mirror of
https://git.sr.ht/~eliasnaur/gio
synced 2026-07-01 15:45:38 +00:00
Elias Naur
3ae5a37c24
A recent change made the OpenGL functions an interface of the functions required for the implementation of GPU, a renderer for Gio operations. That allowed for running Gio on external systems where OpenGL is available. However, to allow for non-OpenGL flavored backends such as Vulkan, Metal and Direct3D, this change introduces Backend for the high-level operations required by GPU. This change also adds a concrete backend to package gl. Type Backend is a first cut heavily based on OpenGL. Future changes will add more backends, where the Backend interface quite possibly will need refinement. Signed-off-by: Elias Naur <mail@eliasnaur.com>
47 lines
873 B
Go
47 lines
873 B
Go
// SPDX-License-Identifier: Unlicense OR MIT
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package unsafe
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import (
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"reflect"
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"unsafe"
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)
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// BytesView returns a byte slice view of a slice.
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func BytesView(s interface{}) []byte {
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v := reflect.ValueOf(s)
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first := v.Index(0)
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sz := int(first.Type().Size())
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return *(*[]byte)(unsafe.Pointer(&reflect.SliceHeader{
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Data: uintptr(unsafe.Pointer((*reflect.SliceHeader)(unsafe.Pointer(first.UnsafeAddr())))),
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Len: v.Len() * sz,
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Cap: v.Cap() * sz,
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}))
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}
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// SliceOf returns a slice from a (native) pointer.
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func SliceOf(s uintptr) []byte {
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if s == 0 {
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return nil
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}
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sh := reflect.SliceHeader{
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Data: s,
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Len: 1 << 30,
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Cap: 1 << 30,
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}
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return *(*[]byte)(unsafe.Pointer(&sh))
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}
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// GoString convert a NUL-terminated C string
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// to a Go string.
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func GoString(s []byte) string {
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i := 0
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for {
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if s[i] == 0 {
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break
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}
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i++
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}
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return string(s[:i])
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}
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