@@ -3,6 +3,7 @@

     { "include": ["@<glm/ext/(matrix|vector)_(float|u?int).*>", "public",  "<glm/glm.hpp>",                   "public"] },

     { "symbol":  ["glm::lookAt",                                "public",  "<glm/ext/matrix_transform.hpp>",  "public"] },

     { "symbol":  ["glm::perspective",                           "public",  "<glm/ext/matrix_clip_space.hpp>", "public"] },

+    { "symbol":  ["glm::project",                               "public",  "<glm/ext/matrix_projection.hpp>", "public"] },

     { "symbol":  ["glm::unProject",                             "public",  "<glm/ext/matrix_projection.hpp>", "public"] },

     { "symbol":  ["glm::convertLinearToSRGB",                   "public",  "<glm/gtc/color_space.hpp>",       "public"] },

 ]

Binary files a/doc/output.tga and b/doc/output.tga differ

@@ -56,6 +56,7 @@ struct Trace

 {

     float    distance;

     Material material;

+    vec3     miss;

 };

 //// Circle

@@ -69,15 +70,20 @@ struct Circle

         auto const offs = center - ray.origin;

         auto const proj = dot(offs, ray.direction);

         if (proj < 0.0F) // Past.

-            return {infinity, {}};

+            return {infinity, {}, {}};

         auto const perp2 = dot(offs, offs) - proj * proj;

         auto const pene2 = radius * radius - perp2;

         if (pene2 < 0.0F) // Miss.

-            return {infinity, {}};

+        {

+            auto const poin = ray.point(proj);

+            auto const rati = 1.0F - radius * inversesqrt(perp2);

+            auto const miss = rati * (center - poin);

+            return {proj, material, miss};

+        }

         auto const dist = proj - sqrt(pene2);

         if (dist < 0.0F) // Inside.

-            return {infinity, {}};

-        return {dist, material};

+            return {infinity, {}, {}};

+        return {dist, material, vec3(0.0F)};

     }

 };

@@ -91,7 +97,7 @@ struct Scene

     Shapes   shapes;

     Trace trace(Ray const & ray) const

     {

-        auto nearest = Trace{infinity, background};

+        auto nearest = Trace{infinity, background, {}};

         for (auto const & shape : shapes)

         {

             auto const trace = shape.trace(ray);

@@ -122,6 +128,16 @@ struct Camera

         auto const direction = normalize(world.xyz() - position);

         return Ray{position, direction};

     }

+    vec2 project(uvec2 const & size, vec3 const & point) const

+    {

+        auto const aspect   = (float)size.x / (float)size.y;

+        auto const viewport = uvec4(0, 0, size);

+        auto const up       = vec3(0.0F, 1.0F, 0.0F);

+        auto const view     = glm::lookAt(position, target, up);

+        auto const proj     = glm::perspective(fovy, aspect, near, far);

+        auto const window   = glm::project(point, view, proj, viewport);

+        return window.xy();

+    }

 };

 //// ACES

@@ -220,6 +236,15 @@ int main(int argc, char const * argv[])

         {

             auto trace = scene.trace(ray);

             auto color = trace.material.color;

+            if (trace.miss != vec3(0.0F))

+            {

+                auto const point = ray.point(trace.distance);

+                auto const dist  = distance(

+                    camera.project(size, point),

+                    camera.project(size, point + trace.miss)

+                );

+                color.a *= 1.0F - clamp(dist, 0.0F, 1.0F);

+            }

             rgb   += color.rgb() * color.a * trans;

             trans *= 1.0F - color.a;

             if (trace.distance == infinity || trans == 0.0F)