDEO_INFO_WIDTH (info);
priv->viewport.Height = GST_VIDEO_INFO_HEIGHT (info);
priv->viewport.MinDepth = 0.0f;
priv->viewport.MaxDepth = 1.0f;
return TRUE;
}
GstD3D11OverlayCompositor *
gst_d3d11_overlay_compositor_new (GstD3D11Device * device,
const GstVideoInfo * info)
{
GstD3D11OverlayCompositor *self = nullptr;
GstD3D11OverlayCompositorPrivate *priv;
g_return_val_if_fail (GST_IS_D3D11_DEVICE (device), nullptr);
g_return_val_if_fail (info != nullptr, nullptr);
self = (GstD3D11OverlayCompositor *)
g_object_new (GST_TYPE_D3D11_OVERLAY_COMPOSITOR, nullptr);
gst_object_ref_sink (self);
priv = self->priv;
self->device = (GstD3D11Device *) gst_object_ref (device);
priv->info = *info;
if (!gst_d3d11_overlay_compositor_setup_shader (self)) {
gst_object_unref (self);
return nullptr;
}
return self;
}
static gboolean
gst_d3d11_overlay_compositor_foreach_meta (GstBuffer * buffer, GstMeta ** meta,
GstD3D11OverlayCompositor * self)
{
GstD3D11OverlayCompositorPrivate *priv = self->priv;
GstVideoOverlayCompositionMeta *cmeta;
guint num_rect;
if ((*meta)->info->api != GST_VIDEO_OVERLAY_COMPOSITION_META_API_TYPE)
return TRUE;
cmeta = (GstVideoOverlayCompositionMeta *) (*meta);
if (!cmeta->overlay)
return TRUE;
num_rect = gst_video_overlay_composition_n_rectangles (cmeta->overlay);
for (guint i = 0; i < num_rect; i++) {
auto rect = gst_video_overlay_composition_get_rectangle (cmeta->overlay, i);
priv->rects_to_upload.push_back (rect);
}
return TRUE;
}
gboolean
gst_d3d11_overlay_compositor_upload (GstD3D11OverlayCompositor * compositor,
GstBuffer * buf)
{
GstD3D11OverlayCompositorPrivate *priv;
g_return_val_if_fail (compositor != nullptr, FALSE);
g_return_val_if_fail (GST_IS_BUFFER (buf), FALSE);
priv = compositor->priv;
priv->rects_to_upload.clear ();
gst_buffer_foreach_meta (buf,
(GstBufferForeachMetaFunc) gst_d3d11_overlay_compositor_foreach_meta,
compositor);
if (priv->rects_to_upload.empty ()) {
priv->overlays.clear ();
return TRUE;
}
GST_LOG_OBJECT (compositor, "Found %" G_GSIZE_FORMAT
" overlay rectangles, %" G_GSIZE_FORMAT " in current queue",
priv->rects_to_upload.size (), priv->overlays.size ());
/* *INDENT-OFF* */
for (auto it : priv->rects_to_upload) {
if (std::find_if (priv->overlays.begin (), priv->overlays.end (),
[&] (const auto & overlay) -> bool {
return overlay->overlay_rect == it;
}) == priv->overlays.end ()) {
auto new_overlay = gst_d3d11_composition_overlay_new (compositor, it);
if (!new_overlay)
return FALSE;
priv->overlays.push_back (new_overlay);
}
}
/* *INDENT-ON* */
GST_LOG_OBJECT (compositor, "Overlay rectangles in queue after uploaded %"
G_GSIZE_FORMAT, priv->overlays.size ());
/* Remove old overlay */
/* *INDENT-OFF* */
auto it = priv->overlays.begin ();
while (it != priv->overlays.end ()) {
auto old_overlay = *it;
if (std::find_if (priv->rects_to_upload.begin (),
priv->rects_to_upload.end (), [&] (const auto & overlay) -> bool {
return overlay == old_overlay->overlay_rect;
}) == priv->rects_to_upload.end ()) {
GST_LOG_OBJECT (compositor, "Removing %p from queue",
old_overlay->overlay_rect);
it = priv->overlays.erase (it);
} else {
it++;
}
}
/* *INDENT-ON* */
GST_LOG_OBJECT (compositor, "Final queue size %" G_GSIZE_FORMAT,
priv->overlays.size ());
return TRUE;
}
gboolean
gst_d3d11_overlay_compositor_update_viewport (GstD3D11OverlayCompositor *
compositor, D3D11_VIEWPORT * viewport)
{
g_return_val_if_fail (GST_IS_D3D11_OVERLAY_COMPOSITOR (compositor), FALSE);
g_return_val_if_fail (viewport != nullptr, FALSE);
compositor->priv->viewport = *viewport;
return TRUE;
}
gboolean
gst_d3d11_overlay_compositor_draw (GstD3D11OverlayCompositor * compositor,
ID3D11RenderTargetView * rtv[GST_VIDEO_MAX_PLANES])
{
g_return_val_if_fail (compositor != nullptr, FALSE);
g_return_val_if_fail (rtv != nullptr, FALSE);
GstD3D11DeviceLockGuard lk (compositor->device);
return gst_d3d11_overlay_compositor_draw_unlocked (compositor, rtv);
}
gboolean
gst_d3d11_overlay_compositor_draw_unlocked (GstD3D11OverlayCompositor *
compositor, ID3D11RenderTargetView * rtv[GST_VIDEO_MAX_PLANES])
{
GstD3D11OverlayCompositorPrivate *priv;
ID3D11DeviceContext *context;
ID3D11ShaderResourceView *clear_view[GST_VIDEO_MAX_PLANES] = { nullptr, };
UINT strides = sizeof (VertexData);
UINT offsets = 0;
ID3D11SamplerState *samplers[1];
g_return_val_if_fail (compositor != nullptr, FALSE);
g_return_val_if_fail (rtv != nullptr, FALSE);
priv = compositor->priv;
if (priv->overlays.empty ())
return TRUE;
samplers[0] = priv->sampler.Get ();
context = gst_d3d11_device_get_device_context_handle (compositor->device);
context->IASetPrimitiveTopology (D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
context->IASetInputLayout (priv->layout.Get ());
context->IASetIndexBuffer (priv->index_buffer.Get (),
DXGI_FORMAT_R16_UINT, 0);
context->PSSetSamplers (0, 1, samplers);
context->VSSetShader (priv->vs.Get (), nullptr, 0);
context->RSSetViewports (1, &priv->viewport);
context->RSSetState (priv->rs.Get ());
context->OMSetRenderTargets (1, rtv, nullptr);
context->OMSetBlendState (priv->blend.Get (), nullptr, 0xffffffff);
/* *INDENT-OFF* */
for (auto overlay : priv->overlays) {
ID3D11ShaderResourceView *srv[] = { overlay->srv.Get () };
ID3D11Buffer *vertex_buf[] = { overlay->vertex_buffer.Get () };
GstMapInfo info;
GstMemory *mem = nullptr;
if (overlay->d3d11_buffer) {
mem = gst_buffer_peek_memory (overlay->d3d11_buffer, 0);
gst_memory_map (mem, &info, (GstMapFlags) (GST_MAP_D3D11 | GST_MAP_READ));
}
if (!overlay->premul_alpha)
context->PSSetShader (priv->premul_ps.Get (), nullptr, 0);
else
context->PSSetShader (priv->ps.Get (), nullptr, 0);
context->PSSetShaderResources (0, 1, srv);
context->IASetVertexBuffers (0, 1, vertex_buf, &strides, &offsets);
context->DrawIndexed (6, 0, 0);
if (mem)
gst_memory_unmap (mem, &info);
}
/* *INDENT-ON* */
context->PSSetShaderResources (0, 1, clear_view);
context->OMSetRenderTargets (0, nullptr, nullptr);
return TRUE;
}