[depth of field] fixed an oultine bug

data/shaders/depth_of_field.hlsl

@@ -24,29 +24,23 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 //====================
 
 // constants
-static const float BLUR_RADIUS                = 10.0f; // maximum radius of the blur
-static const float BASE_FOCAL_LENGTH          = 50.0;  // in mm, base focal length
-static const float SENSOR_HEIGHT              = 24.0;  // in mm, assuming full-frame sensor
-static const float EDGE_DETECTION_THRESHOLD   = 0.1f;  // adjust to control edge sensitivity
+static const float BLUR_RADIUS                = 10.0f;  // maximum radius of the blur
+static const float BASE_FOCAL_LENGTH          = 50.0;   // in mm, base focal length
+static const float SENSOR_HEIGHT              = 24.0;   // in mm, assuming full-frame sensor
+static const float EDGE_DETECTION_THRESHOLD   = 0.001f; // adjust to control edge sensitivity
 static const uint  AVERAGE_DEPTH_SAMPLE_COUNT = 10;
-static const float AVERAGE_DEPTH_RADIUS       = 0.1f;
+static const float AVERAGE_DEPTH_RADIUS       = 0.5f;
 
-float compute_coc(float2 uv, float focus_distance, float aperture)
+float compute_coc(float2 uv, float2 texel_size, float2 resolution, float focus_distance, float aperture)
 {
-    float2 resolution_out;
-    tex_uav.GetDimensions(resolution_out.x, resolution_out.y);
-    float2 texel_size = 1.0 / resolution_out;
-    float depth       = get_linear_depth(uv);
+    float depth = get_linear_depth(uv);
 
     // edge detection
     float depth_diff = 0;
     for (int i = -1; i <= 1; i++)
     {
         for (int j = -1; j <= 1; j++)
         {
-            if (i == 0 && j == 0)
-                continue;
-
             float2 offset         = float2(i, j) * texel_size;
             float neighbor_depth  = get_linear_depth(uv + offset);
             depth_diff           += abs(depth - neighbor_depth);
@@ -65,7 +59,7 @@ float compute_coc(float2 uv, float focus_distance, float aperture)
     float coc_diameter = abs(aperture * (s2 - s1) * f) / (s2 * (s1 - f));
 
     // convert the diameter to pixels
-    float coc_pixels = coc_diameter * (resolution_out.y / SENSOR_HEIGHT);
+    float coc_pixels = coc_diameter * (resolution.y / SENSOR_HEIGHT);
 
     // adjust coc based on focus distance to enhance the effect
     float distance_factor  = saturate(focus_distance / 50.0);
@@ -82,14 +76,13 @@ float gaussian_weight(float x, float sigma)
     return exp(-0.5 * (x * x) / (sigma * sigma)) / (sigma * sqrt(2.0 * 3.14159265));
 }
 
-float3 gaussian_blur(float2 uv, float coc, float2 resolution_out)
+float3 gaussian_blur(float2 uv, float coc, float2 texel_size)
 {
-    float2 texel_size = 1.0f / resolution_out;
-    float sigma       = max(1.0, coc * BLUR_RADIUS);
-    int samples       = clamp(int(sigma * 0.5), 1, BLUR_RADIUS); // adaptive sampling
+    float sigma = max(1.0, coc * BLUR_RADIUS);
+    int samples = clamp(int(sigma * 0.5), 1, BLUR_RADIUS); // adaptive sampling
 
-    float3 color      = 0.0f;
-    float total_weight = 0.0;
+    float3 color       = 0.0f;
+    float total_weight = FLT_MIN;
     for (int i = -samples; i <= samples; i++)
     {
         for (int j = -samples; j <= samples; j++)
@@ -100,13 +93,13 @@ float3 gaussian_blur(float2 uv, float coc, float2 resolution_out)
             if (distance <= sigma)
             {
                 float weight  = gaussian_weight(distance, sigma);
-                color        += tex.Sample(samplers[sampler_bilinear_clamp], uv + offset).rgb * weight;
+                color        += tex.SampleLevel(samplers[sampler_bilinear_clamp], uv + offset, 0.0f).rgb * weight;
                 total_weight += weight;
             }
         }
     }
 
-    return color / (total_weight + FLT_MIN); 
+    return color / total_weight; 
 }
 
 float get_average_depth_circle(float2 center, float2 resolution_out)
@@ -129,17 +122,18 @@ float get_average_depth_circle(float2 center, float2 resolution_out)
 [numthreads(THREAD_GROUP_COUNT_X, THREAD_GROUP_COUNT_Y, 1)]
 void main_cs(uint3 thread_id : SV_DispatchThreadID)
 {
-    float2 resolution_out;
-    tex_uav.GetDimensions(resolution_out.x, resolution_out.y);
-    const float2 uv = (thread_id.xy + 0.5f) / resolution_out;
-
+    float2 resolution;
+    tex_uav.GetDimensions(resolution.x, resolution.y);
+    const float2 uv         = (thread_id.xy + 0.5f) / resolution;
+    const float2 texel_size = 1.0 / resolution;
+
     // get focal depth from camera
-    float focal_depth = get_average_depth_circle(float2(0.5, 0.5f), resolution_out);
+    float focal_depth = get_average_depth_circle(float2(0.5, 0.5f), resolution);
     float aperture    = pass_get_f3_value().x;
 
     // do the actual blurring
-    float coc             = compute_coc(uv, focal_depth, aperture);
-    float3 blurred_color  = gaussian_blur(uv, coc, resolution_out);
+    float coc             = compute_coc(uv, texel_size, resolution, focal_depth, aperture);
+    float3 blurred_color  = gaussian_blur(uv, coc, texel_size);
     float4 original_color = tex[thread_id.xy];
     float3 final_color    = lerp(original_color.rgb, blurred_color, coc);