This extension allows an application to modify the locations of samples within a pixel used in multisample rasterization. Additionally, it allows applications to specify different sample locations for each pixel in a group of adjacent pixels, which may increase antialiasing quality (particularly if a custom resolve shader is used that takes advantage of these different locations).
It is common for implementations to optimize the storage of depth values by storing values that can be used to reconstruct depth at each sample location, rather than storing separate depth values for each sample. For example, the depth values from a single triangle can be represented using plane equations. When the depth value for a sample is needed, it is automatically evaluated at the sample location. Modifying the sample locations causes the reconstruction to no longer evaluate the same depth values as when the samples were originally generated. This extension provides a command to "evaluate" and store per-sample depth values using the currently programmed sample locations, which allows the application to manage this issue if/when necessary.
The programmable sample locations are used during rasterization and for evaluation of depth functions during normal geometric rendering. The programmable locations are associated with a framebuffer object rather than an individual depth buffer, so if the depth buffer is used as a texture the texture sampling may be done at the standard sample locations. Additionally, commands that do not render geometric primitives (e.g. ReadPixels, BlitFramebuffer, CopyTexSubImage2D, etc.) may use the standard sample locations to evaluate depth functions rather than the programmable locations. If a single depth buffer is used at different times with different sample locations, the depth functions may be interpreted using the current sample locations.
| Modifier and Type | Field and Description |
|---|---|
| public static final int | GL_FRAMEBUFFER_PROGRAMMABLE_SAMPLE_LOCATIONS_ARB
// Alias of SAMPLE_POSITION. |
| public static final int | GL_FRAMEBUFFER_SAMPLE_LOCATION_PIXEL_GRID_ARB
// Alias of SAMPLE_POSITION. |
| public static final int | GL_PROGRAMMABLE_SAMPLE_LOCATION_TABLE_SIZE_ARB
Accepted by the |
| public static final int | GL_SAMPLE_LOCATION_PIXEL_GRID_HEIGHT_ARB
Accepted by the |
| public static final int | GL_SAMPLE_LOCATION_PIXEL_GRID_WIDTH_ARB
Accepted by the |
| public static final int | GL_SAMPLE_LOCATION_SUBPIXEL_BITS_ARB
Accepted by the |
| Access | Constructor and Description |
|---|---|
| protected |
| Modifier and Type | Method and Description | |||
|---|---|---|---|---|
| public static native void | glEvaluateDepthValuesARB()
Evaluates depth values for all samples in the current depth buffer (subject to the pixel ownership and scissor tests) and stores each value in the depth buffer. | |||
| public static void | glFramebufferSampleLocationsfvARB(int
the framebuffer target. One of: target, int
the first sample location to update start, FloatBuffer a pair of values for each sample location to update v)Controls the programmable sample locations for the framebuffer bound to the specified | |||
| public static void | glFramebufferSampleLocationsfvARB(int target, int start, float[] v)
Array version of: | |||
| public static void | glNamedFramebufferSampleLocationsfvARB(int
the framebuffer object to update framebuffer, int the first sample location to update start, FloatBuffer a pair of values for each sample location to update v)DSA version of | |||
| public static void | glNamedFramebufferSampleLocationsfvARB(int framebuffer, int start, float[] v)
Array version of: | |||
| public static native void | nglFramebufferSampleLocationsfvARB(int target, int start, int
the number of sample locations to update count, long v)Unsafe version of: | |||
| public static native void | nglNamedFramebufferSampleLocationsfvARB(int framebuffer, int start, int
the number of sample locations to update count, long v)Unsafe version of: |
| GL_FRAMEBUFFER_PROGRAMMABLE_SAMPLE_LOCATIONS_ARB | back to summary |
|---|---|
| public static final int GL_FRAMEBUFFER_PROGRAMMABLE_SAMPLE_LOCATIONS_ARB // Alias of SAMPLE_POSITION. Before NV_expms, the spec used "location". SAMPLE_LOCATION_ARB 0x8E50 PROGRAMMABLE_SAMPLE_LOCATION_ARB 0x9341 Accepted by
the | |
| GL_FRAMEBUFFER_SAMPLE_LOCATION_PIXEL_GRID_ARB | back to summary |
|---|---|
| public static final int GL_FRAMEBUFFER_SAMPLE_LOCATION_PIXEL_GRID_ARB // Alias of SAMPLE_POSITION. Before NV_expms, the spec used "location". SAMPLE_LOCATION_ARB 0x8E50 PROGRAMMABLE_SAMPLE_LOCATION_ARB 0x9341 Accepted by
the | |
| GL_PROGRAMMABLE_SAMPLE_LOCATION_TABLE_SIZE_ARB | back to summary |
|---|---|
| public static final int GL_PROGRAMMABLE_SAMPLE_LOCATION_TABLE_SIZE_ARB Accepted by the | |
| GL_SAMPLE_LOCATION_PIXEL_GRID_HEIGHT_ARB | back to summary |
|---|---|
| public static final int GL_SAMPLE_LOCATION_PIXEL_GRID_HEIGHT_ARB Accepted by the | |
| GL_SAMPLE_LOCATION_PIXEL_GRID_WIDTH_ARB | back to summary |
|---|---|
| public static final int GL_SAMPLE_LOCATION_PIXEL_GRID_WIDTH_ARB Accepted by the | |
| GL_SAMPLE_LOCATION_SUBPIXEL_BITS_ARB | back to summary |
|---|---|
| public static final int GL_SAMPLE_LOCATION_SUBPIXEL_BITS_ARB Accepted by the | |
| ARBSampleLocations | back to summary |
|---|---|
| protected ARBSampleLocations() | |
| glEvaluateDepthValuesARB | back to summary |
|---|---|
| public static native void glEvaluateDepthValuesARB() Evaluates depth values for all samples in the current depth buffer (subject to the pixel ownership and scissor tests) and stores each value in the depth buffer. This can be used to ensure that later accesses will use depth values consistent with the sample locations used when the samples were generated. If the current framebuffer has no depth buffer, EvaluateDepthValuesARB will have no effect. | |
| glFramebufferSampleLocationsfvARB | back to summary | |||
|---|---|---|---|---|
| public static void glFramebufferSampleLocationsfvARB(int target, int start, FloatBuffer v) Controls the programmable sample locations for the framebuffer bound to the specified There are
| ||||
| glFramebufferSampleLocationsfvARB | back to summary |
|---|---|
| public static void glFramebufferSampleLocationsfvARB(int target, int start, float[] v) Array version of: | |
| glNamedFramebufferSampleLocationsfvARB | back to summary |
|---|---|
| public static void glNamedFramebufferSampleLocationsfvARB(int framebuffer, int start, FloatBuffer v) DSA version of
| |
| glNamedFramebufferSampleLocationsfvARB | back to summary |
|---|---|
| public static void glNamedFramebufferSampleLocationsfvARB(int framebuffer, int start, float[] v) Array version of: | |
| nglFramebufferSampleLocationsfvARB | back to summary |
|---|---|
| public static native void nglFramebufferSampleLocationsfvARB(int target, int start, int count, long v) Unsafe version of:
| |
| nglNamedFramebufferSampleLocationsfvARB | back to summary |
|---|---|
| public static native void nglNamedFramebufferSampleLocationsfvARB(int framebuffer, int start, int count, long v) Unsafe version of:
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