1 files changed, 119 insertions, 0 deletions
diff --git a/src/aliasing/supersample.cpp b/src/aliasing/supersample.cpp
new file mode 100644
index 0000000..aa8e9d3
--- /dev/null
+++ b/src/aliasing/supersample.cpp
@@ -0,0 +1,119 @@
+#include "raytracer/raytracer.h"
+
+/**
+ * Extra credit -> Super Sampling
+ */
+
+const float SUPERSAMPLE_DISTANCE_FROM_CENTER = .25f; // note: max of .5f, unless overlapping with other pixels
+bool SUPER_SAMPLE = false;
+bool ADAPTIVE_SUPER_SAMPLING = false;
+
+RGBA RayTracer::superSample(
+        glm::vec4 eyeCamera,
+        glm::vec4 pixelDirCamera,
+        const RayTraceScene &scene) {
+    // get the color value at value between center and four corners
+    float x_delta = SUPERSAMPLE_DISTANCE_FROM_CENTER / (scene.width());
+    float y_delta = SUPERSAMPLE_DISTANCE_FROM_CENTER / (scene.height());
+    // TL == TOP LEFT
+    // BR = BOTTOM RIGHT, not Battle Royale :)
+    glm::vec4 pixelTL = getPixelFromRay(
+            eyeCamera,
+            glm::vec4(pixelDirCamera.x - x_delta, pixelDirCamera.y - y_delta, pixelDirCamera.z, 0.f),
+            scene);
+    glm::vec4 pixelTR = getPixelFromRay(
+            eyeCamera,
+            glm::vec4(pixelDirCamera.x + x_delta, pixelDirCamera.y - y_delta, pixelDirCamera.z, 0.f),
+            scene);
+    glm::vec4 pixelBL = getPixelFromRay(
+            eyeCamera,
+            glm::vec4(pixelDirCamera.x - x_delta, pixelDirCamera.y + y_delta, pixelDirCamera.z, 0.f),
+            scene);
+    glm::vec4 pixelBR = getPixelFromRay(
+            eyeCamera,
+            glm::vec4(pixelDirCamera.x + x_delta, pixelDirCamera.y + y_delta, pixelDirCamera.z, 0.f),
+            scene);
+
+    if (!ADAPTIVE_SUPER_SAMPLING) {
+        return toRGBA((pixelTL + pixelTR + pixelBL + pixelBR) / 4.f);
+    }
+
+    // ADAPTIVE SUPER SAMPLING
+    // make the region from the center of pixel smaller until we hit something
+    RGBA nohit = {0, 0, 0, 0}; // just here to say that a is 0 if no hit...
+    float TRAVERSE_DISTANCE = .025f;
+    float num_pixels = 4.f;
+    if (pixelTL.a == 0) {
+        num_pixels--;
+        float smallerDist = SUPERSAMPLE_DISTANCE_FROM_CENTER - TRAVERSE_DISTANCE;
+        while (smallerDist < TRAVERSE_DISTANCE) {
+            float x_delta = smallerDist / (scene.width());
+            float y_delta = smallerDist / (scene.height());
+            pixelTL = getPixelFromRay(
+                    eyeCamera,
+                    glm::vec4(pixelDirCamera.x - x_delta, pixelDirCamera.y - y_delta, pixelDirCamera.z, 0.f),
+                    scene);
+            if (pixelTL.a != 0) {
+                num_pixels++;
+                break;
+            }
+            smallerDist -= TRAVERSE_DISTANCE;
+        }
+    }
+    if (pixelTR.a == 0) {
+        num_pixels--;
+        float smallerDist = SUPERSAMPLE_DISTANCE_FROM_CENTER - TRAVERSE_DISTANCE;
+        while (smallerDist < TRAVERSE_DISTANCE) {
+            float x_delta = smallerDist / (scene.width());
+            float y_delta = smallerDist / (scene.height());
+            pixelTR = getPixelFromRay(
+                    eyeCamera,
+                    glm::vec4(pixelDirCamera.x - x_delta, pixelDirCamera.y - y_delta, pixelDirCamera.z, 0.f),
+                    scene);
+            if (pixelTR.a != 0) {
+                num_pixels += 1;
+                break;
+            }
+            smallerDist -= TRAVERSE_DISTANCE;
+        }
+    }
+    if (pixelBL.a == 0) {
+        num_pixels--;
+        float smallerDist = SUPERSAMPLE_DISTANCE_FROM_CENTER - TRAVERSE_DISTANCE;
+        while (smallerDist < TRAVERSE_DISTANCE) {
+            float x_delta = smallerDist / (scene.width());
+            float y_delta = smallerDist / (scene.height());
+            pixelBL = getPixelFromRay(
+                    eyeCamera,
+                    glm::vec4(pixelDirCamera.x - x_delta, pixelDirCamera.y - y_delta, pixelDirCamera.z, 0.f),
+                    scene);
+            if (pixelBL.a != 0) {
+                num_pixels += 1;
+                break;
+            }
+            smallerDist -= TRAVERSE_DISTANCE;
+        }
+    }
+    if (pixelBR.a == 0) {
+        num_pixels--;
+        float smallerDist = SUPERSAMPLE_DISTANCE_FROM_CENTER - TRAVERSE_DISTANCE;
+        while (smallerDist < TRAVERSE_DISTANCE) {
+            float x_delta = smallerDist / (scene.width());
+            float y_delta = smallerDist / (scene.height());
+            pixelBR = getPixelFromRay(
+                    eyeCamera,
+                    glm::vec4(pixelDirCamera.x - x_delta, pixelDirCamera.y - y_delta, pixelDirCamera.z, 0.f),
+                    scene);
+            if (pixelBR.a != 0) {
+                num_pixels += 1;
+                break;
+            }
+            smallerDist -= TRAVERSE_DISTANCE;
+        }
+    }
+
+    if (num_pixels == 0.f) {
+        return nohit;
+    }
+    return toRGBA((pixelTL + pixelTR + pixelBL + pixelBR) / num_pixels);
+}