# CategoryPixels SDL offers facilities for pixel management. Largely these facilities deal with pixel _format_: what does this set of bits represent? If you mostly want to think of a pixel as some combination of red, green, blue, and maybe alpha intensities, this is all pretty straightforward, and in many cases, is enough information to build a perfectly fine game. However, the actual definition of a pixel is more complex than that: Pixels are a representation of a color in a particular color space. The first characteristic of a color space is the color type. SDL understands two different color types, RGB and YCbCr, or in SDL also referred to as YUV. RGB colors consist of red, green, and blue channels of color that are added together to represent the colors we see on the screen. https://en.wikipedia.org/wiki/RGB_color_model YCbCr colors represent colors as a Y luma brightness component and red and blue chroma color offsets. This color representation takes advantage of the fact that the human eye is more sensitive to brightness than the color in an image. The Cb and Cr components are often compressed and have lower resolution than the luma component. https://en.wikipedia.org/wiki/YCbCr When the color information in YCbCr is compressed, the Y pixels are left at full resolution and each Cr and Cb pixel represents an average of the color information in a block of Y pixels. The chroma location determines where in that block of pixels the color information is coming from. The color range defines how much of the pixel to use when converting a pixel into a color on the display. When the full color range is used, the entire numeric range of the pixel bits is significant. When narrow color range is used, for historical reasons, the pixel uses only a portion of the numeric range to represent colors. The color primaries and white point are a definition of the colors in the color space relative to the standard XYZ color space. https://en.wikipedia.org/wiki/CIE_1931_color_space The transfer characteristic, or opto-electrical transfer function (OETF), is the way a color is converted from mathematically linear space into a non-linear output signals. https://en.wikipedia.org/wiki/Rec._709#Transfer_characteristics The matrix coefficients are used to convert between YCbCr and RGB colors. <!-- END CATEGORY DOCUMENTATION --> ## Functions <!-- DO NOT HAND-EDIT CATEGORY LISTS, THEY ARE AUTOGENERATED AND WILL BE OVERWRITTEN, BASED ON TAGS IN INDIVIDUAL PAGE FOOTERS. EDIT THOSE INSTEAD. --> <!-- BEGIN CATEGORY LIST: CategoryPixels, CategoryAPIFunction --> - [SDL_CreatePalette](SDL_CreatePalette) - [SDL_DestroyPalette](SDL_DestroyPalette) - [SDL_GetMasksForPixelFormat](SDL_GetMasksForPixelFormat) - [SDL_GetPixelFormatDetails](SDL_GetPixelFormatDetails) - [SDL_GetPixelFormatForMasks](SDL_GetPixelFormatForMasks) - [SDL_GetPixelFormatName](SDL_GetPixelFormatName) - [SDL_GetRGB](SDL_GetRGB) - [SDL_GetRGBA](SDL_GetRGBA) - [SDL_MapRGB](SDL_MapRGB) - [SDL_MapRGBA](SDL_MapRGBA) - [SDL_MapSurfaceRGB](SDL_MapSurfaceRGB) - [SDL_MapSurfaceRGBA](SDL_MapSurfaceRGBA) - [SDL_SetPaletteColors](SDL_SetPaletteColors) <!-- END CATEGORY LIST --> ## Datatypes <!-- DO NOT HAND-EDIT CATEGORY LISTS, THEY ARE AUTOGENERATED AND WILL BE OVERWRITTEN, BASED ON TAGS IN INDIVIDUAL PAGE FOOTERS. EDIT THOSE INSTEAD. --> <!-- BEGIN CATEGORY LIST: CategoryPixels, CategoryAPIDatatype --> - (none.) <!-- END CATEGORY LIST --> ## Structs <!-- DO NOT HAND-EDIT CATEGORY LISTS, THEY ARE AUTOGENERATED AND WILL BE OVERWRITTEN, BASED ON TAGS IN INDIVIDUAL PAGE FOOTERS. EDIT THOSE INSTEAD. --> <!-- BEGIN CATEGORY LIST: CategoryPixels, CategoryAPIStruct --> - [SDL_Color](SDL_Color) - [SDL_FColor](SDL_FColor) - [SDL_Palette](SDL_Palette) - [SDL_PixelFormatDetails](SDL_PixelFormatDetails) <!-- END CATEGORY LIST --> ## Enums <!-- DO NOT HAND-EDIT CATEGORY LISTS, THEY ARE AUTOGENERATED AND WILL BE OVERWRITTEN, BASED ON TAGS IN INDIVIDUAL PAGE FOOTERS. EDIT THOSE INSTEAD. --> <!-- BEGIN CATEGORY LIST: CategoryPixels, CategoryAPIEnum --> - [SDL_ArrayOrder](SDL_ArrayOrder) - [SDL_BitmapOrder](SDL_BitmapOrder) - [SDL_ChromaLocation](SDL_ChromaLocation) - [SDL_ColorPrimaries](SDL_ColorPrimaries) - [SDL_ColorRange](SDL_ColorRange) - [SDL_Colorspace](SDL_Colorspace) - [SDL_ColorType](SDL_ColorType) - [SDL_MatrixCoefficients](SDL_MatrixCoefficients) - [SDL_PackedLayout](SDL_PackedLayout) - [SDL_PackedOrder](SDL_PackedOrder) - [SDL_PixelFormat](SDL_PixelFormat) - [SDL_PixelType](SDL_PixelType) - [SDL_TransferCharacteristics](SDL_TransferCharacteristics) <!-- END CATEGORY LIST --> ## Macros <!-- DO NOT HAND-EDIT CATEGORY LISTS, THEY ARE AUTOGENERATED AND WILL BE OVERWRITTEN, BASED ON TAGS IN INDIVIDUAL PAGE FOOTERS. EDIT THOSE INSTEAD. --> <!-- BEGIN CATEGORY LIST: CategoryPixels, CategoryAPIMacro --> - [SDL_ALPHA_OPAQUE](SDL_ALPHA_OPAQUE) - [SDL_ALPHA_OPAQUE_FLOAT](SDL_ALPHA_OPAQUE_FLOAT) - [SDL_ALPHA_TRANSPARENT](SDL_ALPHA_TRANSPARENT) - [SDL_ALPHA_TRANSPARENT_FLOAT](SDL_ALPHA_TRANSPARENT_FLOAT) - [SDL_BITSPERPIXEL](SDL_BITSPERPIXEL) - [SDL_BYTESPERPIXEL](SDL_BYTESPERPIXEL) - [SDL_COLORSPACECHROMA](SDL_COLORSPACECHROMA) - [SDL_COLORSPACEMATRIX](SDL_COLORSPACEMATRIX) - [SDL_COLORSPACEPRIMARIES](SDL_COLORSPACEPRIMARIES) - [SDL_COLORSPACERANGE](SDL_COLORSPACERANGE) - [SDL_COLORSPACETRANSFER](SDL_COLORSPACETRANSFER) - [SDL_COLORSPACETYPE](SDL_COLORSPACETYPE) - [SDL_DEFINE_COLORSPACE](SDL_DEFINE_COLORSPACE) - [SDL_DEFINE_PIXELFORMAT](SDL_DEFINE_PIXELFORMAT) - [SDL_DEFINE_PIXELFOURCC](SDL_DEFINE_PIXELFOURCC) - [SDL_ISCOLORSPACE_FULL_RANGE](SDL_ISCOLORSPACE_FULL_RANGE) - [SDL_ISCOLORSPACE_LIMITED_RANGE](SDL_ISCOLORSPACE_LIMITED_RANGE) - [SDL_ISCOLORSPACE_MATRIX_BT2020_NCL](SDL_ISCOLORSPACE_MATRIX_BT2020_NCL) - [SDL_ISCOLORSPACE_MATRIX_BT601](SDL_ISCOLORSPACE_MATRIX_BT601) - [SDL_ISCOLORSPACE_MATRIX_BT709](SDL_ISCOLORSPACE_MATRIX_BT709) - [SDL_ISPIXELFORMAT_10BIT](SDL_ISPIXELFORMAT_10BIT) - [SDL_ISPIXELFORMAT_ALPHA](SDL_ISPIXELFORMAT_ALPHA) - [SDL_ISPIXELFORMAT_ARRAY](SDL_ISPIXELFORMAT_ARRAY) - [SDL_ISPIXELFORMAT_FLOAT](SDL_ISPIXELFORMAT_FLOAT) - [SDL_ISPIXELFORMAT_FOURCC](SDL_ISPIXELFORMAT_FOURCC) - [SDL_ISPIXELFORMAT_INDEXED](SDL_ISPIXELFORMAT_INDEXED) - [SDL_ISPIXELFORMAT_PACKED](SDL_ISPIXELFORMAT_PACKED) - [SDL_PIXELFLAG](SDL_PIXELFLAG) - [SDL_PIXELLAYOUT](SDL_PIXELLAYOUT) - [SDL_PIXELORDER](SDL_PIXELORDER) - [SDL_PIXELTYPE](SDL_PIXELTYPE) <!-- END CATEGORY LIST --> ---- [CategoryAPICategory](CategoryAPICategory)