Add API to control shadow intensity from the game/mod (#11944)

* Also Disable shadows when sun/moon is hidden. Fixes #11972.

4 files changed, 146 insertions, 136 deletions

diff --git a/client/shaders/nodes_shader/opengl_fragment.glsl b/client/shaders/nodes_shader/opengl_fragment.glsl
index e5f5c703a..adc8adccb 100644
--- a/client/shaders/nodes_shader/opengl_fragment.glsl
+++ b/client/shaders/nodes_shader/opengl_fragment.glsl
@@ -16,6 +16,7 @@ uniform float animationTimer;
 	uniform float f_textureresolution;
 	uniform mat4 m_ShadowViewProj;
 	uniform float f_shadowfar;
+	uniform float f_shadow_strength;
 	varying float normalOffsetScale;
 	varying float adj_shadow_strength;
 	varying float cosLight;
@@ -483,55 +484,57 @@ void main(void)
 	vec4 col = vec4(color.rgb * varColor.rgb, 1.0);
 
 #ifdef ENABLE_DYNAMIC_SHADOWS
-	float shadow_int = 0.0;
-	vec3 shadow_color = vec3(0.0, 0.0, 0.0);
-	vec3 posLightSpace = getLightSpacePosition();
+	if (f_shadow_strength > 0.0) {
+		float shadow_int = 0.0;
+		vec3 shadow_color = vec3(0.0, 0.0, 0.0);
+		vec3 posLightSpace = getLightSpacePosition();
 
-	float distance_rate = (1 - pow(clamp(2.0 * length(posLightSpace.xy - 0.5),0.0,1.0), 20.0));
-	float f_adj_shadow_strength = max(adj_shadow_strength-mtsmoothstep(0.9,1.1,  posLightSpace.z  ),0.0);
+		float distance_rate = (1 - pow(clamp(2.0 * length(posLightSpace.xy - 0.5),0.0,1.0), 20.0));
+		float f_adj_shadow_strength = max(adj_shadow_strength-mtsmoothstep(0.9,1.1,  posLightSpace.z  ),0.0);
 
-	if (distance_rate > 1e-7) {
-	
+		if (distance_rate > 1e-7) {
+		
 #ifdef COLORED_SHADOWS
-		vec4 visibility;
-		if (cosLight > 0.0)
-			visibility = getShadowColor(ShadowMapSampler, posLightSpace.xy, posLightSpace.z);
-		else
-			visibility = vec4(1.0, 0.0, 0.0, 0.0);
-		shadow_int = visibility.r;
-		shadow_color = visibility.gba;
+			vec4 visibility;
+			if (cosLight > 0.0)
+				visibility = getShadowColor(ShadowMapSampler, posLightSpace.xy, posLightSpace.z);
+			else
+				visibility = vec4(1.0, 0.0, 0.0, 0.0);
+			shadow_int = visibility.r;
+			shadow_color = visibility.gba;
 #else
-		if (cosLight > 0.0)
-			shadow_int = getShadow(ShadowMapSampler, posLightSpace.xy, posLightSpace.z);
-		else
-			shadow_int = 1.0;
+			if (cosLight > 0.0)
+				shadow_int = getShadow(ShadowMapSampler, posLightSpace.xy, posLightSpace.z);
+			else
+				shadow_int = 1.0;
 #endif
-		shadow_int *= distance_rate;
-		shadow_int = clamp(shadow_int, 0.0, 1.0);
+			shadow_int *= distance_rate;
+			shadow_int = clamp(shadow_int, 0.0, 1.0);
 
-	}
+		}
 
-	// turns out that nightRatio falls off much faster than
-	// actual brightness of artificial light in relation to natual light.
-	// Power ratio was measured on torches in MTG (brightness = 14).
-	float adjusted_night_ratio = pow(max(0.0, nightRatio), 0.6);
-
-	// Apply self-shadowing when light falls at a narrow angle to the surface
-	// Cosine of the cut-off angle.
-	const float self_shadow_cutoff_cosine = 0.035;
-	if (f_normal_length != 0 && cosLight < self_shadow_cutoff_cosine) {
-		shadow_int = max(shadow_int, 1 - clamp(cosLight, 0.0, self_shadow_cutoff_cosine)/self_shadow_cutoff_cosine);
-		shadow_color = mix(vec3(0.0), shadow_color, min(cosLight, self_shadow_cutoff_cosine)/self_shadow_cutoff_cosine);
-	}
+		// turns out that nightRatio falls off much faster than
+		// actual brightness of artificial light in relation to natual light.
+		// Power ratio was measured on torches in MTG (brightness = 14).
+		float adjusted_night_ratio = pow(max(0.0, nightRatio), 0.6);
+
+		// Apply self-shadowing when light falls at a narrow angle to the surface
+		// Cosine of the cut-off angle.
+		const float self_shadow_cutoff_cosine = 0.035;
+		if (f_normal_length != 0 && cosLight < self_shadow_cutoff_cosine) {
+			shadow_int = max(shadow_int, 1 - clamp(cosLight, 0.0, self_shadow_cutoff_cosine)/self_shadow_cutoff_cosine);
+			shadow_color = mix(vec3(0.0), shadow_color, min(cosLight, self_shadow_cutoff_cosine)/self_shadow_cutoff_cosine);
+		}
 
-	shadow_int *= f_adj_shadow_strength;
-	
-	// calculate fragment color from components:
-	col.rgb =
-			adjusted_night_ratio * col.rgb + // artificial light
-			(1.0 - adjusted_night_ratio) * ( // natural light
-					col.rgb * (1.0 - shadow_int * (1.0 - shadow_color)) +  // filtered texture color
-					dayLight * shadow_color * shadow_int);                 // reflected filtered sunlight/moonlight
+		shadow_int *= f_adj_shadow_strength;
+		
+		// calculate fragment color from components:
+		col.rgb =
+				adjusted_night_ratio * col.rgb + // artificial light
+				(1.0 - adjusted_night_ratio) * ( // natural light
+						col.rgb * (1.0 - shadow_int * (1.0 - shadow_color)) +  // filtered texture color
+						dayLight * shadow_color * shadow_int);                 // reflected filtered sunlight/moonlight
+	}
 #endif
 
 #if ENABLE_TONE_MAPPING
diff --git a/client/shaders/nodes_shader/opengl_vertex.glsl b/client/shaders/nodes_shader/opengl_vertex.glsl
index 95cd138a8..5e77ac719 100644
--- a/client/shaders/nodes_shader/opengl_vertex.glsl
+++ b/client/shaders/nodes_shader/opengl_vertex.glsl
@@ -195,34 +195,35 @@ void main(void)
 	varColor = clamp(color, 0.0, 1.0);
 
 #ifdef ENABLE_DYNAMIC_SHADOWS
-	vec3 nNormal = normalize(vNormal);
-	cosLight = dot(nNormal, -v_LightDirection);
-	
-	// Calculate normal offset scale based on the texel size adjusted for 
-	// curvature of the SM texture. This code must be change together with
-	// getPerspectiveFactor or any light-space transformation.
-	vec3 eyeToVertex = worldPosition - eyePosition + cameraOffset;
-	// Distance from the vertex to the player
-	float distanceToPlayer = length(eyeToVertex - v_LightDirection * dot(eyeToVertex, v_LightDirection)) / f_shadowfar;
-	// perspective factor estimation according to the 
-	float perspectiveFactor = distanceToPlayer * bias0 + bias1;
-	float texelSize = f_shadowfar * perspectiveFactor * perspectiveFactor /
-			(f_textureresolution * bias1  - perspectiveFactor * bias0);
-	float slopeScale = clamp(pow(1.0 - cosLight*cosLight, 0.5), 0.0, 1.0);
-	normalOffsetScale = texelSize * slopeScale;
-
-	if (f_timeofday < 0.2) {
-		adj_shadow_strength = f_shadow_strength * 0.5 *
-			(1.0 - mtsmoothstep(0.18, 0.2, f_timeofday));
-	} else if (f_timeofday >= 0.8) {
-		adj_shadow_strength = f_shadow_strength * 0.5 *
-			mtsmoothstep(0.8, 0.83, f_timeofday);
-	} else {
-		adj_shadow_strength = f_shadow_strength *
-			mtsmoothstep(0.20, 0.25, f_timeofday) *
-			(1.0 - mtsmoothstep(0.7, 0.8, f_timeofday));
+	if (f_shadow_strength > 0.0) {
+		vec3 nNormal = normalize(vNormal);
+		cosLight = dot(nNormal, -v_LightDirection);
+		
+		// Calculate normal offset scale based on the texel size adjusted for 
+		// curvature of the SM texture. This code must be change together with
+		// getPerspectiveFactor or any light-space transformation.
+		vec3 eyeToVertex = worldPosition - eyePosition + cameraOffset;
+		// Distance from the vertex to the player
+		float distanceToPlayer = length(eyeToVertex - v_LightDirection * dot(eyeToVertex, v_LightDirection)) / f_shadowfar;
+		// perspective factor estimation according to the 
+		float perspectiveFactor = distanceToPlayer * bias0 + bias1;
+		float texelSize = f_shadowfar * perspectiveFactor * perspectiveFactor /
+				(f_textureresolution * bias1  - perspectiveFactor * bias0);
+		float slopeScale = clamp(pow(1.0 - cosLight*cosLight, 0.5), 0.0, 1.0);
+		normalOffsetScale = texelSize * slopeScale;
+
+		if (f_timeofday < 0.2) {
+			adj_shadow_strength = f_shadow_strength * 0.5 *
+				(1.0 - mtsmoothstep(0.18, 0.2, f_timeofday));
+		} else if (f_timeofday >= 0.8) {
+			adj_shadow_strength = f_shadow_strength * 0.5 *
+				mtsmoothstep(0.8, 0.83, f_timeofday);
+		} else {
+			adj_shadow_strength = f_shadow_strength *
+				mtsmoothstep(0.20, 0.25, f_timeofday) *
+				(1.0 - mtsmoothstep(0.7, 0.8, f_timeofday));
+		}
+		f_normal_length = length(vNormal);
 	}
-	f_normal_length = length(vNormal);
 #endif
-
 }
diff --git a/client/shaders/object_shader/opengl_fragment.glsl b/client/shaders/object_shader/opengl_fragment.glsl
index fdfcec0c8..edb9d2bb1 100644
--- a/client/shaders/object_shader/opengl_fragment.glsl
+++ b/client/shaders/object_shader/opengl_fragment.glsl
@@ -34,6 +34,8 @@ const float fogShadingParameter = 1.0 / (1.0 - fogStart);
 	uniform float f_textureresolution;
 	uniform mat4 m_ShadowViewProj;
 	uniform float f_shadowfar;
+	uniform float f_timeofday;
+	uniform float f_shadow_strength;
 	varying float normalOffsetScale;
 	varying float adj_shadow_strength;
 	varying float cosLight;
@@ -470,55 +472,57 @@ void main(void)
 	col.rgb *= vIDiff;
 
 #ifdef ENABLE_DYNAMIC_SHADOWS
-	float shadow_int = 0.0;
-	vec3 shadow_color = vec3(0.0, 0.0, 0.0);
-	vec3 posLightSpace = getLightSpacePosition();
+	if (f_shadow_strength > 0.0) {
+		float shadow_int = 0.0;
+		vec3 shadow_color = vec3(0.0, 0.0, 0.0);
+		vec3 posLightSpace = getLightSpacePosition();
 
-	float distance_rate = (1 - pow(clamp(2.0 * length(posLightSpace.xy - 0.5),0.0,1.0), 20.0));
-	float f_adj_shadow_strength = max(adj_shadow_strength-mtsmoothstep(0.9,1.1,  posLightSpace.z  ),0.0);
+		float distance_rate = (1 - pow(clamp(2.0 * length(posLightSpace.xy - 0.5),0.0,1.0), 20.0));
+		float f_adj_shadow_strength = max(adj_shadow_strength-mtsmoothstep(0.9,1.1,  posLightSpace.z  ),0.0);
 
-	if (distance_rate > 1e-7) {
+		if (distance_rate > 1e-7) {
 	
 #ifdef COLORED_SHADOWS
-		vec4 visibility;
-		if (cosLight > 0.0)
-			visibility = getShadowColor(ShadowMapSampler, posLightSpace.xy, posLightSpace.z);
-		else
-			visibility = vec4(1.0, 0.0, 0.0, 0.0);
-		shadow_int = visibility.r;
-		shadow_color = visibility.gba;
+			vec4 visibility;
+			if (cosLight > 0.0)
+				visibility = getShadowColor(ShadowMapSampler, posLightSpace.xy, posLightSpace.z);
+			else
+				visibility = vec4(1.0, 0.0, 0.0, 0.0);
+			shadow_int = visibility.r;
+			shadow_color = visibility.gba;
 #else
-		if (cosLight > 0.0)
-			shadow_int = getShadow(ShadowMapSampler, posLightSpace.xy, posLightSpace.z);
-		else
-			shadow_int = 1.0;
+			if (cosLight > 0.0)
+				shadow_int = getShadow(ShadowMapSampler, posLightSpace.xy, posLightSpace.z);
+			else
+				shadow_int = 1.0;
 #endif
-		shadow_int *= distance_rate;
-		shadow_int = clamp(shadow_int, 0.0, 1.0);
+			shadow_int *= distance_rate;
+			shadow_int = clamp(shadow_int, 0.0, 1.0);
 
-	}
+		}
 
-	// turns out that nightRatio falls off much faster than
-	// actual brightness of artificial light in relation to natual light.
-	// Power ratio was measured on torches in MTG (brightness = 14).
-	float adjusted_night_ratio = pow(max(0.0, nightRatio), 0.6);
-
-	// cosine of the normal-to-light angle when
-	// we start to apply self-shadowing
-	const float self_shadow_cutoff_cosine = 0.14;
-	if (f_normal_length != 0 && cosLight < self_shadow_cutoff_cosine) {
-		shadow_int = max(shadow_int, 1 - clamp(cosLight, 0.0, self_shadow_cutoff_cosine)/self_shadow_cutoff_cosine);
-		shadow_color = mix(vec3(0.0), shadow_color, min(cosLight, self_shadow_cutoff_cosine)/self_shadow_cutoff_cosine);
-	}
+		// turns out that nightRatio falls off much faster than
+		// actual brightness of artificial light in relation to natual light.
+		// Power ratio was measured on torches in MTG (brightness = 14).
+		float adjusted_night_ratio = pow(max(0.0, nightRatio), 0.6);
+
+		// cosine of the normal-to-light angle when
+		// we start to apply self-shadowing
+		const float self_shadow_cutoff_cosine = 0.14;
+		if (f_normal_length != 0 && cosLight < self_shadow_cutoff_cosine) {
+			shadow_int = max(shadow_int, 1 - clamp(cosLight, 0.0, self_shadow_cutoff_cosine)/self_shadow_cutoff_cosine);
+			shadow_color = mix(vec3(0.0), shadow_color, min(cosLight, self_shadow_cutoff_cosine)/self_shadow_cutoff_cosine);
+		}
 
-	shadow_int *= f_adj_shadow_strength;
-	
-	// calculate fragment color from components:
-	col.rgb =
-			adjusted_night_ratio * col.rgb + // artificial light
-			(1.0 - adjusted_night_ratio) * ( // natural light
-					col.rgb * (1.0 - shadow_int * (1.0 - shadow_color)) +  // filtered texture color
-					dayLight * shadow_color * shadow_int);                 // reflected filtered sunlight/moonlight
+		shadow_int *= f_adj_shadow_strength;
+
+		// calculate fragment color from components:
+		col.rgb =
+				adjusted_night_ratio * col.rgb + // artificial light
+				(1.0 - adjusted_night_ratio) * ( // natural light
+						col.rgb * (1.0 - shadow_int * (1.0 - shadow_color)) +  // filtered texture color
+						dayLight * shadow_color * shadow_int);                 // reflected filtered sunlight/moonlight
+	}
 #endif
 
 #if ENABLE_TONE_MAPPING
diff --git a/client/shaders/object_shader/opengl_vertex.glsl b/client/shaders/object_shader/opengl_vertex.glsl
index 185551c58..ff0067302 100644
--- a/client/shaders/object_shader/opengl_vertex.glsl
+++ b/client/shaders/object_shader/opengl_vertex.glsl
@@ -105,33 +105,35 @@ void main(void)
 
 
 #ifdef ENABLE_DYNAMIC_SHADOWS
-	vec3 nNormal = normalize(vNormal);
-	cosLight = dot(nNormal, -v_LightDirection);
-
-	// Calculate normal offset scale based on the texel size adjusted for 
-	// curvature of the SM texture. This code must be change together with
-	// getPerspectiveFactor or any light-space transformation.
-	vec3 eyeToVertex = worldPosition - eyePosition + cameraOffset;
-	// Distance from the vertex to the player
-	float distanceToPlayer = length(eyeToVertex - v_LightDirection * dot(eyeToVertex, v_LightDirection)) / f_shadowfar;
-	// perspective factor estimation according to the 
-	float perspectiveFactor = distanceToPlayer * bias0 + bias1;
-	float texelSize = f_shadowfar * perspectiveFactor * perspectiveFactor /
-			(f_textureresolution * bias1  - perspectiveFactor * bias0);
-	float slopeScale = clamp(pow(1.0 - cosLight*cosLight, 0.5), 0.0, 1.0);
-	normalOffsetScale = texelSize * slopeScale;
-	
-	if (f_timeofday < 0.2) {
-		adj_shadow_strength = f_shadow_strength * 0.5 *
-			(1.0 - mtsmoothstep(0.18, 0.2, f_timeofday));
-	} else if (f_timeofday >= 0.8) {
-		adj_shadow_strength = f_shadow_strength * 0.5 *
-			mtsmoothstep(0.8, 0.83, f_timeofday);
-	} else {
-		adj_shadow_strength = f_shadow_strength *
-			mtsmoothstep(0.20, 0.25, f_timeofday) *
-			(1.0 - mtsmoothstep(0.7, 0.8, f_timeofday));
+	if (f_shadow_strength > 0.0) {
+		vec3 nNormal = normalize(vNormal);
+		cosLight = dot(nNormal, -v_LightDirection);
+
+		// Calculate normal offset scale based on the texel size adjusted for 
+		// curvature of the SM texture. This code must be change together with
+		// getPerspectiveFactor or any light-space transformation.
+		vec3 eyeToVertex = worldPosition - eyePosition + cameraOffset;
+		// Distance from the vertex to the player
+		float distanceToPlayer = length(eyeToVertex - v_LightDirection * dot(eyeToVertex, v_LightDirection)) / f_shadowfar;
+		// perspective factor estimation according to the
+		float perspectiveFactor = distanceToPlayer * bias0 + bias1;
+		float texelSize = f_shadowfar * perspectiveFactor * perspectiveFactor /
+				(f_textureresolution * bias1  - perspectiveFactor * bias0);
+		float slopeScale = clamp(pow(1.0 - cosLight*cosLight, 0.5), 0.0, 1.0);
+		normalOffsetScale = texelSize * slopeScale;
+
+		if (f_timeofday < 0.2) {
+			adj_shadow_strength = f_shadow_strength * 0.5 *
+				(1.0 - mtsmoothstep(0.18, 0.2, f_timeofday));
+		} else if (f_timeofday >= 0.8) {
+			adj_shadow_strength = f_shadow_strength * 0.5 *
+				mtsmoothstep(0.8, 0.83, f_timeofday);
+		} else {
+			adj_shadow_strength = f_shadow_strength *
+				mtsmoothstep(0.20, 0.25, f_timeofday) *
+				(1.0 - mtsmoothstep(0.7, 0.8, f_timeofday));
+		}
+		f_normal_length = length(vNormal);
 	}
-	f_normal_length = length(vNormal);
 #endif
 }