Added rolling scan line simulation based on the shader subframe featu…

…re. This is implemented with a scrolling scissor rect rather than in the shader itself as this is more efficient although may not work for every shader pass - we may need an option to exclude certain passes. The implementation simply divides the screen up by the number of sub frames and then moves the scissor rect down over the screen over the number of sub frames. (#16282)

config.def.h

@@ -401,6 +401,11 @@
  */
 #define DEFAULT_SHADER_SUBFRAMES 1
 
+/* Divides implements basic rolling scanning of sub frames - does this simply by scrolling a 
+ * a scissor rect down the screen according to how many sub frames there are 
+ */
+#define DEFAULT_SCAN_SUBFRAMES false
+
 /* Inserts black frame(s) inbetween frames.
  * Useful for Higher Hz monitors (set to multiples of 60 Hz) who want to play 60 Hz 
  * material with CRT-like motion clarity.

configuration.c

@@ -1809,6 +1809,8 @@ static struct config_bool_setting *populate_settings_bool(
  /* Let implementation decide if automatic, or 1:1 PAR. */
  SETTING_BOOL("video_aspect_ratio_auto", &settings->bools.video_aspect_ratio_auto, true, DEFAULT_ASPECT_RATIO_AUTO, false);
 
+ SETTING_BOOL("video_scan_subframes", &settings->bools.video_scan_subframes, true, DEFAULT_SCAN_SUBFRAMES, false);
+
  SETTING_BOOL("video_allow_rotate", &settings->bools.video_allow_rotate, true, DEFAULT_ALLOW_ROTATE, false);
  SETTING_BOOL("video_windowed_fullscreen", &settings->bools.video_windowed_fullscreen, true, DEFAULT_WINDOWED_FULLSCREEN, false);
  SETTING_BOOL("video_crop_overscan", &settings->bools.video_crop_overscan, true, DEFAULT_CROP_OVERSCAN, false);

configuration.h

@@ -611,6 +611,7 @@ typedef struct settings
  bool video_shader_watch_files;
  bool video_shader_remember_last_dir;
  bool video_shader_preset_save_reference_enable;
+ bool video_scan_subframes;
  bool video_threaded;
  bool video_font_enable;
  bool video_disable_composition;

gfx/drivers/d3d10.c

@@ -60,6 +60,8 @@
 #error "UWP does not support D3D10"
 #endif
 
+#define D3D10_ROLLING_SCANLINE_SIMULATION
+
 typedef struct
 {
  d3d10_texture_t texture;
@@ -2417,6 +2419,41 @@ static bool d3d10_gfx_frame(
  context->lpVtbl->RSSetViewports(context, 1,
  &d3d10->pass[i].viewport);
 
+#ifdef D3D10_ROLLING_SCANLINE_SIMULATION
+ if ( (video_info->shader_subframes > 1)
+ && (video_info->scan_subframes)
+ && !black_frame_insertion
+ && !nonblock_state
+ && !runloop_is_slowmotion
+ && !runloop_is_paused
+ && (!(d3d10->flags & D3D10_ST_FLAG_MENU_ENABLE)))
+ {
+ D3D10_RECT scissor_rect;
+
+ scissor_rect.left = 0;
+ scissor_rect.top = (unsigned int)(((float)d3d10->pass[i].viewport.Height / (float)video_info->shader_subframes) 
+ * (float)video_info->current_subframe);
+ scissor_rect.right = d3d10->pass[i].viewport.Width ;
+ scissor_rect.bottom = (unsigned int)(((float)d3d10->pass[i].viewport.Height / (float)video_info->shader_subframes) 
+ * (float)(video_info->current_subframe + 1));
+
+ d3d10->device->lpVtbl->RSSetScissorRects(d3d10->device, 1,
+ &scissor_rect);
+ }
+ else
+ {
+ D3D10_RECT scissor_rect;
+
+ scissor_rect.left = 0;
+ scissor_rect.top = 0;
+ scissor_rect.right = d3d10->pass[i].viewport.Width;
+ scissor_rect.bottom = d3d10->pass[i].viewport.Height;
+
+ d3d10->device->lpVtbl->RSSetScissorRects(d3d10->device, 1,
+ &scissor_rect);
+ }
+#endif // D3D10_ROLLING_SCANLINE_SIMULATION 
+
  context->lpVtbl->Draw(context, 4, 0);
  texture = &d3d10->pass[i].rt;
  }
@@ -2448,6 +2485,29 @@ static bool d3d10_gfx_frame(
  d3d10->clearcolor);
  context->lpVtbl->RSSetViewports(context, 1, &d3d10->frame.viewport);
 
+#ifdef D3D10_ROLLING_SCANLINE_SIMULATION 
+ if ( (video_info->shader_subframes > 1)
+ && (video_info->scan_subframes)
+ && !black_frame_insertion
+ && !nonblock_state
+ && !runloop_is_slowmotion
+ && !runloop_is_paused
+ && (!(d3d10->flags & D3D10_ST_FLAG_MENU_ENABLE)))
+ {
+ D3D10_RECT scissor_rect;
+
+ scissor_rect.left = 0;
+ scissor_rect.top = (unsigned int)(((float)video_height / (float)video_info->shader_subframes) 
+ * (float)video_info->current_subframe);
+ scissor_rect.right = video_width ;
+ scissor_rect.bottom = (unsigned int)(((float)video_height / (float)video_info->shader_subframes) 
+ * (float)(video_info->current_subframe + 1));
+
+ d3d10->device->lpVtbl->RSSetScissorRects(d3d10->device, 1,
+ &scissor_rect);
+ }
+ else
+#endif // D3D10_ROLLING_SCANLINE_SIMULATION 
  {
  D3D10_RECT scissor_rect;
 
@@ -2464,6 +2524,20 @@ static bool d3d10_gfx_frame(
  context->lpVtbl->OMSetBlendState(context, d3d10->blend_enable, NULL,
  D3D10_DEFAULT_SAMPLE_MASK);
 
+#ifdef D3D10_ROLLING_SCANLINE_SIMULATION 
+ {
+ D3D10_RECT scissor_rect;
+
+ scissor_rect.left = 0;
+ scissor_rect.top = 0;
+ scissor_rect.right = video_width;
+ scissor_rect.bottom = video_height;
+
+ d3d10->device->lpVtbl->RSSetScissorRects(d3d10->device, 1,
+ &scissor_rect);
+ }
+#endif // D3D10_ROLLING_SCANLINE_SIMULATION 
+
  if ( (d3d10->flags & D3D10_ST_FLAG_MENU_ENABLE)
  && d3d10->menu.texture.handle)
  {
@@ -2622,8 +2696,13 @@ static bool d3d10_gfx_frame(
  && (!(d3d10->flags & D3D10_ST_FLAG_FRAME_DUPE_LOCK)))
  {
  d3d10->flags |= D3D10_ST_FLAG_FRAME_DUPE_LOCK;
+
  for (k = 1; k < video_info->shader_subframes; k++)
  {
+#ifdef D3D10_ROLLING_SCANLINE_SIMULATION 
+ video_info->current_subframe = k;
+#endif // D3D10_ROLLING_SCANLINE_SIMULATION 
+
  if (d3d10->shader_preset)
  for (m = 0; m < d3d10->shader_preset->passes; m++)
  {

gfx/drivers/d3d11.c

@@ -76,6 +76,8 @@ const GUID DECLSPEC_SELECTANY libretro_IID_IDXGIFactory5 = { 0x7632e1f5,0xee65,0
 #endif
 #endif
 
+#define D3D11_ROLLING_SCANLINE_SIMULATION
+
 /* Temporary workaround for d3d11 not being able to poll flags during init */
 static gfx_ctx_driver_t d3d11_fake_context;
 
@@ -3025,7 +3027,23 @@ static bool d3d11_gfx_frame(
  context, width, height, pitch, d3d11->format, frame, &d3d11->frame.texture[0]);
  }
 
- context->lpVtbl->RSSetState(context, d3d11->scissor_disabled);
+#ifdef D3D11_ROLLING_SCANLINE_SIMULATION 
+ if ( (video_info->shader_subframes > 1)
+ && (video_info->scan_subframes)
+ && !black_frame_insertion
+ && !nonblock_state
+ && !runloop_is_slowmotion
+ && !runloop_is_paused
+ && (!(d3d11->flags & D3D11_ST_FLAG_MENU_ENABLE)))
+ {
+ context->lpVtbl->RSSetState(context, d3d11->scissor_enabled);
+ }
+ else
+#endif // D3D11_ROLLING_SCANLINE_SIMULATION 
+ {
+ context->lpVtbl->RSSetState(context, d3d11->scissor_disabled);
+ } 
+
  d3d11->context->lpVtbl->OMSetBlendState(
  d3d11->context, d3d11->blend_disable,
  NULL, D3D11_DEFAULT_SAMPLE_MASK);
@@ -3158,6 +3176,41 @@ static bool d3d11_gfx_frame(
  &d3d11->pass[i].rt.rt_view, NULL);
  context->lpVtbl->RSSetViewports(context, 1, &d3d11->pass[i].viewport);
 
+#ifdef D3D11_ROLLING_SCANLINE_SIMULATION 
+ if ( (video_info->shader_subframes > 1)
+ && (video_info->scan_subframes)
+ && !black_frame_insertion
+ && !nonblock_state
+ && !runloop_is_slowmotion
+ && !runloop_is_paused
+ && (!(d3d11->flags & D3D11_ST_FLAG_MENU_ENABLE)))
+ {
+ D3D11_RECT scissor_rect;
+
+ scissor_rect.left = 0;
+ scissor_rect.top = (unsigned int)(((float)d3d11->pass[i].viewport.Height / (float)video_info->shader_subframes) 
+ * (float)video_info->current_subframe);
+ scissor_rect.right = d3d11->pass[i].viewport.Width ;
+ scissor_rect.bottom = (unsigned int)(((float)d3d11->pass[i].viewport.Height / (float)video_info->shader_subframes) 
+ * (float)(video_info->current_subframe + 1));
+
+ d3d11->context->lpVtbl->RSSetScissorRects(d3d11->context, 1,
+ &scissor_rect);
+ }
+ else
+ {
+ D3D11_RECT scissor_rect;
+
+ scissor_rect.left = 0;
+ scissor_rect.top = 0;
+ scissor_rect.right = d3d11->pass[i].viewport.Width;
+ scissor_rect.bottom = d3d11->pass[i].viewport.Height;
+
+ d3d11->context->lpVtbl->RSSetScissorRects(d3d11->context, 1,
+ &scissor_rect);
+ }
+#endif // D3D11_ROLLING_SCANLINE_SIMULATION 
+
  if (i == d3d11->shader_preset->passes - 1)
  context->lpVtbl->Draw(context, 4, 0);
  else
@@ -3204,6 +3257,33 @@ static bool d3d11_gfx_frame(
  context->lpVtbl->VSSetConstantBuffers(context, 0, 1, &d3d11->frame.ubo);
  }
 
+#ifdef D3D11_ROLLING_SCANLINE_SIMULATION 
+ if ( (video_info->shader_subframes > 1)
+ && (video_info->scan_subframes)
+ && !black_frame_insertion
+ && !nonblock_state
+ && !runloop_is_slowmotion
+ && !runloop_is_paused
+ && (!(d3d11->flags & D3D11_ST_FLAG_MENU_ENABLE)))
+ {
+ D3D11_RECT scissor_rect;
+
+ scissor_rect.left = 0;
+ scissor_rect.top = (unsigned int)(((float)video_height / (float)video_info->shader_subframes) 
+ * (float)video_info->current_subframe);
+ scissor_rect.right = video_width ;
+ scissor_rect.bottom = (unsigned int)(((float)video_height / (float)video_info->shader_subframes) 
+ * (float)(video_info->current_subframe + 1));
+
+ d3d11->context->lpVtbl->RSSetScissorRects(d3d11->context, 1,
+ &scissor_rect);
+ }
+ else
+ {
+ d3d11->context->lpVtbl->RSSetScissorRects(d3d11->context, 1, &d3d11->scissor);
+ }
+#endif // D3D11_ROLLING_SCANLINE_SIMULATION 
+
  context->lpVtbl->Draw(context, 4, 0);
  context->lpVtbl->RSSetState(context, d3d11->scissor_enabled);
  d3d11->context->lpVtbl->RSSetScissorRects(d3d11->context, 1, &d3d11->scissor);
@@ -3458,6 +3538,10 @@ static bool d3d11_gfx_frame(
  d3d11->flags |= D3D11_ST_FLAG_FRAME_DUPE_LOCK;
  for (k = 1; k < video_info->shader_subframes; k++)
  {
+#ifdef D3D11_ROLLING_SCANLINE_SIMULATION 
+ video_info->current_subframe = k;
+#endif // D3D11_ROLLING_SCANLINE_SIMULATION 
+
  if (d3d11->shader_preset)
  for (m = 0; m < d3d11->shader_preset->passes; m++)
  {

gfx/drivers/d3d12.c

@@ -79,6 +79,8 @@
  } \
 }
 
+#define D3D12_ROLLING_SCANLINE_SIMULATION
+
 typedef struct
 {
  d3d12_texture_t texture;
@@ -3748,8 +3750,33 @@ static bool d3d12_gfx_frame(
 #endif
  cmd->lpVtbl->RSSetViewports(cmd, 1,
  &d3d12->pass[i].viewport);
- cmd->lpVtbl->RSSetScissorRects(cmd, 1,
- &d3d12->pass[i].scissorRect);
+
+#ifdef D3D12_ROLLING_SCANLINE_SIMULATION 
+ if ( (video_info->shader_subframes > 1)
+ && (video_info->scan_subframes)
+ && !black_frame_insertion
+ && !nonblock_state
+ && !runloop_is_slowmotion
+ && !runloop_is_paused
+ && (!(d3d12->flags & D3D12_ST_FLAG_MENU_ENABLE)))
+ {
+ D3D12_RECT scissor_rect;
+
+ scissor_rect.left = 0;
+ scissor_rect.top = (unsigned int)(((float)d3d12->pass[i].viewport.Height / (float)video_info->shader_subframes) 
+ * (float)video_info->current_subframe);
+ scissor_rect.right = d3d12->pass[i].viewport.Width;
+ scissor_rect.bottom = (unsigned int)(((float)d3d12->pass[i].viewport.Height / (float)video_info->shader_subframes) 
+ * (float)(video_info->current_subframe + 1));
+
+ cmd->lpVtbl->RSSetScissorRects(cmd, 1, &scissor_rect);
+ }
+ else
+#endif // D3D12_ROLLING_SCANLINE_SIMULATION 
+ {
+ cmd->lpVtbl->RSSetScissorRects(cmd, 1, 
+ &d3d12->pass[i].scissorRect);
+ } 
 
  if (i == d3d12->shader_preset->passes - 1)
  start_vertex_location = 0;
@@ -3836,7 +3863,32 @@ static bool d3d12_gfx_frame(
  }
 
  cmd->lpVtbl->RSSetViewports(cmd, 1, &d3d12->frame.viewport);
- cmd->lpVtbl->RSSetScissorRects(cmd, 1, &d3d12->frame.scissorRect);
+
+#ifdef D3D12_ROLLING_SCANLINE_SIMULATION 
+ if ( (video_info->shader_subframes > 1)
+ && (video_info->scan_subframes)
+ && !black_frame_insertion
+ && !nonblock_state
+ && !runloop_is_slowmotion
+ && !runloop_is_paused
+ && (!(d3d12->flags & D3D12_ST_FLAG_MENU_ENABLE)))
+ {
+ D3D12_RECT scissor_rect;
+
+ scissor_rect.left = 0;
+ scissor_rect.top = (unsigned int)(((float)video_height / (float)video_info->shader_subframes) 
+ * (float)video_info->current_subframe);
+ scissor_rect.right = video_width ;
+ scissor_rect.bottom = (unsigned int)(((float)video_height / (float)video_info->shader_subframes) 
+ * (float)(video_info->current_subframe + 1));
+
+ cmd->lpVtbl->RSSetScissorRects(cmd, 1, &scissor_rect);
+ }
+ else
+#endif // D3D12_ROLLING_SCANLINE_SIMULATION 
+ {
+ cmd->lpVtbl->RSSetScissorRects(cmd, 1, &d3d12->frame.scissorRect);
+ } 
 
  cmd->lpVtbl->DrawInstanced(cmd, 4, 1, 0, 0);
 
@@ -4046,6 +4098,10 @@ static bool d3d12_gfx_frame(
  d3d12->flags |= D3D12_ST_FLAG_FRAME_DUPE_LOCK;
  for (k = 1; k < video_info->shader_subframes; k++)
  {
+#ifdef D3D12_ROLLING_SCANLINE_SIMULATION 
+ video_info->current_subframe = k;
+#endif // D3D12_ROLLING_SCANLINE_SIMULATION 
+
  if (d3d12->shader_preset)
  for (m = 0; m < d3d12->shader_preset->passes; m++)
  {

gfx/drivers/gl3.c

@@ -2604,6 +2604,25 @@ static bool gl3_frame(void *data, const void *frame,
  gl->filter_chain, 1);
  }
 
+#ifdef GL3_ROLLING_SCANLINE_SIMULATION 
+ if ( (video_info->shader_subframes > 1)
+ && (video_info->scan_subframes)
+ && !video_info->black_frame_insertion
+ && !video_info->input_driver_nonblock_state
+ && !video_info->runloop_is_slowmotion
+ && !video_info->runloop_is_paused
+ && (!(gl->flags & GL3_FLAG_MENU_TEXTURE_ENABLE)))
+ {
+ gl3_filter_chain_set_simulate_scanline(
+ gl->filter_chain, true);
+ }
+ else
+ {
+ gl3_filter_chain_set_simulate_scanline(
+ gl->filter_chain, false);
+ } 
+#endif // GL3_ROLLING_SCANLINE_SIMULATION 
+
  gl3_filter_chain_set_input_texture(gl->filter_chain, &texture);
  gl3_filter_chain_build_offscreen_passes(gl->filter_chain,
  &gl->filter_chain_vp);