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Abstract glyph renderer
This commit is contained in:
bloeys
156
glyphs/font_atlas.go
Executable file
156
glyphs/font_atlas.go
Executable file
@ -0,0 +1,156 @@
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package glyphs
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import (
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"image"
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"image/draw"
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"image/png"
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"math"
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"os"
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"github.com/bloeys/nterm/assert"
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"github.com/golang/freetype/truetype"
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"golang.org/x/image/font"
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"golang.org/x/image/math/fixed"
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)
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type FontAtlas struct {
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Font *truetype.Font
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Img *image.RGBA
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Glyphs map[rune]FontAtlasGlyph
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LineHeight int
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}
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type FontAtlasGlyph struct {
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U float32
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V float32
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SizeU float32
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SizeV float32
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Ascent float32
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Descent float32
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Advance float32
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}
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func NewFontAtlasFromFile(fontFile string, fontOptions *truetype.Options) (*FontAtlas, error) {
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fBytes, err := os.ReadFile(fontFile)
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if err != nil {
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return nil, err
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}
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f, err := truetype.Parse(fBytes)
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if err != nil {
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return nil, err
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}
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face := truetype.NewFace(f, fontOptions)
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atlas := NewFontAtlasFromFont(f, face, uint(fontOptions.Size))
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return atlas, nil
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}
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func NewFontAtlasFromFont(f *truetype.Font, face font.Face, pointSize uint) *FontAtlas {
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const maxAtlasSize = 8192
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glyphs := getGlyphsFromRanges(getGlyphRanges(f))
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assert.T(len(glyphs) > 0, "no glyphs")
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//Choose atlas size
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atlasSizeX := 512
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atlasSizeY := 512
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_, charWidthFixed, _ := face.GlyphBounds(glyphs[0])
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charWidth := charWidthFixed.Floor()
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lineHeight := face.Metrics().Height.Floor()
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maxLinesInAtlas := atlasSizeY/lineHeight - 1
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charsPerLine := atlasSizeX / charWidth
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linesNeeded := int(math.Ceil(float64(len(glyphs)) / float64(charsPerLine)))
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for linesNeeded > maxLinesInAtlas {
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atlasSizeX *= 2
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atlasSizeY *= 2
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maxLinesInAtlas = atlasSizeY/lineHeight - 1
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charsPerLine = atlasSizeX / charWidth
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linesNeeded = int(math.Ceil(float64(len(glyphs)) / float64(charsPerLine)))
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}
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assert.T(atlasSizeX <= maxAtlasSize, "Atlas size went beyond maximum")
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//Create atlas
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atlas := &FontAtlas{
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Font: f,
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Img: image.NewRGBA(image.Rect(0, 0, atlasSizeX, atlasSizeY)),
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Glyphs: make(map[rune]FontAtlasGlyph, len(glyphs)),
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LineHeight: lineHeight,
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}
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//Clear background to black
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draw.Draw(atlas.Img, atlas.Img.Bounds(), image.Black, image.Point{}, draw.Src)
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drawer := &font.Drawer{
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Dst: atlas.Img,
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Src: image.White,
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Face: face,
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}
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//Put glyphs on atlas
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atlasSizeXF32 := float32(atlasSizeX)
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atlasSizeYF32 := float32(atlasSizeY)
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charsOnLine := 0
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lineDx := fixed.P(0, lineHeight)
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drawer.Dot = fixed.P(0, lineHeight)
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for _, g := range glyphs {
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gBounds, gAdvanceFixed, _ := face.GlyphBounds(g)
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descent := gBounds.Max.Y
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advanceRoundedF32 := float32(gAdvanceFixed.Floor())
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ascent := -gBounds.Min.Y
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heightRounded := (ascent + descent).Floor()
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atlas.Glyphs[g] = FontAtlasGlyph{
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U: float32(drawer.Dot.X.Floor()) / atlasSizeXF32,
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V: (atlasSizeYF32 - float32((drawer.Dot.Y + descent).Floor())) / atlasSizeYF32,
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SizeU: advanceRoundedF32 / atlasSizeXF32,
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SizeV: float32(heightRounded) / atlasSizeYF32,
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Ascent: float32(ascent.Floor()),
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Descent: float32(descent.Floor()),
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Advance: float32(advanceRoundedF32),
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}
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drawer.DrawString(string(g))
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charsOnLine++
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if charsOnLine == charsPerLine {
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charsOnLine = 0
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drawer.Dot.X = 0
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drawer.Dot = drawer.Dot.Add(lineDx)
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}
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}
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return atlas
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}
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func SaveImgToPNG(img image.Image, file string) error {
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outFile, err := os.Create(file)
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if err != nil {
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return err
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}
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defer outFile.Close()
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err = png.Encode(outFile, img)
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if err != nil {
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return err
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}
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return nil
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}
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297
glyphs/glyphs.go
Executable file
297
glyphs/glyphs.go
Executable file
@ -0,0 +1,297 @@
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package glyphs
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import (
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"math/rand"
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"os"
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"unicode"
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"github.com/bloeys/gglm/gglm"
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"github.com/bloeys/nmage/assets"
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"github.com/bloeys/nmage/buffers"
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"github.com/bloeys/nmage/materials"
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"github.com/bloeys/nmage/meshes"
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"github.com/go-gl/gl/v4.1-core/gl"
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"github.com/golang/freetype/truetype"
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)
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type GlyphRend struct {
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Atlas *FontAtlas
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AtlasTex *assets.Texture
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GlyphMesh *meshes.Mesh
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InstancedBuf buffers.Buffer
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GlyphMat *materials.Material
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GlyphCount int32
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GlyphVBO []float32
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}
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//getGlyphRanges returns a list of ranges, each range is: [i][0]<=range<[i][1]
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func getGlyphRanges(f *truetype.Font) (ret [][2]rune) {
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rr := [2]rune{-1, -1}
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for r := rune(0); r <= unicode.MaxRune; r++ {
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if privateUseArea(r) {
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continue
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}
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if f.Index(r) == 0 {
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continue
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}
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if rr[1] == r {
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rr[1] = r + 1
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continue
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}
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if rr[0] != -1 {
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ret = append(ret, rr)
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}
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rr = [2]rune{r, r + 1}
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}
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if rr[0] != -1 {
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ret = append(ret, rr)
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}
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return ret
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}
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func privateUseArea(r rune) bool {
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return 0xe000 <= r && r <= 0xf8ff ||
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0xf0000 <= r && r <= 0xffffd ||
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0x100000 <= r && r <= 0x10fffd
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}
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//getGlyphsFromRanges takes ranges of runes and produces an array of all the runes in these ranges
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func getGlyphsFromRanges(ranges [][2]rune) []rune {
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out := make([]rune, 0)
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for _, rr := range ranges {
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temp := make([]rune, 0, rr[1]-rr[0])
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for r := rr[0]; r < rr[1]; r++ {
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temp = append(temp, r)
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}
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out = append(out, temp...)
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}
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return out
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}
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func (gr *GlyphRend) DrawTextOpenGL(text string, startPos *gglm.Vec3, winWidth, winHeight int32) {
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//The projection matrix fits the screen size. This is needed so we can size and position characters correctly.
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projMtx := gglm.Ortho(0, float32(winWidth), float32(winHeight), 0, 0.1, 10)
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viewMtx := gglm.LookAt(gglm.NewVec3(0, 0, -1), gglm.NewVec3(0, 0, 0), gglm.NewVec3(0, 1, 0))
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projViewMtx := projMtx.Clone().Mul(viewMtx)
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gr.GlyphMat.DiffuseTex = gr.AtlasTex.TexID
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gr.GlyphMat.SetUnifMat4("projViewMat", &projViewMtx.Mat4)
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gr.GlyphMat.Bind()
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//Prepass to pre-allocate the buffer
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rs := []rune(text)
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const floatsPerGlyph = 18
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rCol := rand.Float32()
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gCol := rand.Float32()
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bCol := rand.Float32()
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pos := startPos.Clone()
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instancedData := make([]float32, 0, len(rs)*floatsPerGlyph) //This a larger approximation than needed because we don't count spaces etc
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for i := 0; i < len(rs); i++ {
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r := rs[i]
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g := gr.Atlas.Glyphs[r]
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if r == '\n' {
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startPos.SetY(startPos.Y() - float32(gr.Atlas.LineHeight))
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pos = startPos.Clone()
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continue
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}
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gr.GlyphCount++
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height := float32(g.Ascent + g.Descent)
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scale := gglm.NewVec3(g.Advance, height, 1)
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//See: https://developer.apple.com/library/archive/documentation/TextFonts/Conceptual/CocoaTextArchitecture/Art/glyph_metrics_2x.png
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//Quads are drawn from the center and so that's our baseline. But chars shouldn't be centered, they should follow ascent/decent/advance.
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//To make them do that vertically, we raise them above the baseline (y+height/2), then since they are sitting on top of the baseline we can simply
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//move them down by the decent amount to put them in the correct vertical position.
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//
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//Horizontally the character should be drawn from the left edge not the center, so we just move it forward by advance/2
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drawPos := *pos
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drawPos.SetX(drawPos.X() + g.Advance*0.5)
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drawPos.SetY(drawPos.Y() + height*0.5 - g.Descent)
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instancedData = append(instancedData, []float32{
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g.U, g.V,
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g.U + g.SizeU, g.V,
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g.U, g.V + g.SizeV,
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g.U + g.SizeU, g.V + g.SizeV,
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rCol, gCol, bCol, 1, //Color
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drawPos.X(), drawPos.Y(), drawPos.Z(), //Model pos
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scale.X(), scale.Y(), scale.Z(), //Model scale
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}...)
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pos.SetX(pos.X() + g.Advance)
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}
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gr.GlyphVBO = append(gr.GlyphVBO, instancedData...)
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}
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func (gr *GlyphRend) Draw() {
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gr.InstancedBuf.SetData(gr.GlyphVBO)
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gr.InstancedBuf.Bind()
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gr.GlyphMat.Bind()
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gl.DrawElementsInstanced(gl.TRIANGLES, gr.GlyphMesh.Buf.IndexBufCount, gl.UNSIGNED_INT, gl.PtrOffset(0), gr.GlyphCount)
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gr.InstancedBuf.UnBind()
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gr.GlyphCount = 0
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gr.GlyphVBO = []float32{}
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}
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func (gr *GlyphRend) SetFace(fontOptions *truetype.Options) {
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face := truetype.NewFace(gr.Atlas.Font, fontOptions)
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gr.Atlas = NewFontAtlasFromFont(gr.Atlas.Font, face, uint(fontOptions.Size))
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}
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func (gr *GlyphRend) SetFontFromFile(fontFile string, fontOptions *truetype.Options) error {
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atlas, err := NewFontAtlasFromFile(fontFile, fontOptions)
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if err != nil {
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return err
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}
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gr.Atlas = atlas
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return nil
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}
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func NewGlyphRend(fontFile string, fontOptions *truetype.Options) (*GlyphRend, error) {
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atlas, err := NewFontAtlasFromFile(fontFile, fontOptions)
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if err != nil {
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return nil, err
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}
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//Create OpenGL texture
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pngFileName := fontFile + "atlas.png"
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err = SaveImgToPNG(atlas.Img, pngFileName)
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if err != nil {
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return nil, err
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}
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atlasTex, err := assets.LoadPNGTexture(pngFileName)
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if err != nil {
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return nil, err
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}
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os.Remove(pngFileName)
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gl.BindTexture(gl.TEXTURE_2D, atlasTex.TexID)
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gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
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gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)
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gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
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gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
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gl.BindTexture(gl.TEXTURE_2D, 0)
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//Create glyph mesh
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glyphMesh := &meshes.Mesh{
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Name: "glypQuad",
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//VertPos, UV, Color; Instanced attributes are stored separately
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Buf: buffers.NewBuffer(
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buffers.Element{ElementType: buffers.DataTypeVec3},
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),
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}
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glyphMesh.Buf.SetData([]float32{
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-0.5, -0.5, 0,
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0.5, -0.5, 0,
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-0.5, 0.5, 0,
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0.5, 0.5, 0,
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})
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glyphMesh.Buf.SetIndexBufData([]uint32{
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0, 1, 2,
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1, 3, 2,
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})
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//Setup material
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glyphMat := materials.NewMaterial("glyphMat", "./res/shaders/glyph")
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glyphMat.SetAttribute(glyphMesh.Buf)
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//Create instanced buf and set its instanced attributes.
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//Multiple VBOs under one VAO, one VBO for vertex data, and one VBO for instanced data.
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instancedBuf := buffers.Buffer{
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VAOID: glyphMesh.Buf.VAOID,
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}
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instancedBuf.SetLayout(
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buffers.Element{ElementType: buffers.DataTypeVec2}, //UVST0
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buffers.Element{ElementType: buffers.DataTypeVec2}, //UVST1
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buffers.Element{ElementType: buffers.DataTypeVec2}, //UVST2
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buffers.Element{ElementType: buffers.DataTypeVec2}, //UVST3
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buffers.Element{ElementType: buffers.DataTypeVec4}, //Color
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buffers.Element{ElementType: buffers.DataTypeVec3}, //ModelPos
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buffers.Element{ElementType: buffers.DataTypeVec3}, //ModelScale
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)
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gl.GenBuffers(1, &instancedBuf.BufID)
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if instancedBuf.BufID == 0 {
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panic("Failed to create openGL buffer")
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}
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instancedBuf.Bind()
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gl.BindBuffer(gl.ARRAY_BUFFER, instancedBuf.BufID)
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layout := instancedBuf.GetLayout()
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//4 UV values
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uvEle := layout[0]
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gl.EnableVertexAttribArray(1)
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gl.VertexAttribPointer(1, uvEle.ElementType.CompCount(), uvEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(uvEle.Offset))
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gl.VertexAttribDivisor(1, 1)
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uvEle = layout[1]
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gl.EnableVertexAttribArray(2)
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gl.VertexAttribPointer(2, uvEle.ElementType.CompCount(), uvEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(uvEle.Offset))
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gl.VertexAttribDivisor(2, 1)
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uvEle = layout[2]
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gl.EnableVertexAttribArray(3)
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gl.VertexAttribPointer(3, uvEle.ElementType.CompCount(), uvEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(uvEle.Offset))
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gl.VertexAttribDivisor(3, 1)
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uvEle = layout[3]
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gl.EnableVertexAttribArray(4)
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gl.VertexAttribPointer(4, uvEle.ElementType.CompCount(), uvEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(uvEle.Offset))
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gl.VertexAttribDivisor(4, 1)
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//Rest of instanced attributes
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colorEle := layout[4]
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gl.EnableVertexAttribArray(5)
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gl.VertexAttribPointer(5, colorEle.ElementType.CompCount(), colorEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(colorEle.Offset))
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gl.VertexAttribDivisor(5, 1)
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posEle := layout[5]
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gl.EnableVertexAttribArray(6)
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gl.VertexAttribPointer(6, posEle.ElementType.CompCount(), posEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(posEle.Offset))
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gl.VertexAttribDivisor(6, 1)
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scaleEle := layout[6]
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gl.EnableVertexAttribArray(7)
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gl.VertexAttribPointer(7, scaleEle.ElementType.CompCount(), scaleEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(scaleEle.Offset))
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gl.VertexAttribDivisor(7, 1)
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gl.BindBuffer(gl.ARRAY_BUFFER, 0)
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instancedBuf.UnBind()
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return &GlyphRend{
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Atlas: atlas,
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AtlasTex: &atlasTex,
|
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|
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GlyphMesh: glyphMesh,
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InstancedBuf: instancedBuf,
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GlyphMat: glyphMat,
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GlyphCount: 0,
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GlyphVBO: make([]float32, 0),
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}, nil
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}
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507
main.go
507
main.go
@ -2,31 +2,17 @@ package main
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"image"
|
||||
"image/draw"
|
||||
"image/png"
|
||||
"math"
|
||||
"math/rand"
|
||||
"os"
|
||||
"sync"
|
||||
"time"
|
||||
"unicode"
|
||||
|
||||
"github.com/bloeys/gglm/gglm"
|
||||
"github.com/bloeys/nmage/assets"
|
||||
"github.com/bloeys/nmage/buffers"
|
||||
"github.com/bloeys/nmage/engine"
|
||||
"github.com/bloeys/nmage/input"
|
||||
"github.com/bloeys/nmage/materials"
|
||||
"github.com/bloeys/nmage/meshes"
|
||||
"github.com/bloeys/nmage/renderer/rend3dgl"
|
||||
nmageimgui "github.com/bloeys/nmage/ui/imgui"
|
||||
"github.com/bloeys/nterm/assert"
|
||||
"github.com/go-gl/gl/v4.1-core/gl"
|
||||
"github.com/bloeys/nterm/glyphs"
|
||||
"github.com/golang/freetype/truetype"
|
||||
"github.com/veandco/go-sdl2/sdl"
|
||||
"golang.org/x/image/font"
|
||||
"golang.org/x/image/math/fixed"
|
||||
)
|
||||
|
||||
var _ engine.Game = &program{}
|
||||
@ -42,6 +28,8 @@ type program struct {
|
||||
// * Assert that engine is inited
|
||||
// * Create VAO struct independent from VBO to support multi-VBO use cases (e.g. instancing)
|
||||
// * Move SetAttribute away from material struct
|
||||
// * Fix FPS counter
|
||||
// * Allow texture loading without cache
|
||||
|
||||
func main() {
|
||||
|
||||
@ -68,158 +56,16 @@ func main() {
|
||||
engine.Run(p)
|
||||
}
|
||||
|
||||
type FontTexAtlas struct {
|
||||
Img *image.RGBA
|
||||
Glyphs map[rune]FontTexAtlasGlyph
|
||||
LineHeight int
|
||||
}
|
||||
|
||||
type FontTexAtlasGlyph struct {
|
||||
U float32
|
||||
V float32
|
||||
SizeU float32
|
||||
SizeV float32
|
||||
|
||||
Ascent float32
|
||||
Descent float32
|
||||
Advance float32
|
||||
}
|
||||
|
||||
var fontPointSize uint = 32
|
||||
var atlas *FontTexAtlas
|
||||
var atlasTex assets.Texture
|
||||
var glyphRend *GlyphRend
|
||||
var glyphRend *glyphs.GlyphRend
|
||||
|
||||
func (p *program) Init() {
|
||||
|
||||
var err error
|
||||
atlas, err = createAtlasFromFontFile("./res/fonts/Consolas.ttf", &truetype.Options{Size: float64(fontPointSize), DPI: 72})
|
||||
glyphRend, err = glyphs.NewGlyphRend("./res/fonts/Consolas.ttf", &truetype.Options{Size: float64(fontPointSize), DPI: 72})
|
||||
if err != nil {
|
||||
panic("Failed to create atlas from font file. Err: " + err.Error())
|
||||
}
|
||||
|
||||
glyphRend = NewGlyphRend()
|
||||
}
|
||||
|
||||
func createAtlasFromFontFile(fontFile string, faceOptions *truetype.Options) (*FontTexAtlas, error) {
|
||||
|
||||
fBytes, err := os.ReadFile(fontFile)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
f, err := truetype.Parse(fBytes)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
face := truetype.NewFace(f, faceOptions)
|
||||
atlas := genTextureAtlasFromFace(f, face, uint(faceOptions.Size))
|
||||
|
||||
return atlas, nil
|
||||
}
|
||||
|
||||
func genTextureAtlasFromFace(f *truetype.Font, face font.Face, pointSize uint) *FontTexAtlas {
|
||||
|
||||
const maxAtlasSize = 8192
|
||||
|
||||
glyphs := getGlyphsFromRanges(getGlyphRanges(f))
|
||||
|
||||
assert.T(len(glyphs) > 0, "no glyphs")
|
||||
|
||||
//Choose atlas size
|
||||
atlasSizeX := 512
|
||||
atlasSizeY := 512
|
||||
|
||||
_, charWidthFixed, _ := face.GlyphBounds(glyphs[0])
|
||||
charWidth := charWidthFixed.Floor()
|
||||
lineHeight := face.Metrics().Height.Floor()
|
||||
|
||||
maxLinesInAtlas := atlasSizeY/lineHeight - 1
|
||||
charsPerLine := atlasSizeX / charWidth
|
||||
linesNeeded := int(math.Ceil(float64(len(glyphs)) / float64(charsPerLine)))
|
||||
|
||||
for linesNeeded > maxLinesInAtlas {
|
||||
|
||||
atlasSizeX *= 2
|
||||
atlasSizeY *= 2
|
||||
|
||||
maxLinesInAtlas = atlasSizeY/lineHeight - 1
|
||||
|
||||
charsPerLine = atlasSizeX / charWidth
|
||||
linesNeeded = int(math.Ceil(float64(len(glyphs)) / float64(charsPerLine)))
|
||||
}
|
||||
assert.T(atlasSizeX <= maxAtlasSize, "Atlas size went beyond maximum")
|
||||
|
||||
//Create atlas
|
||||
atlas := &FontTexAtlas{
|
||||
Img: image.NewRGBA(image.Rect(0, 0, atlasSizeX, atlasSizeY)),
|
||||
Glyphs: make(map[rune]FontTexAtlasGlyph, len(glyphs)),
|
||||
LineHeight: lineHeight,
|
||||
}
|
||||
|
||||
//Clear background to black
|
||||
draw.Draw(atlas.Img, atlas.Img.Bounds(), image.Black, image.Point{}, draw.Src)
|
||||
|
||||
drawer := &font.Drawer{
|
||||
Dst: atlas.Img,
|
||||
Src: image.White,
|
||||
Face: face,
|
||||
}
|
||||
|
||||
//Put glyphs on atlas
|
||||
charsOnLine := 0
|
||||
lineDx := fixed.P(0, lineHeight)
|
||||
drawer.Dot = fixed.P(0, lineHeight)
|
||||
for _, g := range glyphs {
|
||||
|
||||
gBounds, gAdvanceFixed, _ := face.GlyphBounds(g)
|
||||
|
||||
descent := gBounds.Max.Y
|
||||
advanceRounded := gAdvanceFixed.Floor()
|
||||
ascent := -gBounds.Min.Y
|
||||
|
||||
heightRounded := (ascent + descent).Floor()
|
||||
|
||||
atlas.Glyphs[g] = FontTexAtlasGlyph{
|
||||
U: float32(drawer.Dot.X.Floor()) / float32(atlasSizeX),
|
||||
V: (float32(atlasSizeY-(drawer.Dot.Y+descent).Floor()) / float32(atlasSizeY)),
|
||||
|
||||
SizeU: float32(advanceRounded) / float32(atlasSizeX),
|
||||
SizeV: (float32(heightRounded) / float32(atlasSizeY)),
|
||||
|
||||
Ascent: float32(ascent.Floor()),
|
||||
Descent: float32(descent.Floor()),
|
||||
Advance: float32(advanceRounded),
|
||||
}
|
||||
drawer.DrawString(string(g))
|
||||
|
||||
charsOnLine++
|
||||
if charsOnLine == charsPerLine {
|
||||
|
||||
charsOnLine = 0
|
||||
drawer.Dot.X = 0
|
||||
drawer.Dot = drawer.Dot.Add(lineDx)
|
||||
}
|
||||
}
|
||||
|
||||
// fmt.Println(atlas.Glyphs)
|
||||
saveImgToDisk(atlas.Img, "atlas.png")
|
||||
return atlas
|
||||
}
|
||||
|
||||
func saveImgToDisk(img image.Image, file string) {
|
||||
|
||||
outFile, err := os.Create(file)
|
||||
if err != nil {
|
||||
panic(err)
|
||||
}
|
||||
defer outFile.Close()
|
||||
|
||||
err = png.Encode(outFile, img)
|
||||
if err != nil {
|
||||
panic(err)
|
||||
}
|
||||
}
|
||||
|
||||
func (p *program) Start() {
|
||||
@ -239,39 +85,17 @@ func (p *program) Update() {
|
||||
p.shouldRun = false
|
||||
}
|
||||
|
||||
fontSizeChanged := false
|
||||
if input.KeyClicked(sdl.K_KP_PLUS) {
|
||||
|
||||
fontPointSize += 2
|
||||
|
||||
var err error
|
||||
atlas, err = createAtlasFromFontFile("./res/fonts/Consolas.ttf", &truetype.Options{Size: float64(fontPointSize), DPI: 72})
|
||||
if err != nil {
|
||||
panic("Failed to create atlas from font file. Err: " + err.Error())
|
||||
}
|
||||
|
||||
//Delete old opengl texture
|
||||
gl.DeleteTextures(1, &atlasTex.TexID)
|
||||
delete(assets.TexturePaths, "./res/fonts/Consolas.ttf")
|
||||
delete(assets.Textures, atlasTex.TexID)
|
||||
|
||||
atlasTex.TexID = 0
|
||||
}
|
||||
|
||||
if input.KeyClicked(sdl.K_KP_MINUS) {
|
||||
|
||||
fontSizeChanged = true
|
||||
} else if input.KeyClicked(sdl.K_KP_MINUS) {
|
||||
fontPointSize -= 2
|
||||
|
||||
var err error
|
||||
atlas, err = createAtlasFromFontFile("./res/fonts/Consolas.ttf", &truetype.Options{Size: float64(fontPointSize), DPI: 72})
|
||||
if err != nil {
|
||||
panic("Failed to create atlas from font file. Err: " + err.Error())
|
||||
fontSizeChanged = true
|
||||
}
|
||||
|
||||
//Delete old opengl texture
|
||||
gl.DeleteTextures(1, &atlasTex.TexID)
|
||||
delete(assets.TexturePaths, "./res/fonts/Consolas.ttf")
|
||||
delete(assets.Textures, atlasTex.TexID)
|
||||
atlasTex.TexID = 0
|
||||
if fontSizeChanged {
|
||||
glyphRend.SetFace(&truetype.Options{Size: float64(fontPointSize), DPI: 72})
|
||||
}
|
||||
}
|
||||
|
||||
@ -286,22 +110,22 @@ func (p *program) Render() {
|
||||
if frameTime.Milliseconds() > 0 {
|
||||
fps = 1 / float32(frameTime.Milliseconds()) * 1000
|
||||
}
|
||||
startFromTop := float32(h) - float32(atlas.LineHeight)
|
||||
glyphRend.drawTextOpenGL(atlas, fmt.Sprintf("FPS=%f", fps), gglm.NewVec3(float32(w)*0.7, startFromTop, 0), w, h)
|
||||
startFromTop := float32(h) - float32(glyphRend.Atlas.LineHeight)
|
||||
glyphRend.DrawTextOpenGL(fmt.Sprintf("FPS=%f", fps), gglm.NewVec3(float32(w)*0.7, startFromTop, 0), w, h)
|
||||
|
||||
//Draw point and texture sizes
|
||||
startFromTop -= float32(atlas.LineHeight)
|
||||
glyphRend.drawTextOpenGL(atlas, fmt.Sprintf("Point size=%d", fontPointSize), gglm.NewVec3(float32(w)*0.7, startFromTop, 0), w, h)
|
||||
startFromTop -= float32(glyphRend.Atlas.LineHeight)
|
||||
glyphRend.DrawTextOpenGL(fmt.Sprintf("Point size=%d", fontPointSize), gglm.NewVec3(float32(w)*0.7, startFromTop, 0), w, h)
|
||||
|
||||
startFromTop -= float32(atlas.LineHeight)
|
||||
glyphRend.drawTextOpenGL(atlas, fmt.Sprintf("Texture size=%d*%d", atlasTex.Width, atlasTex.Height), gglm.NewVec3(float32(w)*0.7, startFromTop, 0), w, h)
|
||||
startFromTop -= float32(glyphRend.Atlas.LineHeight)
|
||||
glyphRend.DrawTextOpenGL(fmt.Sprintf("Texture size=%d*%d", glyphRend.Atlas.Img.Rect.Max.X, glyphRend.Atlas.Img.Rect.Max.Y), gglm.NewVec3(float32(w)*0.7, startFromTop, 0), w, h)
|
||||
|
||||
//Draw all other
|
||||
count := 1000
|
||||
startFromBot := float32(atlas.LineHeight)
|
||||
startFromBot := float32(glyphRend.Atlas.LineHeight)
|
||||
for i := 0; i < count; i++ {
|
||||
glyphRend.drawTextOpenGL(atlas, "Hello friend, how are you?\n", gglm.NewVec3(0, startFromBot, 0), w, h)
|
||||
startFromBot += float32(atlas.LineHeight) * 2
|
||||
glyphRend.DrawTextOpenGL("Hello friend, how are you?\n", gglm.NewVec3(0, startFromBot, 0), w, h)
|
||||
startFromBot += float32(glyphRend.Atlas.LineHeight) * 2
|
||||
}
|
||||
|
||||
gg.Do(func() {
|
||||
@ -330,294 +154,3 @@ func (p *program) ShouldRun() bool {
|
||||
func (p *program) Deinit() {
|
||||
|
||||
}
|
||||
|
||||
//getGlyphRanges returns a list of ranges, each range is: [i][0]<=range<[i][1]
|
||||
func getGlyphRanges(f *truetype.Font) (ret [][2]rune) {
|
||||
rr := [2]rune{-1, -1}
|
||||
for r := rune(0); r <= unicode.MaxRune; r++ {
|
||||
if privateUseArea(r) {
|
||||
continue
|
||||
}
|
||||
if f.Index(r) == 0 {
|
||||
continue
|
||||
}
|
||||
if rr[1] == r {
|
||||
rr[1] = r + 1
|
||||
continue
|
||||
}
|
||||
if rr[0] != -1 {
|
||||
ret = append(ret, rr)
|
||||
}
|
||||
rr = [2]rune{r, r + 1}
|
||||
}
|
||||
if rr[0] != -1 {
|
||||
ret = append(ret, rr)
|
||||
}
|
||||
return ret
|
||||
}
|
||||
|
||||
func privateUseArea(r rune) bool {
|
||||
return 0xe000 <= r && r <= 0xf8ff ||
|
||||
0xf0000 <= r && r <= 0xffffd ||
|
||||
0x100000 <= r && r <= 0x10fffd
|
||||
}
|
||||
|
||||
//getGlyphsFromRanges takes ranges of runes and produces an array of all the runes in these ranges
|
||||
func getGlyphsFromRanges(ranges [][2]rune) []rune {
|
||||
|
||||
out := make([]rune, 0)
|
||||
for _, rr := range ranges {
|
||||
|
||||
temp := make([]rune, 0, rr[1]-rr[0])
|
||||
for r := rr[0]; r < rr[1]; r++ {
|
||||
temp = append(temp, r)
|
||||
}
|
||||
|
||||
out = append(out, temp...)
|
||||
}
|
||||
|
||||
return out
|
||||
}
|
||||
|
||||
var glyphMat *materials.Material
|
||||
|
||||
func (gr *GlyphRend) drawTextOpenGL(atlas *FontTexAtlas, text string, startPos *gglm.Vec3, winWidth, winHeight int32) {
|
||||
|
||||
// if glyphMesh == nil {
|
||||
// glyphMesh = &meshes.Mesh{
|
||||
// Name: "glypQuad",
|
||||
|
||||
// //VertPos, UV, Color
|
||||
// Buf: buffers.NewBuffer(
|
||||
// buffers.Element{ElementType: buffers.DataTypeVec3},
|
||||
// buffers.Element{ElementType: buffers.DataTypeVec2},
|
||||
// buffers.Element{ElementType: buffers.DataTypeVec4},
|
||||
// ),
|
||||
// }
|
||||
|
||||
// glyphMesh.Buf.SetData([]float32{
|
||||
// -0.5, -0.5, 0,
|
||||
// 0, 0,
|
||||
// 1, 1, 1, 1,
|
||||
|
||||
// 0.5, -0.5, 0,
|
||||
// 1, 0,
|
||||
// 1, 1, 1, 1,
|
||||
|
||||
// -0.5, 0.5, 0,
|
||||
// 0, 1,
|
||||
// 1, 1, 1, 1,
|
||||
|
||||
// 0.5, 0.5, 0,
|
||||
// 1, 1,
|
||||
// 1, 1, 1, 1,
|
||||
// })
|
||||
|
||||
// glyphMesh.Buf.SetIndexBufData([]uint32{
|
||||
// 0, 1, 2,
|
||||
// 1, 3, 2,
|
||||
// })
|
||||
// }
|
||||
|
||||
if glyphMat == nil {
|
||||
glyphMat = materials.NewMaterial("glyphMat", "./res/shaders/glyph")
|
||||
}
|
||||
|
||||
if atlasTex.TexID == 0 {
|
||||
|
||||
var err error
|
||||
atlasTex, err = assets.LoadPNGTexture("./atlas.png")
|
||||
if err != nil {
|
||||
panic(err.Error())
|
||||
}
|
||||
|
||||
gl.BindTexture(gl.TEXTURE_2D, atlasTex.TexID)
|
||||
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
|
||||
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)
|
||||
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
|
||||
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
|
||||
gl.BindTexture(gl.TEXTURE_2D, 0)
|
||||
}
|
||||
|
||||
//Prepare to draw
|
||||
// glyphMesh.Buf.Bind()
|
||||
|
||||
//The projection matrix fits the screen size. This is needed so we can size and position characters correctly.
|
||||
projMtx := gglm.Ortho(0, float32(winWidth), float32(winHeight), 0, 0.1, 10)
|
||||
viewMtx := gglm.LookAt(gglm.NewVec3(0, 0, -1), gglm.NewVec3(0, 0, 0), gglm.NewVec3(0, 1, 0))
|
||||
projViewMtx := projMtx.Clone().Mul(viewMtx)
|
||||
|
||||
glyphMat.DiffuseTex = atlasTex.TexID
|
||||
glyphMat.SetUnifMat4("projViewMat", &projViewMtx.Mat4)
|
||||
glyphMat.Bind()
|
||||
|
||||
//Prepass to pre-allocate the buffer
|
||||
rs := []rune(text)
|
||||
const floatsPerGlyph = 18
|
||||
|
||||
rCol := rand.Float32()
|
||||
gCol := rand.Float32()
|
||||
bCol := rand.Float32()
|
||||
|
||||
pos := startPos.Clone()
|
||||
instancedData := make([]float32, 0, len(rs)*floatsPerGlyph) //This a larger approximation than needed because we don't count spaces etc
|
||||
for i := 0; i < len(rs); i++ {
|
||||
|
||||
r := rs[i]
|
||||
g := atlas.Glyphs[r]
|
||||
if r == '\n' {
|
||||
startPos.SetY(startPos.Y() - float32(atlas.LineHeight))
|
||||
pos = startPos.Clone()
|
||||
continue
|
||||
}
|
||||
gr.GlyphCount++
|
||||
|
||||
height := float32(g.Ascent + g.Descent)
|
||||
scale := gglm.NewVec3(g.Advance, height, 1)
|
||||
|
||||
//See: https://developer.apple.com/library/archive/documentation/TextFonts/Conceptual/CocoaTextArchitecture/Art/glyph_metrics_2x.png
|
||||
//Quads are drawn from the center and so that's our baseline. But chars shouldn't be centered, they should follow ascent/decent/advance.
|
||||
//To make them do that vertically, we raise them above the baseline (y+height/2), then since they are sitting on top of the baseline we can simply
|
||||
//move them down by the decent amount to put them in the correct vertical position.
|
||||
//
|
||||
//Horizontally the character should be drawn from the left edge not the center, so we just move it forward by advance/2
|
||||
drawPos := *pos
|
||||
drawPos.SetX(drawPos.X() + g.Advance*0.5)
|
||||
drawPos.SetY(drawPos.Y() + height*0.5 - g.Descent)
|
||||
|
||||
instancedData = append(instancedData, []float32{
|
||||
g.U, g.V,
|
||||
g.U + g.SizeU, g.V,
|
||||
g.U, g.V + g.SizeV,
|
||||
g.U + g.SizeU, g.V + g.SizeV,
|
||||
|
||||
rCol, gCol, bCol, 1, //Color
|
||||
drawPos.X(), drawPos.Y(), drawPos.Z(), //Model pos
|
||||
scale.X(), scale.Y(), scale.Z(), //Model scale
|
||||
}...)
|
||||
|
||||
pos.SetX(pos.X() + g.Advance)
|
||||
}
|
||||
|
||||
gr.GlyphVBO = append(gr.GlyphVBO, instancedData...)
|
||||
}
|
||||
|
||||
type GlyphRend struct {
|
||||
InstancedBuf buffers.Buffer
|
||||
GlyphMesh *meshes.Mesh
|
||||
GlyphCount int32
|
||||
GlyphVBO []float32
|
||||
}
|
||||
|
||||
func (gr *GlyphRend) Draw() {
|
||||
|
||||
gr.InstancedBuf.SetData(gr.GlyphVBO)
|
||||
|
||||
gr.InstancedBuf.Bind()
|
||||
glyphMat.Bind()
|
||||
// gl.DrawElements(gl.TRIANGLES, mesh.Buf.IndexBufCount, gl.UNSIGNED_INT, gl.PtrOffset(0))
|
||||
gl.DrawElementsInstanced(gl.TRIANGLES, gr.GlyphMesh.Buf.IndexBufCount, gl.UNSIGNED_INT, gl.PtrOffset(0), gr.GlyphCount)
|
||||
gr.InstancedBuf.UnBind()
|
||||
|
||||
gr.GlyphCount = 0
|
||||
gr.GlyphVBO = []float32{}
|
||||
}
|
||||
|
||||
func NewGlyphRend() *GlyphRend {
|
||||
|
||||
//Create glyph mesh
|
||||
glyphMesh := &meshes.Mesh{
|
||||
Name: "glypQuad",
|
||||
|
||||
//VertPos, UV, Color; Instanced attributes are stored separately
|
||||
Buf: buffers.NewBuffer(
|
||||
buffers.Element{ElementType: buffers.DataTypeVec3},
|
||||
),
|
||||
}
|
||||
|
||||
glyphMesh.Buf.SetData([]float32{
|
||||
-0.5, -0.5, 0,
|
||||
0.5, -0.5, 0,
|
||||
-0.5, 0.5, 0,
|
||||
0.5, 0.5, 0,
|
||||
})
|
||||
|
||||
glyphMesh.Buf.SetIndexBufData([]uint32{
|
||||
0, 1, 2,
|
||||
1, 3, 2,
|
||||
})
|
||||
|
||||
(*materials.Material).SetAttribute(nil, glyphMesh.Buf)
|
||||
|
||||
//Create instanced buf and set its instanced attributes.
|
||||
//Multiple VBOs under one VAO, one VBO for vertex data, and one VBO for instanced data.
|
||||
instancedBuf := buffers.Buffer{
|
||||
VAOID: glyphMesh.Buf.VAOID,
|
||||
}
|
||||
instancedBuf.SetLayout(
|
||||
buffers.Element{ElementType: buffers.DataTypeVec2}, //UVST0
|
||||
buffers.Element{ElementType: buffers.DataTypeVec2}, //UVST1
|
||||
buffers.Element{ElementType: buffers.DataTypeVec2}, //UVST2
|
||||
buffers.Element{ElementType: buffers.DataTypeVec2}, //UVST3
|
||||
|
||||
buffers.Element{ElementType: buffers.DataTypeVec4}, //Color
|
||||
buffers.Element{ElementType: buffers.DataTypeVec3}, //ModelPos
|
||||
buffers.Element{ElementType: buffers.DataTypeVec3}, //ModelScale
|
||||
)
|
||||
|
||||
gl.GenBuffers(1, &instancedBuf.BufID)
|
||||
if instancedBuf.BufID == 0 {
|
||||
panic("Failed to create openGL buffer")
|
||||
}
|
||||
|
||||
instancedBuf.Bind()
|
||||
gl.BindBuffer(gl.ARRAY_BUFFER, instancedBuf.BufID)
|
||||
layout := instancedBuf.GetLayout()
|
||||
|
||||
//4 UV values
|
||||
uvEle := layout[0]
|
||||
gl.EnableVertexAttribArray(1)
|
||||
gl.VertexAttribPointer(1, uvEle.ElementType.CompCount(), uvEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(uvEle.Offset))
|
||||
gl.VertexAttribDivisor(1, 1)
|
||||
|
||||
uvEle = layout[1]
|
||||
gl.EnableVertexAttribArray(2)
|
||||
gl.VertexAttribPointer(2, uvEle.ElementType.CompCount(), uvEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(uvEle.Offset))
|
||||
gl.VertexAttribDivisor(2, 1)
|
||||
|
||||
uvEle = layout[2]
|
||||
gl.EnableVertexAttribArray(3)
|
||||
gl.VertexAttribPointer(3, uvEle.ElementType.CompCount(), uvEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(uvEle.Offset))
|
||||
gl.VertexAttribDivisor(3, 1)
|
||||
|
||||
uvEle = layout[3]
|
||||
gl.EnableVertexAttribArray(4)
|
||||
gl.VertexAttribPointer(4, uvEle.ElementType.CompCount(), uvEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(uvEle.Offset))
|
||||
gl.VertexAttribDivisor(4, 1)
|
||||
|
||||
//Rest of instanced attributes
|
||||
colorEle := layout[4]
|
||||
gl.EnableVertexAttribArray(5)
|
||||
gl.VertexAttribPointer(5, colorEle.ElementType.CompCount(), colorEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(colorEle.Offset))
|
||||
gl.VertexAttribDivisor(5, 1)
|
||||
|
||||
posEle := layout[5]
|
||||
gl.EnableVertexAttribArray(6)
|
||||
gl.VertexAttribPointer(6, posEle.ElementType.CompCount(), posEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(posEle.Offset))
|
||||
gl.VertexAttribDivisor(6, 1)
|
||||
|
||||
scaleEle := layout[6]
|
||||
gl.EnableVertexAttribArray(7)
|
||||
gl.VertexAttribPointer(7, scaleEle.ElementType.CompCount(), scaleEle.ElementType.GLType(), false, instancedBuf.Stride, gl.PtrOffset(scaleEle.Offset))
|
||||
gl.VertexAttribDivisor(7, 1)
|
||||
|
||||
gl.BindBuffer(gl.ARRAY_BUFFER, 0)
|
||||
instancedBuf.UnBind()
|
||||
|
||||
return &GlyphRend{
|
||||
GlyphMesh: glyphMesh,
|
||||
InstancedBuf: instancedBuf,
|
||||
GlyphCount: 0,
|
||||
GlyphVBO: make([]float32, 0),
|
||||
}
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user