initialize a callback-based context

initialize a memory-decode context

For perf reasons this code is duplicated in stbir__resample_horizontal_upsample/downsample, if you change it here change it there too.

Attempt to load but when missing, return NULL instead of FallbackGlyph

Helpers

Start packing over current empty texture

Keep source/input FontData

Backend data stored in io.BackendPlatformUserData to allow support for multiple Dear ImGui contexts It is STRONGLY preferred that you use docking bran

当前是否存在操作焦点窗口（若存在，则一定是活窗口）

Resize a vector to a smaller size, guaranteed not to cause a reallocation

Compilers should be able to optimize this into the ror instruction.

return true logging is enabled for the given level.

returns 1 if the product is valid, 0 on overflow. negative factors are considered invalid.

Get the specified scan line from the ring buffer.

Computes 128-bit result of multiplication of two 64-bit unsigned integers.

Those functions are not inlined in imgui_internal.h, allowing us to hide ImStbTexteditState from that header.

提取指定模块中的资源文件