Description
Flat-screen geometric gaze offsets from explicitly calibrated coordinates and viewing distance, not an eye-tracker calibration or diagnosis.
Vision research uses stimulus angles, chart notations, image scales, viewing distances, coordinate origins, and observation windows. These quantities have different denominators and measurement conventions. A conversion or support share does not independently establish a visual measurement or its clinical interpretation.
Flat-screen geometric gaze offsets from explicitly calibrated coordinates and viewing distance, not an eye-tracker calibration or diagnosis.
When to use this tool
Use Eye Tracker Screen Gaze Angle Term when you need this image, stimulus, notation, coordinate, or observation component for supplied research data.
How to use the tool and how it works
- Enter x, y, centerX, centerY, viewingDistance. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read horizontalRadians, verticalRadians, radialRadians. Use the output convention below.
For positive viewingDistance return horizontalRadians=atan2(x-centerX,distance), verticalRadians=atan2(y-centerY,distance), and radialRadians=atan2(hypot(x-centerX,y-centerY),distance).1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| x | X | Required. Finite number. |
| y | Y | Required. Finite number. |
| centerX | Center X | Required. Finite number. |
| centerY | Center Y | Required. Finite number. |
| viewingDistance | Viewing Distance | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| horizontalRadians | Horizontal Radians | Required. Finite number. |
| verticalRadians | Vertical Radians | Required. Finite number. |
| radialRadians | Radial Radians | Required. Finite number. |
{
"input": {
"x": 3,
"y": 4,
"centerX": 0,
"centerY": 0,
"viewingDistance": 10
},
"output": {
"horizontalRadians": 0.2914567944778671,
"verticalRadians": 0.3805063771123649,
"radialRadians": 0.4636476090008061
}
}Limitations and assumptions
- Screen coordinates and viewing distance need one physical length unit. The model assumes a flat screen and centered perpendicular viewing axis; head position, distortion, gaze calibration, and clinical visual function are not assessed.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use calibrated acquisition and a documented visual or imaging protocol for complete interpretation. Confirm the reporting notation, viewing geometry, image scale, and support of the underlying observations.
References
Similar or alternative tools
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