How do I know if my game has a graphics bug?

Look for visual glitches and whether they cluster on specific hardware. The direct sign is visual glitches players report or screenshot, things looking wrong (flickering, artifacts, missing or corrupted visuals, wrong colors), players often screenshot graphics bugs since they're visible. A telling sign is graphics problems clustering on specific GPUs or device types while other hardware is fine, since graphics bugs are frequently GPU- and driver-specific. And a sign is the game looking wrong on some players' hardware but fine on yours (you can't reproduce the glitch because it's specific to a GPU or driver you don't have). To diagnose, capture device and GPU context (with any associated crashes or errors) so you can see whether glitches cluster on specific hardware, and gather the player screenshots/reports (which show the glitch). If players report or screenshot visual glitches, problems cluster on specific GPUs/devices, or visuals are wrong on hardware you don't have, you have a graphics bug, often a hardware-specific one. The key is that graphics bugs are frequently GPU-specific (a rendering path that works on your GPU glitches on another), so they're invisible on your GPU but show in the device pattern of the affected hardware, capturing device/GPU context is what reveals the clustering (which GPUs glitch), which both confirms it's a graphics bug and points at the cause (a rendering issue on that GPU family). So you know your game has a graphics bug from the visual glitches (reported, screenshotted) and the hardware pattern (clustering on specific GPUs/devices, wrong on hardware you don't have), and the device/GPU context is key to diagnosing GPU-specific graphics bugs that are invisible on your machine.

Why do graphics look wrong on some devices but not others?

Because graphics rendering depends heavily on the GPU and its driver, and these vary significantly across devices, so rendering that works correctly on one GPU can glitch on another. GPUs from different vendors and generations, and different driver versions, implement graphics features and handle edge cases differently, and some have quirks or bugs of their own, so a rendering path, a shader, or a technique that relies on particular behavior (or on undefined or implementation-specific behavior) can produce correct results on your GPU and visual artifacts (flickering, corruption, missing elements, wrong colors) on another. Your development machine has one GPU and driver, so glitches specific to other hardware are invisible to you, they only appear on the GPUs and drivers you don't have, which is exactly why they're hard to catch and why they reach players. This hardware-specificity is why graphics look wrong on some devices but not others: the rendering behaves differently across GPUs/drivers, so a bug specific to a certain GPU or driver glitches on that hardware while your GPU (and others) render fine. To see and fix these GPU-specific graphics bugs, capture issues from the field with device and GPU context, which reveals the hardware pattern (which GPUs glitch), usually the key to diagnosing the bug (a glitch clustering on one GPU family points at a rendering issue specific to that hardware's behavior). So graphics look wrong on some devices but not others because rendering depends on the GPU/driver, which varies, so a rendering bug specific to a certain GPU/driver glitches there while your GPU renders correctly, invisible to you. The fix involves not relying on undefined or implementation-specific GPU behavior (so rendering is robust across GPUs), testing rendering on a range of real GPUs (to catch what you can), and capturing issues with device/GPU context from the field (to see the GPU-specific glitches on hardware you don't have, via the device pattern). The device/GPU context is essential, it's what makes a GPU-specific graphics bug, invisible on your GPU, into a findable problem by revealing which hardware glitches and pointing at the rendering cause.

How do I fix graphics bugs that don't appear on my machine?

Capture which devices/GPUs show the glitches from the field, use the device pattern to identify the cause, and fix the rendering for the affected hardware, since the bug is on a GPU you don't have. The bug doesn't appear on your machine because it's GPU- or driver-specific (on hardware you don't have), so you can't reproduce it directly, you have to work from the device pattern. Capture issues with device and GPU context from the field, so you can see which GPUs/devices show the glitch (the device pattern), since graphics bugs invisible on your GPU only show in the affected hardware's pattern, and gather player screenshots/reports (showing the glitch). Use the device pattern to identify the cause: a glitch clustering on a specific GPU family or driver version points at a rendering issue specific to that hardware's behavior (e.g. a shader or rendering technique that relies on behavior that GPU handles differently, or an undefined behavior that GPU exposes), so the affected hardware tells you where the problem is. Then fix the rendering for the affected hardware: make the rendering robust across GPUs (don't rely on undefined or implementation-specific behavior, handle the affected GPU's difference), which may involve adjusting the shader, technique, or rendering path so it works correctly on the affected hardware. If you can get access to a device with the affected GPU (or a similar one), reproducing the glitch there helps you fix and verify it; otherwise, you fix from the device pattern and player screenshots and verify in the field. Verify in the field: capture whether the glitch stops on the affected devices on the fixed version (device-filtered tracking), since you may not be able to confirm locally (you don't have the GPU). So you fix graphics bugs that don't appear on your machine by capturing which GPUs/devices glitch (from the field, since the bug is on hardware you don't have), using the device pattern to identify the cause (the affected GPU points at a rendering issue specific to it), fixing the rendering for the affected hardware (making it robust, handling the GPU's difference), and verifying in the field (the glitch stops on those devices). The key is that GPU-specific graphics bugs are invisible on your GPU, so you can't reproduce them directly, you work from the device pattern (which GPUs glitch, revealed by field capture with device/GPU context) and player screenshots to identify and fix the cause, then verify in the field. This turns a graphics bug you can't see on your machine into a fixable problem by using the real player data (device pattern, screenshots) the bug leaves on the affected hardware. Testing on a range of real GPUs before launch catches some, but since you can't own every GPU, field capture with device/GPU context is what lets you find and fix the GPU-specific graphics bugs that don't appear on your machine but do on your players'.

Signs Your Game Has a Graphics Bug

Quick answer: Watch for visual glitches players report or screenshot, flickering or artifacts, problems clustering on specific GPUs or devices, and visuals wrong on some hardware but not yours. Graphics bugs are often GPU-specific.

A graphics bug, visual glitches, flickering, artifacts, or corrupted rendering, hurts the quality of your game and is often specific to certain hardware. Here are the signs your game has a graphics bug.

Visual Glitches Players Report or Screenshot

The direct sign is visual glitches players report or screenshot, things looking wrong, flickering, artifacts, missing or corrupted visuals, wrong colors. Players often screenshot graphics bugs (they're visible), so reports and screenshots of visual problems are a direct sign of a graphics bug.

Bugnet captures crashes and context with device info, so GPU-related issues are identifiable. Visual glitches players report or screenshot are the direct sign, and capturing device/GPU context (with any associated crashes or errors) helps you see whether the glitches cluster on specific hardware, since graphics bugs are often GPU-specific, the device pattern is key to diagnosing them.

Problems Clustering on Specific GPUs or Devices

A telling sign is graphics problems clustering on specific GPUs or device types while other hardware is fine. Graphics bugs are frequently GPU- and driver-specific (a rendering path that works on one GPU glitches on another), so glitches concentrated on a GPU family or device point at a hardware-specific graphics bug.

Bugnet captures device and GPU context, so glitches clustering on specific hardware are identifiable. Problems clustering on specific GPUs or devices are a sign of a hardware-specific graphics bug, and the device/GPU context reveals the clustering (and points at the cause, a rendering issue on that GPU family), which is essential since graphics bugs invisible on your GPU only show in the device pattern of the affected hardware.

Visuals That Look Wrong on Some Hardware but Not Yours

A sign is the game looking wrong on some players' hardware but fine on yours, you can't reproduce the visual glitch because it's specific to a GPU or driver you don't have. If players report graphics problems you can't see on your machine, the bug is hardware-specific, on hardware outside your test set.

Bugnet captures device and GPU context from the field, so glitches on hardware you don't have are identifiable. Visuals wrong on some hardware but not yours is a sign of a GPU-specific graphics bug, and field capture with device/GPU context is how you see and diagnose it, since the bug is on a GPU you don't have, the device pattern (which GPUs glitch) is what reveals and helps fix it, even though you can't reproduce it yourself.

Watch for visual glitches players report or screenshot, flickering or artifacts, problems clustering on specific GPUs or devices, and visuals wrong on some hardware but not yours. Graphics bugs are often GPU-specific.