From a2183151be0580b751182d9bb3191ca8f54af885 Mon Sep 17 00:00:00 2001
From: jgk <justin.g.kruger@gmail.com>
Date: Sat, 20 Mar 2021 12:28:19 +0100
Subject: [PATCH] Lower walls and performance improvement for shadows

---
 shader/wallShadow.geom | 24 ++++++++++++++----------
 src/Dodge/Rendering.hs |  4 ++--
 src/Picture/Render.hs  |  6 +++---
 3 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/shader/wallShadow.geom b/shader/wallShadow.geom
index 99a7fa666..98efbb3aa 100644
--- a/shader/wallShadow.geom
+++ b/shader/wallShadow.geom
@@ -6,29 +6,28 @@ uniform vec2 lightPos;
 uniform mat4 perpMat;
 uniform mat4 worldMat;
 
-vec2 lightPosa = lightPos;
+vec2 lightPosa = ( perpMat * vec4(lightPos,0,1) ).xy;
 
 vec4 shift (vec4 p)
-{ return vec4 (p.xy + (200 * (p.xy-lightPosa)), 0 , 1);
+{ return vec4 (p.xy + (200 * (p.xy-lightPos)), 0 , 1);
 }
 float isLHS (vec2 startV, vec2 testV)
 {
     return sign( -startV.x * testV.y + startV.y * testV.x);
 }
-// construct a box with opening on bottom face
-
+// construct a box with openings on bottom face and face away from wall
 void main()
 {
 vec4 p1 = vec4 (gl_in[0].gl_Position.xy,0,1);
 vec4 p2 = vec4 (gl_in[0].gl_Position.zw,0,1);
-if (isLHS (p1.xy - lightPosa, p2.xy - lightPosa) < 0)
+if (isLHS (p1.xy - lightPos, p2.xy - lightPos) < 0)
 {
-vec4 p3 = vec4 (p1.xy,-0.5,1);
-vec4 p4 = vec4 (p2.xy,-0.5,1);
+vec4 p3 = vec4 (p1.xy,-0.2,1);
+vec4 p4 = vec4 (p2.xy,-0.2,1);
 vec4 p5 = shift(p1);
 vec4 p6 = shift(p2);
-vec4 p7 = vec4 (p6.xy,-0.5,1);
-vec4 p8 = vec4 (p5.xy,-0.5,1);
+vec4 p7 = vec4 (p6.xy,-0.2,1);
+vec4 p8 = vec4 (p5.xy,-0.2,1);
 
 vec4 a1 = perpMat * p1;
 vec4 a2 = perpMat * p2;
@@ -39,6 +38,11 @@ vec4 a6 = perpMat * p6;
 vec4 a7 = perpMat * p7;
 vec4 a8 = perpMat * p8;
 
+//  gl_Position = a1; EmitVertex();
+//  gl_Position = a5; EmitVertex();
+//  gl_Position = a2; EmitVertex();
+//  gl_Position = a6; EmitVertex();
+
   gl_Position = a4; EmitVertex();
   gl_Position = a3; EmitVertex();
   gl_Position = a7; EmitVertex();
@@ -50,7 +54,7 @@ vec4 a8 = perpMat * p8;
   gl_Position = a2; EmitVertex();
   gl_Position = a7; EmitVertex();
   gl_Position = a6; EmitVertex();
-//  gl_Position = a5; EmitVertex();
+
   EndPrimitive();
 } else {}
 }
diff --git a/src/Dodge/Rendering.hs b/src/Dodge/Rendering.hs
index 6e2669140..7f9b4c689 100644
--- a/src/Dodge/Rendering.hs
+++ b/src/Dodge/Rendering.hs
@@ -122,8 +122,8 @@ worldPictures w
                 where tst x y sc t = translate x y $ scale sc sc $ color white $ text t
 
 testPic :: World -> [Picture]
-testPic w = --[blank]
-     [setLayer 1 $ onLayerL [99] $ bezierQuad white red 5 5 (00,00) (300,305) (50,000) ]
+testPic w = [blank]
+    -- [setLayer 1 $ onLayerL [99] $ bezierQuad white red 5 5 (00,00) (300,305) (50,000) ]
     -- $ uncurry translate (mouseWorldPos w) 
 
 
diff --git a/src/Picture/Render.hs b/src/Picture/Render.hs
index fe0c51b8d..157b2e7a4 100644
--- a/src/Picture/Render.hs
+++ b/src/Picture/Render.hs
@@ -68,9 +68,7 @@ renderPicture' pdata rot zoom (tranx,trany) (winx,winy) wallPoints lightPoints
 
     currentProgram $= Just (_shaderProgram $ _wallShadowShader pdata)
     uniform (head $ fromJust $ _shaderCustomUnis $ _wallShadowShader pdata)
-            $= Vector2 viewFromx viewFromy  -- hopefully this draws as if from the center
-                                     -- it does, but this is not correct when
-                                     -- the camera center is not the player position
+            $= Vector2 viewFromx viewFromy  
     pmat <- (newMatrix RowMajor 
                 $ perspectiveMatrix rot zoom (tranx,trany) (winx,winy) (viewFromx,viewFromy)
             ) :: IO (GLmatrix GLfloat)
@@ -85,6 +83,7 @@ renderPicture' pdata rot zoom (tranx,trany) (winx,winy) wallPoints lightPoints
     stencilTest $= Enabled
     forM_ lightPoints $ \(x,y,r,lum) -> do
 --        depthFunc $= Just Less
+        colorMask $= (Color4 Disabled Disabled Disabled Disabled)
         clear [StencilBuffer]
         cullFace $= Just Back
 --        stencilOp $= (OpKeep,OpKeep,OpReplace)
@@ -103,6 +102,7 @@ renderPicture' pdata rot zoom (tranx,trany) (winx,winy) wallPoints lightPoints
 
         cullFace $= Nothing
         
+        colorMask $= (Color4 Enabled Enabled Enabled Enabled)
         let lightPtr = (\(_,ptr,_) -> ptr) $ head 
                             $ _vaoBufferTargets $ _shaderVAO $ _lightSourceShader pdata
             (x',y') = zTran $ rotateV (0 - rot) $ (x,y) -.- (tranx,trany)