Major update to the HDR system of RetroArch (#18616)

* Major update to the HDR system of RetroArch

* Fix compilation error in SPIRV enabled versions of d3d12

* Fixed incorrect comment syntax for linux builds etc

Author: MajorPainTheCactus

config.def.h

@@ -505,11 +505,14 @@
 /* The number of nits that paper white is at */
 #define DEFAULT_VIDEO_HDR_PAPER_WHITE_NITS 200.0f
 
-/* The contrast setting for hdr used to calculate the display gamma by dividing this value by gamma 2.2  */
-#define DEFAULT_VIDEO_HDR_CONTRAST 5.0f
-
 /* Should we expand the colour gamut when using hdr */
-#define DEFAULT_VIDEO_HDR_EXPAND_GAMUT true
+#define DEFAULT_VIDEO_HDR_EXPAND_GAMUT false
+
+/* Enable a basic HDR scanline implementation which is the main reason for using HDR in RetroArch */
+#define DEFAULT_VIDEO_HDR_SCANLINES true
+
+/* Default to the largely standard RGB layout */
+#define DEFAULT_VIDEO_HDR_SUBPIXEL_LAYOUT 0
 
 /* When presets are saved they will be saved using the #reference
  * directive by default */

configuration.c

@@ -1919,6 +1919,7 @@ static struct config_bool_setting *populate_settings_bool(
    SETTING_BOOL("video_fullscreen",              &settings->bools.video_fullscreen, true, DEFAULT_FULLSCREEN, false);
    SETTING_BOOL("video_hdr_enable",              &settings->bools.video_hdr_enable, true, DEFAULT_VIDEO_HDR_ENABLE, false);
    SETTING_BOOL("video_hdr_expand_gamut",        &settings->bools.video_hdr_expand_gamut, true, DEFAULT_VIDEO_HDR_EXPAND_GAMUT, false);
+   SETTING_BOOL("video_hdr_scanlines",           &settings->bools.video_hdr_scanlines, true, DEFAULT_VIDEO_HDR_SCANLINES, false);
    SETTING_BOOL("video_vsync",                   &settings->bools.video_vsync, true, DEFAULT_VSYNC, false);
    SETTING_BOOL("video_adaptive_vsync",          &settings->bools.video_adaptive_vsync, true, DEFAULT_ADAPTIVE_VSYNC, false);
    SETTING_BOOL("video_hard_sync",               &settings->bools.video_hard_sync, true, DEFAULT_HARD_SYNC, false);
@@ -2366,7 +2367,6 @@ static struct config_float_setting *populate_settings_float(
    SETTING_FLOAT("video_msg_bgcolor_opacity",    &settings->floats.video_msg_bgcolor_opacity, true, DEFAULT_MESSAGE_BGCOLOR_OPACITY, false);
    SETTING_FLOAT("video_hdr_max_nits",           &settings->floats.video_hdr_max_nits, true, DEFAULT_VIDEO_HDR_MAX_NITS, false);
    SETTING_FLOAT("video_hdr_paper_white_nits",   &settings->floats.video_hdr_paper_white_nits, true, DEFAULT_VIDEO_HDR_PAPER_WHITE_NITS, false);
-   SETTING_FLOAT("video_hdr_display_contrast",   &settings->floats.video_hdr_display_contrast, true, DEFAULT_VIDEO_HDR_CONTRAST, false);
 
    SETTING_FLOAT("input_axis_threshold",         &settings->floats.input_axis_threshold,     true, DEFAULT_AXIS_THRESHOLD, false);
    SETTING_FLOAT("input_analog_deadzone",        &settings->floats.input_analog_deadzone,    true, DEFAULT_ANALOG_DEADZONE, false);
@@ -2558,6 +2558,7 @@ static struct config_uint_setting *populate_settings_uint(
    SETTING_UINT("video_record_scale_factor",     &settings->uints.video_record_scale_factor, true, 1, false);
    SETTING_UINT("video_stream_scale_factor",     &settings->uints.video_stream_scale_factor, true, 1, false);
 
+   SETTING_UINT("video_hdr_subpixel_layout",    &settings->uints.video_hdr_subpixel_layout, true, DEFAULT_VIDEO_HDR_SUBPIXEL_LAYOUT, false);
 #ifdef HAVE_NETWORKING
    SETTING_UINT("streaming_mode",                &settings->uints.streaming_mode, true, STREAMING_MODE_TWITCH, false);
 #endif

configuration.h

@@ -382,6 +382,8 @@ typedef struct settings
       unsigned video_bfi_dark_frames;
       unsigned video_shader_subframes;
       unsigned video_autoswitch_refresh_rate;
+      unsigned video_hdr_subpixel_layout;
+
       unsigned quit_on_close_content;
 
 #ifdef HAVE_LAKKA
@@ -426,7 +428,6 @@ typedef struct settings
       float video_msg_bgcolor_opacity;
       float video_hdr_max_nits;
       float video_hdr_paper_white_nits;
-      float video_hdr_display_contrast;
 
       float menu_scale_factor;
       float menu_widget_scale_factor;
@@ -688,6 +689,7 @@ typedef struct settings
       bool video_notch_write_over_enable;
       bool video_hdr_enable;
       bool video_hdr_expand_gamut;
+      bool video_hdr_scanlines;
       bool video_use_metal_arg_buffers;
 
       /* Accessibility */

gfx/common/dxgi_common.h

@@ -24,12 +24,23 @@ RETRO_BEGIN_DECLS
 typedef struct ALIGN(16)
 {
    math_matrix_4x4   mvp;
-   float             contrast;         /* 2.0f    */
-   float             paper_white_nits; /* 200.0f  */
-   float             max_nits;         /* 1000.0f */
-   float             expand_gamut;     /* 1.0f    */
-   float             inverse_tonemap;  /* 1.0f    */
-   float             hdr10;            /* 1.0f    */
+   struct
+   {
+      float width;
+      float height;
+   } source_size;
+   struct
+   {
+      float width;
+      float height;
+   } output_size;
+   float             paper_white_nits;    /* 200.0f  */
+   float             max_nits;            /* 1000.0f */
+   unsigned          subpixel_layout;     /* 0       */
+   float             scanlines;           /* 1.0f    */
+   float             expand_gamut;        /* 0.0f    */
+   float             inverse_tonemap;     /* 1.0f    */
+   float             hdr10;               /* 1.0f    */
 } dxgi_hdr_uniform_t;
 
 enum dxgi_swapchain_bit_depth

gfx/common/vulkan_common.h

@@ -31,8 +31,6 @@
 
 #define VULKAN_DIRTY_DYNAMIC_BIT                0x0001
 
-#define VULKAN_HDR_SWAPCHAIN
-
 #include "vksym.h"
 
 #include <boolean.h>

gfx/drivers/caca_gfx.c

@@ -418,8 +418,9 @@ static const video_poke_interface_t caca_poke_interface = {
    NULL, /* get_hw_render_interface */
    NULL, /* set_hdr_max_nits */
    NULL, /* set_hdr_paper_white_nits */
-   NULL, /* set_hdr_contrast */
-   NULL  /* set_hdr_expand_gamut */
+   NULL, /* set_hdr_expand_gamut */
+   NULL, /* set_hdr_scanlines */
+   NULL  /* set_hdr_subpixel_layout */
 };
 
 static void caca_get_poke_interface(void *data,

gfx/drivers/ctr_gfx.c

@@ -2988,8 +2988,9 @@ static const video_poke_interface_t ctr_poke_interface = {
    NULL, /* get_hw_render_interface */
    NULL, /* set_hdr_max_nits */
    NULL, /* set_hdr_paper_white_nits */
-   NULL, /* set_hdr_contrast */
-   NULL  /* set_hdr_expand_gamut */
+   NULL, /* set_hdr_expand_gamut */
+   NULL, /* set_hdr_scanlines */
+   NULL  /* set_hdr_subpixel_layout */
 };
 
 static void ctr_get_poke_interface(void* data,

gfx/drivers/d3d10.c

@@ -3276,8 +3276,9 @@ static const video_poke_interface_t d3d10_poke_interface = {
 #endif
    NULL, /* set_hdr_max_nits */
    NULL, /* set_hdr_paper_white_nits */
-   NULL, /* set_hdr_contrast */
-   NULL  /* set_hdr_expand_gamut */
+   NULL, /* set_hdr_expand_gamut */
+   NULL, /* set_hdr_scanlines */
+   NULL  /* set_hdr_subpixel_layout */
 };
 
 static void d3d10_gfx_get_poke_interface(void* data, const video_poke_interface_t** iface)