joejulian/gio
1
0
Fork 1
mirror of https://git.sr.ht/~eliasnaur/gio synced 2026-07-04 00:45:35 +00:00
Code Issues Packages Projects Releases Wiki Activity

gpu: implement automatic mipmaps for images

Browse Source 
All GPU APIs except OpenGL ES 2 can generate mipmaps for textures.
This trades 33% more GPU memory use for improved rendering quality
and speed for downscaled images.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
This commit is contained in:
Elias Naur
2022-10-22 11:04:22 -06:00
parent e69ef4f0b4
commit bebc73db37
19 changed files with 233 additions and 38 deletions
Download Patch File Download Diff File Expand all files Collapse all files
gpu/internal/opengl/opengl.go
+30 -7
View File
@@ -6,6 +6,7 @@ import (
"errors"
"fmt"
"image"
"math/bits"
"runtime"
"strings"
"time"
@@ -105,6 +106,7 @@ type texture struct {
triple textureTriple
width int
height int
mipmap bool
bindings driver.BufferBinding
foreign bool
}
@@ -695,13 +697,29 @@ func (b *Backend) NewTexture(format driver.TextureFormat, width, height int, min
return nil, errors.New("unsupported texture format")
}
b.BindTexture(0, tex)
b.funcs.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, toTexFilter(magFilter))
b.funcs.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, toTexFilter(minFilter))
min, mipmap := toTexFilter(minFilter)
mag, _ := toTexFilter(magFilter)
if b.gles && b.glver[0] < 3 {
// OpenGL ES 2 only supports mipmaps for power-of-two textures.
mipmap = false
}
tex.mipmap = mipmap
b.funcs.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, mag)
b.funcs.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, min)
b.funcs.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
b.funcs.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)
if b.gles && b.glver[0] >= 3 {
if mipmap {
nmipmaps := 1
if mipmap {
dim := width
if height > dim {
dim = height
}
log2 := 32 - bits.LeadingZeros32(uint32(dim)) - 1
nmipmaps = log2 + 1
}
// Immutable textures are required for BindImageTexture, and can't hurt otherwise.
b.funcs.TexStorage2D(gl.TEXTURE_2D, 1, tex.triple.internalFormat, width, height)
b.funcs.TexStorage2D(gl.TEXTURE_2D, nmipmaps, tex.triple.internalFormat, width, height)
} else {
b.funcs.TexImage2D(gl.TEXTURE_2D, 0, tex.triple.internalFormat, width, height, tex.triple.format, tex.triple.typ)
}
@@ -1195,12 +1213,14 @@ func (p *pipeline) Release() {
*p = pipeline{}
}
func toTexFilter(f driver.TextureFilter) int {
func toTexFilter(f driver.TextureFilter) (int, bool) {
switch f {
case driver.FilterNearest:
return gl.NEAREST
return gl.NEAREST, false
case driver.FilterLinear:
return gl.LINEAR
return gl.LINEAR, false
case driver.FilterLinearMipmapLinear:
return gl.LINEAR_MIPMAP_LINEAR, true
default:
panic("unsupported texture filter")
}
@@ -1234,6 +1254,9 @@ func (t *texture) Upload(offset, size image.Point, pixels []byte, stride int) {
}
t.backend.glstate.pixelStorei(t.backend.funcs, gl.UNPACK_ROW_LENGTH, rowLen)
t.backend.funcs.TexSubImage2D(gl.TEXTURE_2D, 0, offset.X, offset.Y, size.X, size.Y, t.triple.format, t.triple.typ, pixels)
if t.mipmap {
t.backend.funcs.GenerateMipmap(gl.TEXTURE_2D)
}
}
func (t *timer) Begin() {