more shaders and updates/changes

shaders/video-plane-3d/shader.json

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+{
+  "id": "video-plane-3d",
+  "name": "Video Plane 3D",
+  "description": "Places the video on a perspective 2D plane in 3D space with camera FOV, XYZ position, and pan/tilt/roll controls.",
+  "category": "Projection",
+  "entryPoint": "shadeVideo",
+  "parameters": [
+    {
+      "id": "fovDegrees",
+      "label": "FOV",
+      "type": "float",
+      "default": 45,
+      "min": 5,
+      "max": 150,
+      "step": 0.1,
+      "description": "Virtual camera vertical field of view in degrees."
+    },
+    {
+      "id": "positionX",
+      "label": "X",
+      "type": "float",
+      "default": 0,
+      "min": -4,
+      "max": 4,
+      "step": 0.01,
+      "description": "Horizontal plane position in world units."
+    },
+    {
+      "id": "positionY",
+      "label": "Y",
+      "type": "float",
+      "default": 0,
+      "min": -4,
+      "max": 4,
+      "step": 0.01,
+      "description": "Vertical plane position in world units."
+    },
+    {
+      "id": "positionZ",
+      "label": "Z",
+      "type": "float",
+      "default": 2.2,
+      "min": 0.1,
+      "max": 10,
+      "step": 0.01,
+      "description": "Depth of the plane in front of the virtual camera."
+    },
+    {
+      "id": "panDegrees",
+      "label": "Pan",
+      "type": "float",
+      "default": 0,
+      "min": -180,
+      "max": 180,
+      "step": 0.1,
+      "description": "Rotates the plane left/right around its vertical axis."
+    },
+    {
+      "id": "tiltDegrees",
+      "label": "Tilt",
+      "type": "float",
+      "default": 0,
+      "min": -120,
+      "max": 120,
+      "step": 0.1,
+      "description": "Rotates the plane up/down around its horizontal axis."
+    },
+    {
+      "id": "rollDegrees",
+      "label": "Roll",
+      "type": "float",
+      "default": 0,
+      "min": -180,
+      "max": 180,
+      "step": 0.1,
+      "description": "Rotates the plane around its face normal."
+    },
+    {
+      "id": "planeScale",
+      "label": "Plane Scale",
+      "type": "float",
+      "default": 1.4,
+      "min": 0.05,
+      "max": 6,
+      "step": 0.01,
+      "description": "Height of the video plane in world units; width follows the source aspect ratio."
+    },
+    {
+      "id": "edgeFeather",
+      "label": "Edge Feather",
+      "type": "float",
+      "default": 1.5,
+      "min": 0,
+      "max": 24,
+      "step": 0.1,
+      "description": "Softens the plane edge in source pixels."
+    },
+    {
+      "id": "backgroundMix",
+      "label": "Background Mix",
+      "type": "float",
+      "default": 0,
+      "min": 0,
+      "max": 1,
+      "step": 0.01,
+      "description": "Mixes the original video behind the projected plane."
+    },
+    {
+      "id": "outsideColor",
+      "label": "Outside Color",
+      "type": "color",
+      "default": [
+        0,
+        0,
+        0,
+        1
+      ],
+      "description": "Color used where the camera ray misses the plane."
+    }
+  ]
+}

shaders/video-plane-3d/shader.slang

@@ -0,0 +1,84 @@
+static const float PI = 3.14159265358979323846;
+
+float radiansFromDegrees(float degrees)
+{
+	return degrees * (PI / 180.0);
+}
+
+float3 rotateX(float3 p, float angle)
+{
+	float s = sin(angle);
+	float c = cos(angle);
+	return float3(p.x, c * p.y - s * p.z, s * p.y + c * p.z);
+}
+
+float3 rotateY(float3 p, float angle)
+{
+	float s = sin(angle);
+	float c = cos(angle);
+	return float3(c * p.x + s * p.z, p.y, -s * p.x + c * p.z);
+}
+
+float3 rotateZ(float3 p, float angle)
+{
+	float s = sin(angle);
+	float c = cos(angle);
+	return float3(c * p.x - s * p.y, s * p.x + c * p.y, p.z);
+}
+
+float3 rotateWorldToPlane(float3 value)
+{
+	float pan = radiansFromDegrees(panDegrees);
+	float tilt = radiansFromDegrees(tiltDegrees);
+	float roll = radiansFromDegrees(rollDegrees);
+	return rotateZ(rotateX(rotateY(value, -pan), -tilt), -roll);
+}
+
+float planeEdgeMask(float2 uv, float2 inputResolution)
+{
+	float2 feather = max(edgeFeather, 0.0) / max(inputResolution, float2(1.0, 1.0));
+	feather = max(feather, float2(0.00001, 0.00001));
+
+	float left = smoothstep(0.0, feather.x, uv.x);
+	float right = 1.0 - smoothstep(1.0 - feather.x, 1.0, uv.x);
+	float top = smoothstep(0.0, feather.y, uv.y);
+	float bottom = 1.0 - smoothstep(1.0 - feather.y, 1.0, uv.y);
+	return saturate(left * right * top * bottom);
+}
+
+float4 shadeVideo(ShaderContext context)
+{
+	float2 outputResolution = max(context.outputResolution, float2(1.0, 1.0));
+	float outputAspect = outputResolution.x / outputResolution.y;
+	float sourceAspect = context.inputResolution.x / max(context.inputResolution.y, 1.0);
+	float tanHalfFov = tan(radiansFromDegrees(clamp(fovDegrees, 5.0, 150.0)) * 0.5);
+
+	float2 screen = float2(context.uv.x * 2.0 - 1.0, 1.0 - context.uv.y * 2.0);
+	float3 rayOrigin = float3(0.0, 0.0, 0.0);
+	float3 rayDirection = normalize(float3(screen.x * outputAspect * tanHalfFov, screen.y * tanHalfFov, 1.0));
+
+	float3 planePosition = float3(positionX, positionY, max(positionZ, 0.001));
+	float3 localOrigin = rotateWorldToPlane(rayOrigin - planePosition);
+	float3 localDirection = rotateWorldToPlane(rayDirection);
+
+	float backgroundAmount = saturate(backgroundMix);
+	float4 background = float4(lerp(outsideColor.rgb, context.sourceColor.rgb, backgroundAmount), 1.0);
+	if (abs(localDirection.z) < 0.00001)
+		return background;
+
+	float hitDistance = -localOrigin.z / localDirection.z;
+	if (hitDistance <= 0.0)
+		return background;
+
+	float3 localHit = localOrigin + localDirection * hitDistance;
+	float halfHeight = max(planeScale, 0.001) * 0.5;
+	float halfWidth = halfHeight * sourceAspect;
+	float2 planeUv = float2(
+		localHit.x / max(halfWidth * 2.0, 0.0001) + 0.5,
+		0.5 - localHit.y / max(halfHeight * 2.0, 0.0001)
+	);
+
+	float mask = planeEdgeMask(planeUv, max(context.inputResolution, float2(1.0, 1.0)));
+	float4 planeColor = sampleVideo(clamp(planeUv, 0.0, 1.0));
+	return saturate(lerp(background, planeColor, mask));
+}