Merge branch 'master' of https://github.com/minetest/minetest

3 files changed, 65 insertions, 20 deletions

diff --git a/client/shaders/shadow_shaders/pass1_trans_fragment.glsl b/client/shaders/shadow_shaders/pass1_trans_fragment.glsl
index 9f9e5be8c..b267c2214 100644
--- a/client/shaders/shadow_shaders/pass1_trans_fragment.glsl
+++ b/client/shaders/shadow_shaders/pass1_trans_fragment.glsl
@@ -2,6 +2,8 @@ uniform sampler2D ColorMapSampler;
 varying vec4 tPos;
 
 #ifdef COLORED_SHADOWS
+varying vec3 varColor;
+
 // c_precision of 128 fits within 7 base-10 digits
 const float c_precision = 128.0;
 const float c_precisionp1 = c_precision + 1.0;
@@ -30,7 +32,9 @@ void main()
 
 	//col.rgb = col.a == 1.0 ? vec3(1.0) : col.rgb;
 #ifdef COLORED_SHADOWS
-	float packedColor = packColor(mix(col.rgb, black, col.a));
+	col.rgb *= varColor.rgb;
+	// premultiply color alpha (see-through side)
+	float packedColor = packColor(col.rgb * (1.0 - col.a));
 	gl_FragColor = vec4(depth, packedColor, 0.0,1.0);
 #else
 	gl_FragColor = vec4(depth, 0.0, 0.0, 1.0);
diff --git a/client/shaders/shadow_shaders/pass1_trans_vertex.glsl b/client/shaders/shadow_shaders/pass1_trans_vertex.glsl
index ca59f2796..244d2562a 100644
--- a/client/shaders/shadow_shaders/pass1_trans_vertex.glsl
+++ b/client/shaders/shadow_shaders/pass1_trans_vertex.glsl
@@ -1,26 +1,50 @@
 uniform mat4 LightMVP; // world matrix
+uniform vec4 CameraPos;
 varying vec4 tPos;
+#ifdef COLORED_SHADOWS
+varying vec3 varColor;
+#endif
 
-const float bias0 = 0.9;
-const float zPersFactor = 0.5;
-const float bias1 = 1.0 - bias0 + 1e-6;
+uniform float xyPerspectiveBias0;
+uniform float xyPerspectiveBias1;
+uniform float zPerspectiveBias;
 
-vec4 getPerspectiveFactor(in vec4 shadowPosition)
+vec4 getRelativePosition(in vec4 position)
 {
-	float pDistance = length(shadowPosition.xy);
-	float pFactor = pDistance * bias0 + bias1;
-	shadowPosition.xyz *= vec3(vec2(1.0 / pFactor), zPersFactor);
+	vec2 l = position.xy - CameraPos.xy;
+	vec2 s = l / abs(l);
+	s = (1.0 - s * CameraPos.xy);
+	l /= s;
+	return vec4(l, s);
+}
 
-	return shadowPosition;
+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;
+}
 
 void main()
 {
 	vec4 pos = LightMVP * gl_Vertex;
 
-	tPos = getPerspectiveFactor(LightMVP * gl_Vertex);
+	tPos = applyPerspectiveDistortion(LightMVP * gl_Vertex);
 
 	gl_Position = vec4(tPos.xyz, 1.0);
 	gl_TexCoord[0].st = gl_MultiTexCoord0.st;
+
+#ifdef COLORED_SHADOWS
+	varColor = gl_Color.rgb;
+#endif
 }
diff --git a/client/shaders/shadow_shaders/pass1_vertex.glsl b/client/shaders/shadow_shaders/pass1_vertex.glsl
index a6d8b3db8..1dceb93c6 100644
--- a/client/shaders/shadow_shaders/pass1_vertex.glsl
+++ b/client/shaders/shadow_shaders/pass1_vertex.glsl
@@ -1,26 +1,43 @@
 uniform mat4 LightMVP; // world matrix
+uniform vec4 CameraPos; // camera position
 varying vec4 tPos;
 
-const float bias0 = 0.9;
-const float zPersFactor = 0.5;
-const float bias1 = 1.0 - bias0 + 1e-6;
+uniform float xyPerspectiveBias0;
+uniform float xyPerspectiveBias1;
+uniform float zPerspectiveBias;
 
-vec4 getPerspectiveFactor(in vec4 shadowPosition)
+vec4 getRelativePosition(in vec4 position)
 {
-	float pDistance = length(shadowPosition.xy);
-	float pFactor = pDistance * bias0 + bias1;
-	shadowPosition.xyz *= vec3(vec2(1.0 / pFactor), zPersFactor);
+	vec2 l = position.xy - CameraPos.xy;
+	vec2 s = l / abs(l);
+	s = (1.0 - s * CameraPos.xy);
+	l /= s;
+	return vec4(l, s);
+}
 
-	return shadowPosition;
+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;
+}
 
 void main()
 {
 	vec4 pos = LightMVP * gl_Vertex;
 
-	tPos = getPerspectiveFactor(pos);
+	tPos = applyPerspectiveDistortion(pos);
 
 	gl_Position = vec4(tPos.xyz, 1.0);
-	gl_TexCoord[0].st = gl_MultiTexCoord0.st;
+	gl_TexCoord[0] = gl_TextureMatrix[0] * gl_MultiTexCoord0;
 }