From 7a71132806434fa2e534614c71ebc29b40659b45 Mon Sep 17 00:00:00 2001
From: Zeno Rogue <zeno@attnam.com>
Date: Fri, 17 Apr 2020 15:01:55 +0200
Subject: [PATCH] shaded rug

---
 drawing.cpp |  2 ++
 rug.cpp     | 10 ++++------
 shaders.cpp | 13 +++++++++++--
 3 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/drawing.cpp b/drawing.cpp
index a2ed0460..015f262e 100644
--- a/drawing.cpp
+++ b/drawing.cpp
@@ -36,6 +36,7 @@ static const int POLY_INTENSE = (1<<23);        // extra intense colors
 static const int POLY_DEBUG = (1<<24);          // debug this shape
 static const int POLY_PRINTABLE = (1<<25);      // these walls are printable
 static const int POLY_FAT = (1<<26);            // fatten this model in WRL export (used for Rug)
+static const int POLY_SHADE_TEXTURE = (1<<27);  // texture has 'z' coordinate for shading
 
 /** \brief A graphical element that can be drawn. Objects are not drawn immediately but rather queued.
  *
@@ -596,6 +597,7 @@ void dqi_poly::gldraw() {
   
   if(tinf) {
     glhr::be_textured();
+    if(flags & POLY_SHADE_TEXTURE) current_display->next_shader_flags |= GF_TEXTURE_SHADED;
     glBindTexture(GL_TEXTURE_2D, tinf->texture_id);
     glhr::vertices_texture(v, tinf->tvertices, offset, offset_texture);
     ioffset = 0;
diff --git a/rug.cpp b/rug.cpp
index 81b90a29..fde4894a 100644
--- a/rug.cpp
+++ b/rug.cpp
@@ -987,20 +987,18 @@ void drawTriangle(triangle& t) {
     if(!t.m[i]->valid) return;
     }
   
-  /*
   ld col = 1;
-  if(num == 3) {
-    hyperpoint hc = (h[1] - h[0]) ^ (h[2] - h[0]);  
+  if(true) {
+    hyperpoint hc = (t.m[1]->native - t.m[0]->native) ^ (t.m[2]->native - t.m[0]->native);  
     double hch = hypot_d(3, hc);  
     col = (2 + hc[0]/hch) / 3;
     }
-  */
 
   for(int i=0; i<3; i++)  {
     if(t.m[i]->native[3] != 1)
       println(hlog, "bad point: ", t.m[i]->native);
     curvepoint(t.m[i]->native);
-    tinf.tvertices.push_back(glhr::pointtogl(point3(t.m[i]->x1, t.m[i]->y1, 0)));
+    tinf.tvertices.push_back(glhr::pointtogl(point3(t.m[i]->x1, t.m[i]->y1, col)));
     }
   }
 
@@ -1081,7 +1079,7 @@ EX void drawRugScene() {
   rug.V = rugView;
   rug.offset_texture = 0;
   rug.tinf = &tinf;
-  rug.flags = POLY_TRIANGLES | POLY_FAT | POLY_PRINTABLE | POLY_ALWAYS_IN | POLY_ISSIDE;
+  rug.flags = POLY_TRIANGLES | POLY_FAT | POLY_PRINTABLE | POLY_ALWAYS_IN | POLY_ISSIDE | POLY_SHADE_TEXTURE;
 
   dynamicval<projection_configuration> p(pconf, rconf);
   calcparam();
diff --git a/shaders.cpp b/shaders.cpp
index 85c4b05e..1921dff3 100644
--- a/shaders.cpp
+++ b/shaders.cpp
@@ -16,8 +16,9 @@ constexpr flagtype GF_TEXTURE  = 1;
 constexpr flagtype GF_VARCOLOR = 2;
 constexpr flagtype GF_LIGHTFOG = 4;
 constexpr flagtype GF_LEVELS   = 8;
+constexpr flagtype GF_TEXTURE_SHADED  = 16;
 
-constexpr flagtype GF_which    = 15;
+constexpr flagtype GF_which    = 31;
 
 constexpr flagtype SF_PERS3        = 256;
 constexpr flagtype SF_BAND         = 512;
@@ -62,7 +63,15 @@ shared_ptr<glhr::GLprogram> write_shader(flagtype shader_flags) {
   varying += "varying mediump vec4 vColor;\n";
 
   fmain += "gl_FragColor = vColor;\n";
-  if(shader_flags & GF_TEXTURE) {
+  if(shader_flags & GF_TEXTURE_SHADED) {
+    vsh += "attribute mediump vec3 aTexture;\n";
+    varying += "varying mediump vec3 vTexCoord;\n";
+    fsh += "uniform mediump sampler2D tTexture;\n";
+    vmain += "vTexCoord = aTexture;\n";
+    fmain += "gl_FragColor *= texture2D(tTexture, vTexCoord.xy);\n";
+    fmain += "gl_FragColor.rgb *= vTexCoord.z;\n";
+    }
+  else if(shader_flags & GF_TEXTURE) {
     vsh += "attribute mediump vec2 aTexture;\n";
     varying += "varying mediump vec2 vTexCoord;\n";
     fsh += "uniform mediump sampler2D tTexture;\n";