| Name |
| |
| EXT_pixel_format_float |
| |
| Name Strings |
| |
| EGL_EXT_pixel_format_float |
| |
| Contributors |
| |
| Tom Cooksey |
| Jesse Hall |
| Mathias Heyer |
| Adam Jackson |
| James Jones |
| Daniel Koch |
| Jeff Leger |
| Weiwan Liu |
| Jeff Vigil |
| |
| Contact |
| |
| Weiwan Liu, NVIDIA (weiwliu 'at' nvidia.com) |
| |
| Status |
| |
| Complete |
| |
| Version |
| |
| Version 4 - Nov 22, 2016 |
| |
| Number |
| |
| EGL Extension #106 |
| |
| Dependencies |
| |
| This extension is written against the wording of the EGL 1.5 specification |
| (August 27, 2014). |
| |
| Overview |
| |
| This extensions aims to provide similar functionality as GL_ARB_color_- |
| buffer_float, WGL_ARB_pixel_format_float and GLX_ARB_fbconfig_float. This |
| extension allows exposing new EGLConfigs that support formats with |
| floating-point RGBA components. This is done by introducing a new EGLConfig |
| attribute that represents the component type, i.e. fixed-point or |
| floating-point. Such new EGLConfigs can be used to create floating-point |
| rendering surfaces and contexts. |
| |
| New Types |
| |
| None |
| |
| New Procedures and Functions |
| |
| None |
| |
| New Tokens |
| |
| Accepted as an attribute name in the <attrib_list> argument of |
| eglChooseConfig, and the <attribute> argument of eglGetConfigAttrib: |
| |
| EGL_COLOR_COMPONENT_TYPE_EXT 0x3339 |
| |
| Accepted as attribute values for the EGL_COLOR_COMPONENT_TYPE_EXT attribute |
| of eglChooseConfig: |
| |
| EGL_COLOR_COMPONENT_TYPE_FIXED_EXT 0x333A |
| EGL_COLOR_COMPONENT_TYPE_FLOAT_EXT 0x333B |
| |
| Additions to table 3.1, "EGLConfig attributes" in Section 3.4 "Configuration |
| Management": |
| |
| Attribute Type Notes |
| --------- ---- --------- |
| EGL_COLOR_COMPONENT_TYPE_EXT enum color component type |
| |
| Append one paragraph at the end of "The Color Buffer" section on page 21: |
| |
| EGL_COLOR_COMPONENT_TYPE_EXT indicates the color buffer component type, |
| and must be either EGL_COLOR_COMPONENT_TYPE_FIXED_EXT for fixed-point |
| color buffers, or EGL_COLOR_COMPONENT_TYPE_FLOAT_EXT for floating-point |
| color buffers. |
| |
| Add one entry to Table 3.4 and increment "Sort Priority" between "2" and |
| "11" by one for existing entries: |
| |
| Attribute Default |
| ----------- ------------ |
| EGL_COLOR_COMPONENT_TYPE_EXT EGL_COLOR_COMPONENT_TYPE_FIXED_EXT |
| |
| Selection Criteria Sort Order Priority |
| ------------------ ---------- -------- |
| Exact Special 2 |
| |
| Insert before the entry for EGL_COLOR_BUFFER_TYPE, and increment its |
| numbering and subsequent numbering by one: |
| |
| 2. Special: by EGL_COLOR_COMPONENT_TYPE_EXT where the precedence is |
| EGL_COLOR_COMPONENT_TYPE_FIXED_EXT, EGL_COLOR_COMPONENT_TYPE_FLOAT_EXT |
| |
| Change footnote 8 on page 30 to: |
| |
| Within the same EGL_COLOR_COMPONENT_TYPE_EXT, this rule places configs |
| with deeper color buffers first in the list returned by |
| eglChooseConfig... |
| |
| Issues |
| |
| 1. When reading from or rendering to a floating-point EGL surface, is there |
| any clamping performed on the values? |
| |
| RESOLVED: It depends on the behavior of the client API. For example, in |
| OpenGL and ES, by default no clamping will be done on the floating-point |
| values, unless the clamping behavior is changed via the client API. |
| |
| 2. When rendering to a floating-point EGL surface, since values may not be |
| clamped to [0, 1], what is the range of values that applications can use |
| to get display's "darkest black" and "brightest white"? |
| |
| RESOLVED: It is not in the scope of this extension to define a range of |
| values that corresponds to display's capability. Please refer to the EGL |
| specification for the chosen colorspace (EGL_GL_COLORSPACE), where such a |
| reference range may be defined. |
| |
| Revision History |
| |
| Rev. Date Author Changes |
| ---- -------- --------------- ------------------------------------------ |
| 1 12/11/15 Weiwan Liu Initial version |
| 2 05/18/16 Weiwan Liu Rename to EXT |
| 3 05/31/16 Weiwan Liu Add issues |
| 4 11/22/16 Weiwan Liu Change status to complete |
| |