1 files changed, 46 insertions, 0 deletions
diff --git a/client/shaders/object_shader/opengl_vertex.glsl b/client/shaders/object_shader/opengl_vertex.glsl
index f26224e82..f135ab9dc 100644
--- a/client/shaders/object_shader/opengl_vertex.glsl
+++ b/client/shaders/object_shader/opengl_vertex.glsl
@@ -13,12 +13,37 @@ varying mediump vec2 varTexCoord;
 centroid varying vec2 varTexCoord;
 #endif
 
+#ifdef ENABLE_DYNAMIC_SHADOWS
+	// shadow uniforms
+	uniform vec3 v_LightDirection;
+	uniform float f_textureresolution;
+	uniform mat4 m_ShadowViewProj;
+	uniform float f_shadowfar;
+	uniform float f_shadow_strength;
+	uniform float f_timeofday;
+	varying float cosLight;
+	varying float normalOffsetScale;
+	varying float adj_shadow_strength;
+	varying float f_normal_length;
+#endif
+
 varying vec3 eyeVec;
 varying float vIDiff;
 
 const float e = 2.718281828459;
 const float BS = 10.0;
 
+#ifdef ENABLE_DYNAMIC_SHADOWS
+// 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)
+{
+	float t = clamp((x - edge0) / (edge1 - edge0), 0.0, 1.0);
+	return t * t * (3.0 - 2.0 * t);
+}
+#endif
+
+
 float directional_ambient(vec3 normal)
 {
 	vec3 v = normal * normal;
@@ -54,4 +79,25 @@ void main(void)
 #else
 	varColor = inVertexColor;
 #endif
+
+#ifdef ENABLE_DYNAMIC_SHADOWS
+
+	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);
+
+#endif
 }