freetype/truetype: implement SHP and DELTAP opcodes.

R=bsiegert
CC=golang-dev, remyoudompheng
https://codereview.appspot.com/16500043
This commit is contained in:
Nigel Tao 2013-10-25 20:07:33 +11:00
parent 486e1683dd
commit ab80f5823d
3 changed files with 67 additions and 9 deletions

View file

@ -480,6 +480,24 @@ func (h *Hinter) run(program []byte, pCurrent, pUnhinted, pInFontUnits []Point,
prevEnd = end
}
case opSHP0, opSHP1:
if top < int(h.gs.loop) {
return errors.New("truetype: hinting: stack underflow")
}
_, _, d, ok := h.displacement(opcode&1 == 0)
if !ok {
return errors.New("truetype: hinting: point out of range")
}
for ; h.gs.loop != 0; h.gs.loop-- {
top--
p := h.point(2, current, h.stack[top])
if p == nil {
return errors.New("truetype: hinting: point out of range")
}
h.move(p, d, true)
}
h.gs.loop = 1
case opSHZ0, opSHZ1:
top--
zonePointer, i, d, ok := h.displacement(opcode&1 == 0)
@ -740,6 +758,9 @@ func (h *Hinter) run(program []byte, pCurrent, pUnhinted, pInFontUnits []Point,
case opNOT:
h.stack[top-1] = bool2int32(h.stack[top-1] == 0)
case opDELTAP1:
goto deltap
case opSDB:
top--
h.gs.deltaBase = h.stack[top]
@ -794,6 +815,9 @@ func (h *Hinter) run(program []byte, pCurrent, pUnhinted, pInFontUnits []Point,
// This code does not implement engine compensation, as we don't expect to
// be used to output on dot-matrix printers.
case opDELTAP2, opDELTAP3:
goto deltap
case opSROUND, opS45ROUND:
top--
switch (h.stack[top] >> 6) & 0x03 {
@ -1130,6 +1154,40 @@ func (h *Hinter) run(program []byte, pCurrent, pUnhinted, pInFontUnits []Point,
}
continue
}
deltap:
top--
n := f26dot6(h.stack[top])
if top < 2*int(h.gs.loop) {
return errors.New("truetype: hinting: stack underflow")
}
for ; n > 0; n-- {
top -= 2
p := h.point(0, current, h.stack[top+1])
if p == nil {
return errors.New("truetype: hinting: point out of range")
}
b := h.stack[top]
c := (b & 0xf0) >> 4
switch opcode {
case opDELTAP2:
c += 16
case opDELTAP3:
c += 32
}
c += h.gs.deltaBase
if ppem := (h.scale + 1<<5) >> 6; ppem != c {
continue
}
b = (b & 0x0f) - 8
if b >= 0 {
b++
}
b = b * 64 / (1 << uint32(h.gs.deltaShift))
h.move(p, f26dot6(b), true)
}
pc++
continue
}
return nil
}

View file

@ -60,8 +60,8 @@ const (
opMDAP1 = 0x2f // .
opIUP0 = 0x30 // Interpolate Untouched Points through the outline
opIUP1 = 0x31 // .
opSHP0 = 0x32
opSHP1 = 0x33
opSHP0 = 0x32 // SHift Point using reference point
opSHP1 = 0x33 // .
opSHC0 = 0x34
opSHC1 = 0x35
opSHZ0 = 0x36 // SHift Zone using reference point
@ -103,7 +103,7 @@ const (
opAND = 0x5a // logical AND
opOR = 0x5b // logical OR
opNOT = 0x5c // logical NOT
opDELTAP1 = 0x5d
opDELTAP1 = 0x5d // DELTA exception P1
opSDB = 0x5e // Set Delta Base in the graphics state
opSDS = 0x5f // Set Delta Shift in the graphics state
opADD = 0x60 // ADD
@ -123,8 +123,8 @@ const (
opNROUND10 = 0x6e // .
opNROUND11 = 0x6f // .
opWCVTF = 0x70
opDELTAP2 = 0x71
opDELTAP3 = 0x72
opDELTAP2 = 0x71 // DELTA exception P2
opDELTAP3 = 0x72 // DELTA exception P3
opDELTAC1 = 0x73
opDELTAC2 = 0x74
opDELTAC3 = 0x75
@ -274,11 +274,11 @@ var popCount = [256]uint8{
0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 2, 2, 0, 0, 0, q, // 0x00 - 0x0f
1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, // 0x10 - 0x1f
1, 1, 0, 2, 0, 1, 1, q, q, q, 2, 1, 1, 0, 1, 1, // 0x20 - 0x2f
0, 0, q, q, q, q, 1, 1, 1, 0, 2, 2, 0, 0, 2, 2, // 0x30 - 0x3f
0, 0, 0, 0, q, q, 1, 1, 1, 0, 2, 2, 0, 0, 2, 2, // 0x30 - 0x3f
0, 0, 2, 1, 2, 1, 1, 1, q, 2, 2, 0, 0, 0, 0, 0, // 0x40 - 0x4f
2, 2, 2, 2, 2, 2, 1, 1, 1, 0, 2, 2, 1, q, 1, 1, // 0x50 - 0x5f
2, 2, 2, 2, 2, 2, 1, 1, 1, 0, 2, 2, 1, 1, 1, 1, // 0x50 - 0x5f
2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 0x60 - 0x6f
q, q, q, q, q, q, 1, 1, 2, 2, 0, q, 0, 0, 1, 1, // 0x70 - 0x7f
q, 1, 1, q, q, q, 1, 1, 2, 2, 0, q, 0, 0, 1, 1, // 0x70 - 0x7f
q, q, q, q, q, 1, q, q, 1, 1, 3, 2, 2, 1, q, q, // 0x80 - 0x8f
q, q, q, q, q, q, q, q, q, q, q, q, q, q, q, q, // 0x90 - 0x9f
q, q, q, q, q, q, q, q, q, q, q, q, q, q, q, q, // 0xa0 - 0xaf

View file

@ -253,7 +253,7 @@ var scalingTestCases = []struct {
}{
{"luxisr", 12, -1},
{"x-arial-bold", 11, 0},
{"x-deja-vu-sans-oblique", 17, 5},
{"x-deja-vu-sans-oblique", 17, 14},
{"x-droid-sans-japanese", 9, 0},
{"x-times-new-roman", 13, 0},
}