Handle tabs

This commit is contained in:
bloeys
2022-07-04 02:45:59 +04:00
parent c82fd6aac7
commit 0ff7f051f6
2 changed files with 43 additions and 33 deletions

View File

@ -14,7 +14,7 @@ import (
)
const floatsPerGlyph = 11
const maxGlyphsPerBatch = 16384
const MaxGlyphsPerBatch = 16384
type GlyphRend struct {
Atlas *FontAtlas
@ -24,7 +24,7 @@ type GlyphRend struct {
InstancedBuf buffers.Buffer
GlyphMat *materials.Material
GlyphCount int32
GlyphCount uint32
//NOTE: Because of the sad realities (bugs?) of CGO, passing an array in a struct
//to C explodes (Go pointer to Go pointer error) even though passing the same array
//allocated inside the function is fine (Go potentially can't detect what's happening properly).
@ -35,6 +35,8 @@ type GlyphRend struct {
ScreenWidth int32
ScreenHeight int32
SpacesPerTab uint
}
//DrawTextOpenGLAbs prepares text that will be drawn on the next GlyphRend.Draw call.
@ -57,20 +59,25 @@ func (gr *GlyphRend) DrawTextOpenGLAbs(text string, screenPos *gglm.Vec3, color
pos := screenPos.Clone()
advanceF32 := float32(gr.Atlas.Advance)
lineHeightF32 := float32(gr.Atlas.LineHeight)
scale := gglm.NewVec2(advanceF32, lineHeightF32)
buffIndex := gr.GlyphCount * floatsPerGlyph
for i := 0; i < len(rs); i++ {
r := rs[i]
g := gr.Atlas.Glyphs[r]
if r == '\n' {
screenPos.SetY(screenPos.Y() - lineHeightF32)
pos = screenPos.Clone()
continue
} else if r == ' ' {
pos.SetX(pos.X() + advanceF32)
pos.AddX(advanceF32)
continue
} else if r == '\t' {
pos.AddX(advanceF32 * float32(gr.SpacesPerTab))
continue
}
scale := gglm.NewVec2(advanceF32, lineHeightF32)
g := gr.Atlas.Glyphs[r]
//See: https://developer.apple.com/library/archive/documentation/TextFonts/Conceptual/CocoaTextArchitecture/Art/glyph_metrics_2x.png
//The uvs coming in make it so that glyphs are sitting on top of the baseline (no descent) and with horizontal bearing applied.
@ -80,33 +87,34 @@ func (gr *GlyphRend) DrawTextOpenGLAbs(text string, screenPos *gglm.Vec3, color
drawPos.SetY(drawPos.Y() - g.Descent)
//Add the glyph information to the vbo
startIndex := gr.GlyphCount * floatsPerGlyph
//UV
gr.GlyphVBO[startIndex+0] = g.U
gr.GlyphVBO[startIndex+1] = g.V
gr.GlyphVBO[buffIndex+0] = g.U
gr.GlyphVBO[buffIndex+1] = g.V
//Color
gr.GlyphVBO[startIndex+2] = color.R()
gr.GlyphVBO[startIndex+3] = color.G()
gr.GlyphVBO[startIndex+4] = color.B()
gr.GlyphVBO[startIndex+5] = color.A()
gr.GlyphVBO[buffIndex+2] = color.R()
gr.GlyphVBO[buffIndex+3] = color.G()
gr.GlyphVBO[buffIndex+4] = color.B()
gr.GlyphVBO[buffIndex+5] = color.A()
//Model Pos
gr.GlyphVBO[startIndex+6] = roundF32(drawPos.X())
gr.GlyphVBO[startIndex+7] = roundF32(drawPos.Y())
gr.GlyphVBO[startIndex+8] = drawPos.Z()
gr.GlyphVBO[buffIndex+6] = roundF32(drawPos.X())
gr.GlyphVBO[buffIndex+7] = roundF32(drawPos.Y())
gr.GlyphVBO[buffIndex+8] = drawPos.Z()
//Model Scale
gr.GlyphVBO[startIndex+9] = scale.X()
gr.GlyphVBO[startIndex+10] = scale.Y()
gr.GlyphVBO[buffIndex+9] = scale.X()
gr.GlyphVBO[buffIndex+10] = scale.Y()
gr.GlyphCount++
pos.SetX(pos.X() + advanceF32)
pos.AddX(advanceF32)
//If we fill the buffer we issue a draw call
if gr.GlyphCount == maxGlyphsPerBatch {
if gr.GlyphCount == MaxGlyphsPerBatch {
gr.Draw()
buffIndex = 0
} else {
buffIndex += floatsPerGlyph
}
}
}
@ -121,7 +129,7 @@ func (gr *GlyphRend) Draw() {
gr.InstancedBuf.Bind()
gr.GlyphMat.Bind()
gl.DrawElementsInstanced(gl.TRIANGLES, gr.GlyphMesh.Buf.IndexBufCount, gl.UNSIGNED_INT, gl.PtrOffset(0), gr.GlyphCount)
gl.DrawElementsInstanced(gl.TRIANGLES, gr.GlyphMesh.Buf.IndexBufCount, gl.UNSIGNED_INT, gl.PtrOffset(0), int32(gr.GlyphCount))
gr.GlyphCount = 0
}
@ -200,8 +208,9 @@ func (gr *GlyphRend) SetScreenSize(screenWidth, screenHeight int32) {
func NewGlyphRend(fontFile string, fontOptions *truetype.Options, screenWidth, screenHeight int32) (*GlyphRend, error) {
gr := &GlyphRend{
GlyphCount: 0,
GlyphVBO: make([]float32, floatsPerGlyph*maxGlyphsPerBatch),
GlyphCount: 0,
GlyphVBO: make([]float32, floatsPerGlyph*MaxGlyphsPerBatch),
SpacesPerTab: 4,
}
//Create glyph mesh