1 files changed, 101 insertions, 23 deletions

diff --git a/client/shaders/object_shader/opengl_vertex.glsl b/client/shaders/object_shader/opengl_vertex.glsl
index f135ab9dc..dc9c70cdf 100644
--- a/client/shaders/object_shader/opengl_vertex.glsl
+++ b/client/shaders/object_shader/opengl_vertex.glsl
@@ -1,7 +1,10 @@
 uniform mat4 mWorld;
-
+uniform vec3 dayLight;
 uniform vec3 eyePosition;
 uniform float animationTimer;
+uniform vec4 emissiveColor;
+uniform vec3 cameraOffset;
+
 
 varying vec3 vNormal;
 varying vec3 vPosition;
@@ -21,19 +24,54 @@ centroid varying vec2 varTexCoord;
 	uniform float f_shadowfar;
 	uniform float f_shadow_strength;
 	uniform float f_timeofday;
+	uniform vec4 CameraPos;
+
 	varying float cosLight;
-	varying float normalOffsetScale;
 	varying float adj_shadow_strength;
 	varying float f_normal_length;
+	varying vec3 shadow_position;
+	varying float perspective_factor;
 #endif
 
 varying vec3 eyeVec;
+varying float nightRatio;
+// Color of the light emitted by the light sources.
+const vec3 artificialLight = vec3(1.04, 1.04, 1.04);
 varying float vIDiff;
-
 const float e = 2.718281828459;
 const float BS = 10.0;
+uniform float xyPerspectiveBias0;
+uniform float xyPerspectiveBias1;
+uniform float zPerspectiveBias;
 
 #ifdef ENABLE_DYNAMIC_SHADOWS
+
+vec4 getRelativePosition(in vec4 position)
+{
+	vec2 l = position.xy - CameraPos.xy;
+	vec2 s = l / abs(l);
+	s = (1.0 - s * CameraPos.xy);
+	l /= s;
+	return vec4(l, s);
+}
+
+float getPerspectiveFactor(in vec4 relativePosition)
+{
+	float pDistance = length(relativePosition.xy);
+	float pFactor = pDistance * xyPerspectiveBias0 + xyPerspectiveBias1;
+	return pFactor;
+}
+
+vec4 applyPerspectiveDistortion(in vec4 position)
+{
+	vec4 l = getRelativePosition(position);
+	float pFactor = getPerspectiveFactor(l);
+	l.xy /= pFactor;
+	position.xy = l.xy * l.zw + CameraPos.xy;
+	position.z *= zPerspectiveBias;
+	return position;
+}
+
 // custom smoothstep implementation because it's not defined in glsl1.2
 // https://docs.gl/sl4/smoothstep
 float mtsmoothstep(in float edge0, in float edge1, in float x)
@@ -60,7 +98,7 @@ void main(void)
 	gl_Position = mWorldViewProj * inVertexPosition;
 
 	vPosition = gl_Position.xyz;
-	vNormal = inVertexNormal;
+	vNormal = (mWorld * vec4(inVertexNormal, 0.0)).xyz;
 	worldPosition = (mWorld * inVertexPosition).xyz;
 	eyeVec = -(mWorldView * inVertexPosition).xyz;
 
@@ -75,29 +113,69 @@ void main(void)
 #endif
 
 #ifdef GL_ES
-	varColor = inVertexColor.bgra;
+	vec4 color = inVertexColor.bgra;
 #else
-	varColor = inVertexColor;
+	vec4 color = inVertexColor;
 #endif
 
-#ifdef ENABLE_DYNAMIC_SHADOWS
+	color *= emissiveColor;
 
-	cosLight = max(0.0, dot(vNormal, -v_LightDirection));
-	float texelSize = 0.51;
-	float slopeScale = clamp(1.0 - cosLight, 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);
+	// The alpha gives the ratio of sunlight in the incoming light.
+	nightRatio = 1.0 - color.a;
+	color.rgb = color.rgb * (color.a * dayLight.rgb +
+		nightRatio * artificialLight.rgb) * 2.0;
+	color.a = 1.0;
 
+	// Emphase blue a bit in darker places
+	// See C++ implementation in mapblock_mesh.cpp final_color_blend()
+	float brightness = (color.r + color.g + color.b) / 3.0;
+	color.b += max(0.0, 0.021 - abs(0.2 * brightness - 0.021) +
+		0.07 * brightness);
+
+	varColor = clamp(color, 0.0, 1.0);
+
+
+#ifdef ENABLE_DYNAMIC_SHADOWS
+	if (f_shadow_strength > 0.0) {
+		vec3 nNormal = normalize(vNormal);
+		f_normal_length = length(vNormal);
+
+		/* normalOffsetScale is in world coordinates (1/10th of a meter)
+		   z_bias is in light space coordinates */
+		float normalOffsetScale, z_bias;
+		float pFactor = getPerspectiveFactor(getRelativePosition(m_ShadowViewProj * mWorld * inVertexPosition));
+		if (f_normal_length > 0.0) {
+			nNormal = normalize(vNormal);
+			cosLight = dot(nNormal, -v_LightDirection);
+			float sinLight = pow(1 - pow(cosLight, 2.0), 0.5);
+			normalOffsetScale = 0.1 * pFactor * pFactor * sinLight * min(f_shadowfar, 500.0) / 
+					xyPerspectiveBias1 / f_textureresolution;
+			z_bias = 1e3 * sinLight / cosLight * (0.5 + f_textureresolution / 1024.0);
+		}
+		else {
+			nNormal = vec3(0.0);
+			cosLight = clamp(dot(v_LightDirection, normalize(vec3(v_LightDirection.x, 0.0, v_LightDirection.z))), 1e-2, 1.0);
+			float sinLight = pow(1 - pow(cosLight, 2.0), 0.5);
+			normalOffsetScale = 0.0;
+			z_bias = 3.6e3 * sinLight / cosLight;
+		}
+		z_bias *= pFactor * pFactor / f_textureresolution / f_shadowfar;
+
+		shadow_position = applyPerspectiveDistortion(m_ShadowViewProj * mWorld * (inVertexPosition + vec4(normalOffsetScale * nNormal, 0.0))).xyz;
+		shadow_position.z -= z_bias;
+		perspective_factor = pFactor;
+
+		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));
+		}
+	}
 #endif
 }