From 9b61093de417a01ec298ba239d1d7b72920619af Mon Sep 17 00:00:00 2001
From: ktyl <me@ktyl.dev>
Date: Fri, 13 Aug 2021 19:12:39 +0100
Subject: [PATCH] use first pass depth and normal data

---
 shader/include/constants.glsl |  4 ++--
 shader/root/rt.glsl           | 40 ++++++++++++++++++++---------------
 shader/root/rtpre.glsl        |  2 +-
 src/main.c                    |  1 -
 src/sphere.c                  |  2 +-
 todo.md                       |  8 +++----
 6 files changed, 31 insertions(+), 26 deletions(-)

diff --git a/shader/include/constants.glsl b/shader/include/constants.glsl
index bcba6b7..774a06e 100644
--- a/shader/include/constants.glsl
+++ b/shader/include/constants.glsl
@@ -1,5 +1,5 @@
-const float INF = 100.0;
+const float INF = 17.0;
 const float PI = 3.14159;
 const float E = 2.71828;
 const int SAMPLES = 1;
-const int BOUNCES = 4;
+const int BOUNCES = 8;
diff --git a/shader/root/rt.glsl b/shader/root/rt.glsl
index e778f86..f84c496 100644
--- a/shader/root/rt.glsl
+++ b/shader/root/rt.glsl
@@ -43,27 +43,33 @@ void main()
 
     vec2 uv = pixelUv(pixelCoords, dims);
 
-    for (int i = 0; i < SAMPLES; i++) 
-    {
-        // create a ray from the uv
-        Ray ray = createCameraRay(uv);
-
-        // trace the rays path around the scene
-        for (int j = 0; j < BOUNCES; j++)
-        {
-            RayHit hit = trace(ray);
-
-            pixel.xyz += ray.energy * shade(ray, hit);
-
-            if (length(ray.energy) < 0.001) break;
-        }
-    }
-    pixel.xyz /= SAMPLES;
-
+    // load data from first pass
     vec4 d = imageLoad(_g0, ivec2(gl_GlobalInvocationID.xy));
     float depth = d.w;
     vec3 normal = d.xyz*2.0-1.0; // unpack normal packaged into texture
 
+    // create a ray from the uv
+    Ray ray = createCameraRay(uv);
+    RayHit firstHit;
+    firstHit.position = ray.origin+ray.direction*depth;
+    firstHit.distance = depth;
+    firstHit.normal = normal;
+    firstHit.albedo = vec3(1.0,1.0,1.0);
+
+    // do a trace using precomputed depth and surface normal values
+    //RayHit hit = trace(ray);
+
+    // trace the rays path around the scene
+    for (int j = 1; j < BOUNCES; j++)
+    {
+        RayHit hit = trace(ray);
+
+        pixel.xyz += ray.energy * shade(ray, hit);
+
+        if (length(ray.energy) < 0.001) break;
+    }
+
+
     //pixel.xyz = mix(pixel.xyz, normal, 1.0-depth);
     pixel.xyz = mix(pixel.xyz, vec3(1.0), depth);
 
diff --git a/shader/root/rtpre.glsl b/shader/root/rtpre.glsl
index 793fc89..dd003f9 100644
--- a/shader/root/rtpre.glsl
+++ b/shader/root/rtpre.glsl
@@ -35,7 +35,7 @@ void main()
 
     // n roughly correlates to steepness of log curve
     // TODO: what does this mean in mathematical terms??
-    float n = 3;
+    float n = 1.0;
     float f = INF;
     float z = hit.distance;
     
diff --git a/src/main.c b/src/main.c
index ad29035..948666a 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,4 +1,3 @@
-
 #include "main.h"
 #include "gfx.h"
 #include "clock.h"
diff --git a/src/sphere.c b/src/sphere.c
index c2fd193..4503168 100644
--- a/src/sphere.c
+++ b/src/sphere.c
@@ -26,7 +26,7 @@ void makeSpheres(struct Sphere *spheres, int count)
     {
         x = 2.0*CGLM_PI * (float)i/(float)count;
         sc[0] = sin(x)*d;
-        sc[1] = sin(x*3.0-t);
+        sc[1] = sin(x*3.0-5.0*sin(t));
         sc[2] = cos(x)*d;
 
         float ic = i/(float)count*CGLM_PI*2.0;
diff --git a/todo.md b/todo.md
index 124baf3..6bb1bd2 100644
--- a/todo.md
+++ b/todo.md
@@ -14,10 +14,10 @@
         * [ ] do a 'fract
         * [-] depth
             * [x] acquire value
-        * [ ] acquire randomness
-        * [ ] acceleration time ! 
-            * [ ] auxiliary textures
-                * [ ] depth buffer
+        * [x] acquire randomness
+        * [-] acceleration time ! 
+            * [-] auxiliary textures
+                * [x] depth buffer
                 * [ ] frame blending
     * [ ] maybe do some fractals
         * [ ] mandelbrot