From 778ffadd54c2fd93261a1b3e133124b9aadfdc00 Mon Sep 17 00:00:00 2001
From: Bill Currie <bill@taniwha.org>
Date: Sat, 20 Jan 2024 19:42:28 +0900
Subject: [PATCH] [vulkan] Implement fog for the forward renderer

Other than decoupled lightmap support, I think that has the vulkan
forward renderer feature complete (though a little buggy with its
lightmap updates and fisheye gets validation errors).
---
 libs/video/renderer/Makemodule.am               | 13 +++++++------
 libs/video/renderer/vulkan/rp_main_fwd.plist    |  1 +
 libs/video/renderer/vulkan/shader/bsp_sky.frag  | 14 +++-----------
 libs/video/renderer/vulkan/shader/bsp_turb.frag | 17 ++++-------------
 libs/video/renderer/vulkan/shader/fog.finc      | 11 +++++++++++
 libs/video/renderer/vulkan/shader/particle.frag | 10 +++++++++-
 .../video/renderer/vulkan/shader/qskin_fwd.frag |  5 ++++-
 libs/video/renderer/vulkan/shader/quakebsp.frag | 15 ++++-----------
 libs/video/renderer/vulkan/shader/sprite.frag   |  5 ++++-
 libs/video/renderer/vulkan/vulkan_alias.c       |  2 ++
 libs/video/renderer/vulkan/vulkan_bsp.c         |  5 ++---
 libs/video/renderer/vulkan/vulkan_iqm.c         |  2 ++
 libs/video/renderer/vulkan/vulkan_particles.c   |  4 +++-
 libs/video/renderer/vulkan/vulkan_sprite.c      |  4 ++++
 14 files changed, 60 insertions(+), 48 deletions(-)
 create mode 100644 libs/video/renderer/vulkan/shader/fog.finc

diff --git a/libs/video/renderer/Makemodule.am b/libs/video/renderer/Makemodule.am
index 291d3b887..09334bf81 100644
--- a/libs/video/renderer/Makemodule.am
+++ b/libs/video/renderer/Makemodule.am
@@ -367,6 +367,7 @@ composef_c = $(vkshaderpath)/compose.frag.spvc
 compose_fwdf_src = $(vkshaderpath)/compose_fwd.frag
 compose_fwdf_c = $(vkshaderpath)/compose_fwd.frag.spvc
 infplane = $(vkshaderpath)/infplane.finc
+fog_h = $(vkshaderpath)/fog.finc
 oit_blend = $(vkshaderpath)/oit_blend.finc
 oit_store = $(vkshaderpath)/oit_store.finc
 oit_h = $(vkshaderpath)/oit.h
@@ -416,9 +417,9 @@ $(partphysicsc_c): $(partphysicsc_src)
 $(partupdatec_c): $(partupdatec_src)
 $(particlev_c): $(particlev_src) $(matrices_h)
 $(particleg_c): $(particleg_src) $(matrices_h)
-$(particlef_c): $(particlef_src) $(oit_store) $(oit_h)
+$(particlef_c): $(particlef_src) $(oit_store) $(oit_h) $(fog_h)
 
-$(spritef_c): $(spritef_src)
+$(spritef_c): $(spritef_src) $(fog_h)
 
 $(sprite_gbufv_c): $(sprite_gbufv_src) $(matrices_h)
 
@@ -436,7 +437,7 @@ $(twodf_c): $(twodf_src)
 
 $(quakebspv_c): $(quakebspv_src) $(entity_h) $(matrices_h)
 
-$(quakebspf_c): $(quakebspf_src)
+$(quakebspf_c): $(quakebspf_src) $(fog_h)
 
 $(bsp_depth_c): $(bsp_depth_src) $(entity_h) $(matrices_h)
 
@@ -448,9 +449,9 @@ $(bsp_gbuff_c): $(bsp_gbuff_src)
 
 $(bsp_shadow_c): $(bsp_shadow_src) $(entity_h)
 
-$(bsp_skyf_c): $(bsp_skyf_src) $(oit_store) $(oit_h)
+$(bsp_skyf_c): $(bsp_skyf_src) $(oit_store) $(oit_h) $(fog_h)
 
-$(bsp_turbf_c): $(bsp_turbf_src) $(oit_store) $(oit_h)
+$(bsp_turbf_c): $(bsp_turbf_src) $(oit_store) $(oit_h) $(fog_h)
 
 $(debug_c): $(debug_src) $(lighting_h)
 
@@ -484,7 +485,7 @@ $(aliasv_c): $(aliasv_src) $(matrices_h)
 
 $(alias_depth_c): $(alias_depth_src) $(matrices_h)
 
-$(qskin_fwdf_c): $(qskin_fwdf_src)
+$(qskin_fwdf_c): $(qskin_fwdf_src) $(fog_h)
 
 $(qskin_gbuf_c): $(qskin_gbuf_src)
 
diff --git a/libs/video/renderer/vulkan/rp_main_fwd.plist b/libs/video/renderer/vulkan/rp_main_fwd.plist
index f6799f035..b9fc87264 100644
--- a/libs/video/renderer/vulkan/rp_main_fwd.plist
+++ b/libs/video/renderer/vulkan/rp_main_fwd.plist
@@ -496,6 +496,7 @@ properties = {
 				descriptorSets = (matrix_set, texture_set, oit_set);
 				pushConstants = {
 					vertex = { Model = mat4; };
+					fragment = { fog = vec4; };
 				};
 			};
 			physics = {
diff --git a/libs/video/renderer/vulkan/shader/bsp_sky.frag b/libs/video/renderer/vulkan/shader/bsp_sky.frag
index a574bec37..f9c90edd8 100644
--- a/libs/video/renderer/vulkan/shader/bsp_sky.frag
+++ b/libs/video/renderer/vulkan/shader/bsp_sky.frag
@@ -2,6 +2,8 @@
 #extension GL_GOOGLE_include_directive : enable
 #extension GL_EXT_multiview : enable
 
+#include "fog.finc"
+
 #include "oit_store.finc"
 
 layout (constant_id = 0) const bool doSkyBox = false;
@@ -26,16 +28,6 @@ layout(early_fragment_tests) in;
 
 const float SCALE = 189.0 / 64.0;
 
-vec4
-fogBlend (vec4 color)
-{
-	float       az = fog.a * gl_FragCoord.z / gl_FragCoord.w;
-	vec3        fog_color = fog.rgb;
-	float       fog_factor = exp (-az * az);
-
-	return vec4 (mix (fog_color.rgb, color.rgb, fog_factor), color.a);
-}
-
 vec4
 sky_sheet (vec3 dir, float time)
 {
@@ -100,6 +92,6 @@ main (void)
 	} else {
 		c = vec4 (0, 0, 0, 1);
 	}
-	//frag_color = c;//fogBlend (c);
+	c = FogBlend (c, fog);
 	StoreFrag (c, gl_FragCoord.z);
 }
diff --git a/libs/video/renderer/vulkan/shader/bsp_turb.frag b/libs/video/renderer/vulkan/shader/bsp_turb.frag
index 7254eee87..6f454748c 100644
--- a/libs/video/renderer/vulkan/shader/bsp_turb.frag
+++ b/libs/video/renderer/vulkan/shader/bsp_turb.frag
@@ -2,6 +2,8 @@
 #extension GL_GOOGLE_include_directive : enable
 #extension GL_EXT_multiview : enable
 
+#include "fog.finc"
+
 #include "oit_store.finc"
 
 layout (set = 3, binding = 0) uniform sampler2DArray Texture;
@@ -18,7 +20,6 @@ layout (location = 1) in vec3 direction;
 layout (location = 2) in vec4 color;
 
 layout(early_fragment_tests) in;
-//layout (location = 0) out vec4 frag_color;
 
 const float PI = 3.14159265;
 const float SPEED = 20.0;
@@ -35,16 +36,6 @@ warp_st (vec2 st, float time)
 	return st + turb_scale * (sin ((angle + phase) * FACTOR) + BIAS) / SCALE;
 }
 
-vec4
-fogBlend (vec4 color)
-{
-	float       az = fog.a * gl_FragCoord.z / gl_FragCoord.w;
-	vec3        fog_color = fog.rgb;
-	float       fog_factor = exp (-az * az);
-
-	return vec4 (mix (fog_color.rgb, color.rgb, fog_factor), color.a);
-}
-
 void
 main (void)
 {
@@ -54,6 +45,6 @@ main (void)
 	float       a = c.a * e.a * alpha;
 	c += e;
 	c.a = a;
-	//frag_color = c * color;//fogBlend (c);
-	StoreFrag (c * color, gl_FragCoord.z);
+	c = FogBlend (c * color, fog);
+	StoreFrag (c, gl_FragCoord.z);
 }
diff --git a/libs/video/renderer/vulkan/shader/fog.finc b/libs/video/renderer/vulkan/shader/fog.finc
new file mode 100644
index 000000000..af572a27b
--- /dev/null
+++ b/libs/video/renderer/vulkan/shader/fog.finc
@@ -0,0 +1,11 @@
+vec4
+FogBlend (vec4 color, vec4 fog)
+{
+	float       az = fog.a * 1 / gl_FragCoord.w;
+	//float       az = fog.a * (4 - gl_FragCoord.w);
+	vec4        fog_color = vec4 (fog.rgb, 1.0);
+
+	float fog_factor = exp (-az * az);
+	//return vec4 (mix (fog_color.rgb, color.rgb, fog_factor), color.a);
+	return mix (fog_color, color, fog_factor);
+}
diff --git a/libs/video/renderer/vulkan/shader/particle.frag b/libs/video/renderer/vulkan/shader/particle.frag
index 304f07d2d..55bc15b85 100644
--- a/libs/video/renderer/vulkan/shader/particle.frag
+++ b/libs/video/renderer/vulkan/shader/particle.frag
@@ -2,8 +2,15 @@
 #extension GL_GOOGLE_include_directive : enable
 #extension GL_EXT_multiview : enable
 
+#include "fog.finc"
+
 #include "oit_store.finc"
 
+layout (push_constant) uniform PushConstants {
+	layout (offset = 64)
+	vec4        fog;
+};
+
 layout (location = 0) in vec4 uv_tr;
 layout (location = 1) in vec4 color;
 
@@ -19,6 +26,7 @@ main (void)
 	if (a <= 0) {
 		discard;
 	}
-	c *= (a);
+	//c = c * a;
+	c = FogBlend (c * a, fog);
 	StoreFrag (c, gl_FragCoord.z);
 }
diff --git a/libs/video/renderer/vulkan/shader/qskin_fwd.frag b/libs/video/renderer/vulkan/shader/qskin_fwd.frag
index b9b75cbfd..d61e1ab62 100644
--- a/libs/video/renderer/vulkan/shader/qskin_fwd.frag
+++ b/libs/video/renderer/vulkan/shader/qskin_fwd.frag
@@ -1,4 +1,7 @@
 #version 450
+#extension GL_GOOGLE_include_directive : enable
+
+#include "fog.finc"
 
 layout (set = 1, binding = 0) uniform sampler2D Palette;
 layout (set = 2, binding = 0) uniform sampler2DArray Skin;
@@ -35,5 +38,5 @@ main (void)
 	light -= d * shadelight;
 	light = max (light, 0.0) / 255;
 
-	frag_color = light * c + e;//fogBlend (c);
+	frag_color = FogBlend (light * c + e, fog);
 }
diff --git a/libs/video/renderer/vulkan/shader/quakebsp.frag b/libs/video/renderer/vulkan/shader/quakebsp.frag
index 32942539e..eb83e7991 100644
--- a/libs/video/renderer/vulkan/shader/quakebsp.frag
+++ b/libs/video/renderer/vulkan/shader/quakebsp.frag
@@ -1,4 +1,7 @@
 #version 450
+#extension GL_GOOGLE_include_directive : enable
+
+#include "fog.finc"
 
 layout (set = 3, binding = 0) uniform sampler2DArray Texture;
 layout (set = 4, binding = 0) uniform sampler2D Lightmap;
@@ -17,16 +20,6 @@ layout (location = 4) in vec4 color;
 
 layout (location = 0) out vec4 frag_color;
 
-vec4
-fogBlend (vec4 color)
-{
-	float       az = fog.a * gl_FragCoord.z / gl_FragCoord.w;
-	vec3        fog_color = fog.rgb;
-	float       fog_factor = exp (-az * az);
-
-	return vec4 (mix (fog_color.rgb, color.rgb, fog_factor), color.a);
-}
-
 void
 main (void)
 {
@@ -38,5 +31,5 @@ main (void)
 	vec4        e = texture (Texture, e_st);
 	vec4        l = texture (Lightmap, l_st);
 
-	frag_color = c * l + e;//fogBlend (c);
+	frag_color = FogBlend (c * l + e, fog);
 }
diff --git a/libs/video/renderer/vulkan/shader/sprite.frag b/libs/video/renderer/vulkan/shader/sprite.frag
index 50bddebab..7a8a9fb28 100644
--- a/libs/video/renderer/vulkan/shader/sprite.frag
+++ b/libs/video/renderer/vulkan/shader/sprite.frag
@@ -1,4 +1,7 @@
 #version 450
+#extension GL_GOOGLE_include_directive : enable
+
+#include "fog.finc"
 
 layout (set = 1, binding = 1) uniform sampler2DArray Texture;
 
@@ -27,5 +30,5 @@ main (void)
 	if (pix.a < 0.5) {
 		discard;
 	}
-	frag_color = pix;
+	frag_color = FogBlend (pix, fog);
 }
diff --git a/libs/video/renderer/vulkan/vulkan_alias.c b/libs/video/renderer/vulkan/vulkan_alias.c
index edca4594a..76a085386 100644
--- a/libs/video/renderer/vulkan/vulkan_alias.c
+++ b/libs/video/renderer/vulkan/vulkan_alias.c
@@ -122,6 +122,7 @@ push_alias_constants (const mat4f_t mat, float blend, byte *colors,
 		.blend = blend,
 		.colors = { VEC4_EXP (colors) },
 		.base_color = base_color,
+		.fog = Fog_Get (),
 	};
 
 	qfv_push_constants_t push_constants[] = {
@@ -161,6 +162,7 @@ push_fwd_constants (const mat4f_t mat, float blend, byte *colors,
 		.shadelight = lighting->shadelight,
 		.lightvec = { VectorExpand (lighting->lightvec) },
 		.base_color = base_color,
+		.fog = Fog_Get (),
 	};
 
 	qfv_push_constants_t push_constants[] = {
diff --git a/libs/video/renderer/vulkan/vulkan_bsp.c b/libs/video/renderer/vulkan/vulkan_bsp.c
index 62abf2355..7f6c89728 100644
--- a/libs/video/renderer/vulkan/vulkan_bsp.c
+++ b/libs/video/renderer/vulkan/vulkan_bsp.c
@@ -77,7 +77,7 @@
 #define LIGHTMAP_SET 4
 
 typedef struct bsp_push_constants_s {
-	quat_t      fog;
+	vec4f_t     fog;
 	float       time;
 	float       alpha;
 	float       turb_scale;
@@ -862,9 +862,8 @@ static void
 push_fragconst (QFV_BspQueue queue, VkPipelineLayout layout,
 				qfv_device_t *device, VkCommandBuffer cmd)
 {
-	//XXX glsl_Fog_GetColor (fog);
-	//XXX fog[3] = glsl_Fog_GetDensity () / 64.0;
 	bsp_frag_constants_t constants = {
+		.fog = Fog_Get (),
 		.time = vr_data.realtime,
 		.alpha = queue == QFV_bspTurb ? r_wateralpha : 1,
 		.turb_scale = queue == QFV_bspTurb ? 1 : 0,
diff --git a/libs/video/renderer/vulkan/vulkan_iqm.c b/libs/video/renderer/vulkan/vulkan_iqm.c
index b685f0123..3a82576f9 100644
--- a/libs/video/renderer/vulkan/vulkan_iqm.c
+++ b/libs/video/renderer/vulkan/vulkan_iqm.c
@@ -213,6 +213,7 @@ push_iqm_constants (const mat4f_t mat, float blend, byte *colors,
 		.blend = blend,
 		.colors = { VEC4_EXP (colors) },
 		.base_color = base_color,
+		.fog = Fog_Get (),
 	};
 
 	qfv_push_constants_t push_constants[] = {
@@ -252,6 +253,7 @@ push_fwd_constants (const mat4f_t mat, float blend, byte *colors,
 		.shadelight = lighting->shadelight,
 		.lightvec = { VectorExpand (lighting->lightvec) },
 		.base_color = base_color,
+		.fog = Fog_Get (),
 	};
 
 	qfv_push_constants_t push_constants[] = {
diff --git a/libs/video/renderer/vulkan/vulkan_particles.c b/libs/video/renderer/vulkan/vulkan_particles.c
index 830ac58d1..d8e26c53a 100644
--- a/libs/video/renderer/vulkan/vulkan_particles.c
+++ b/libs/video/renderer/vulkan/vulkan_particles.c
@@ -182,10 +182,12 @@ particles_draw (const exprval_t **params, exprval_t *result, exprctx_t *ectx)
 
 	mat4f_t     mat;
 	mat4fidentity (mat);
+	vec4f_t     fog = Fog_Get ();
 	qfv_push_constants_t push_constants[] = {
 		{ VK_SHADER_STAGE_VERTEX_BIT, 0, sizeof (mat4f_t), &mat },
+		{ VK_SHADER_STAGE_FRAGMENT_BIT, 64, sizeof (fog), &fog },
 	};
-	QFV_PushConstants (device, cmd, layout, 1, push_constants);
+	QFV_PushConstants (device, cmd, layout, 2, push_constants);
 	VkDeviceSize offsets[] = { 0 };
 	VkBuffer    buffers[] = {
 		pframe->states,
diff --git a/libs/video/renderer/vulkan/vulkan_sprite.c b/libs/video/renderer/vulkan/vulkan_sprite.c
index 3984df75f..38e9b391a 100644
--- a/libs/video/renderer/vulkan/vulkan_sprite.c
+++ b/libs/video/renderer/vulkan/vulkan_sprite.c
@@ -156,10 +156,14 @@ sprite_draw_ent (qfv_taskctx_t *taskctx, entity_t ent)
 
 	mat4f_t     mat = {};
 	uint32_t    frame;
+	vec4f_t     fog = Fog_Get ();
 	qfv_push_constants_t push_constants[] = {
 		{ VK_SHADER_STAGE_VERTEX_BIT, 0, sizeof (mat), mat },
 		{ VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT,
 			64, sizeof (frame), &frame },
+		{ VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT,
+			64, sizeof (frame), &frame },
+		{ VK_SHADER_STAGE_FRAGMENT_BIT, 72, sizeof (fog), &fog },
 	};
 
 	auto animation = Entity_GetAnimation (ent);