diff options
Diffstat (limited to 'lib')
-rw-r--r-- | lib/libppmd.c | 172 |
1 files changed, 124 insertions, 48 deletions
diff --git a/lib/libppmd.c b/lib/libppmd.c index c7e7ad57..2a998947 100644 --- a/lib/libppmd.c +++ b/lib/libppmd.c @@ -909,8 +909,6 @@ ppmd_circlep(pixel ** const pixels, prevPointExists = FALSE; while (onFirstPoint || !pointsEqual(p, p0)) { - pm_message("Doing point (%d, %d)", p.x, p.y); - if (prevPointExists && pointsEqual(p, prevPoint)) { /* We're on the same point we were on last time (we moved less than a point's worth). Just keep moving. @@ -931,7 +929,6 @@ ppmd_circlep(pixel ** const pixels, sx += e * sy / DDA_SCALE; sy -= e * sx / DDA_SCALE; p = makePoint(sx / DDA_SCALE, sy / DDA_SCALE); - pm_message("next point is (%d, %d)", p.x, p.y); } } } @@ -1407,9 +1404,22 @@ glyphSkipBefore(const struct ppmd_glyph * const glyphP) { return twosCompByteValue(glyphP->header.skipBefore); } +static int +glyphWidth(const struct ppmd_glyph * const glyphP) { + + return twosCompByteValue(glyphP->header.skipAfter) - + twosCompByteValue(glyphP->header.skipBefore); +} + + static ppmd_point commandPoint(const struct ppmd_glyphCommand * const commandP) { - +/*---------------------------------------------------------------------------- + Return the point which is the argument of glyph drawing command + *commandP. The origin of the coordinate system for this point + is the center of the glyph cell and the scale is the scale of the + font, so (-10, -10) means the upper left corner of the glyph cell. +-----------------------------------------------------------------------------*/ return makePoint(twosCompByteValue(commandP->x), twosCompByteValue(commandP->y)); } @@ -1418,32 +1428,102 @@ commandPoint(const struct ppmd_glyphCommand * const commandP) { #define Descend 9 /* Descender offset */ +static ppmd_point +textPosFromFontPos(ppmd_point const fontPos, + ppmd_point const textBoxOrigin, + ppmd_point const center, + ppmd_point const glyphOrigin, + unsigned int const height, + long const rotcos, + long const rotsin) { +/*---------------------------------------------------------------------------- + 'fontPos' is a position within a glyph as told by the font definition. + It is relative to the center of the glyph, in units of font pixels + (1/21 of a glyph cell). + + We return the position on the canvas of that point. + + That takes into account where in the text box we are, where the text box + is on the canvas, the size of the characters, and the rotation of the + text box. +-----------------------------------------------------------------------------*/ + ppmd_point const ptl = vectorSum(center, fontPos); + /* Position relative to the top left of the standard glyph cell */ + + ppmd_point const pl = vectorSum(glyphOrigin, ptl); + /* Position relative to the top left of the whole text box, + assuming the text box is horizontal and has font scale. + */ + + ppmd_point const ps = makePoint((pl.x * (int)height) / Scalef, + (pl.y * (int)height) / Scalef); + /* Same as above, but with the text box its actual size */ + + ppmd_point const retval = + makePoint(textBoxOrigin.x + + (ps.x * rotcos - (ps.y-(int)height) * rotsin) / 65536, + textBoxOrigin.y + + (ps.x * rotsin + (ps.y-(int)height) * rotcos) / 65536); + + ppmd_validatePoint(retval); + + return retval; +} + + static void drawGlyph(const struct ppmd_glyph * const glyphP, - ppmd_point * const glyphCornerP, + ppmd_point const glyphOrigin, pixel ** const pixels, unsigned int const cols, unsigned int const rows, pixval const maxval, int const height, - ppmd_point const pos, + ppmd_point const textBoxOrigin, long const rotcos, long const rotsin, ppmd_drawprocp drawProc, - const void * const clientdata - ) { + const void * const clientdata, + unsigned int * const cursorAdvanceP + ) { /*---------------------------------------------------------------------------- - *pP is either the top left or bottom left corner of the glyph cell - in the output upon entry, and we update it so as to move to the left - edge of the next glyph cell. + 'glyphOrigin' is the position relative to the upper left corner of the text + box of the upper left corner of this glyph cell. It is in units of font + pixels (so you have to scale it by the font size to actual distance on + the canvas). + + We return as *cursorAdvanceP the amount to the right of this glyph cell + the next glyph cell on the line (if any) should be. + + The actual glyph cell may be a little to the left of the nominal position + because of kerning. The font says how much to shift the cell left. + + 'textBoxOrigin' is the left end of the baseline of the top line in the + text box, in the coordinate system of the canvas. 'rotcos' and 'rotsin' + tell how that text box is rotated with respect to the horizontal on the + canvas. + + 'height' is the height in canvas pixels of a glyph. This is a scale factor + to convert font coordinates to canvas coordinates. -----------------------------------------------------------------------------*/ - ppmd_point const glyphCorner = *glyphCornerP; + ppmd_point const center = makePoint(-glyphSkipBefore(glyphP), Scalef/2); + /* This is what you have to add to the coordinates in a glyph + command, which are relative to the center of the glyph, to get + coordinates relative to the upper left corner of the glyph + */ ppmd_point p; + /* Current drawing position within the glyph. Origin is the top + left of the glyph cell. Units are font pixels. + */ unsigned int commandNum; - p = makePoint(glyphCorner.x - glyphSkipBefore(glyphP), glyphCorner.y); - /* initial value */ + p = textPosFromFontPos(makePoint(0, 0), + textBoxOrigin, + center, + glyphOrigin, + height, + rotcos, rotsin); /* initial value */ for (commandNum = 0; commandNum < glyphP->header.commandCount; @@ -1457,41 +1537,30 @@ drawGlyph(const struct ppmd_glyph * const glyphP, break; case CMD_DRAWLINE: { - ppmd_point const n = vectorSum(p, commandPoint(commandP)); - int const mx1 = (p.x * height) / Scalef; - int const my1 = ((p.y - Descend) * height) / Scalef; - int const mx2 = (n.x * height) / Scalef; - int const my2 = ((n.y - Descend) * height) / Scalef; - - /* Note that all points above are with reference to an arbitrary - model co-ordinate system with fixed size and no rotation. - Following are the points that honor the height and angle - specifications. - */ - ppmd_point const t1 = - makePoint(pos.x + (mx1 * rotcos - my1 * rotsin) / 65536, - pos.y + (mx1 * rotsin + my1 * rotcos) / 65536); - ppmd_point const t2 = - makePoint(pos.x + (mx2 * rotcos - my2 * rotsin) / 65536, - pos.y + (mx2 * rotsin + my2 * rotcos) / 65536); - - ppmd_validatePoint(t1); - ppmd_validatePoint(t2); - - ppmd_linep(pixels, cols, rows, maxval, t1, t2, + ppmd_point const n = textPosFromFontPos(commandPoint(commandP), + textBoxOrigin, + center, + glyphOrigin, + height, + rotcos, rotsin); + + ppmd_linep(pixels, cols, rows, maxval, p, n, drawProc, clientdata); p = n; } break; case CMD_MOVEPEN: - p = vectorSum(p, commandPoint(commandP)); + p = textPosFromFontPos(commandPoint(commandP), + textBoxOrigin, + center, + glyphOrigin, + height, + rotcos, rotsin); break; } } - p.x += glyphP->header.skipAfter; - - *glyphCornerP = makePoint(p.x + glyphP->header.skipAfter, glyphCorner.y); + *cursorAdvanceP = glyphWidth(glyphP); } @@ -1508,12 +1577,17 @@ ppmd_textp(pixel** const pixels, ppmd_drawprocp drawProc, const void * const clientdata) { /*---------------------------------------------------------------------------- - Draw the zero-terminated string s, with its baseline starting at point - 'pos', inclined by angle degrees to the X axis, with letters height pixels - high (descenders will extend below the baseline). We pass the supplied - drawproc and clientdata to ppmd_linep, which performs the actual drawing. + Draw the zero-terminated string 'sArg', with its baseline starting at point + 'pos', inclined by 'angle' degrees to the X axis, with letters 'height' + pixels high (descenders will extend below the baseline). We pass the + supplied drawproc and clientdata to ppmd_linep, which performs the actual + drawing. + + There may be multiple lines of text. The baseline of the topmost line + starts at 'pos'. -----------------------------------------------------------------------------*/ const struct ppmd_font * const fontP = ppmd_get_font(); + long rotsin, rotcos; ppmd_point p; const char * s; @@ -1524,8 +1598,7 @@ ppmd_textp(pixel** const pixels, rotsin = isin(-angle); rotcos = icos(-angle); - s = sArg; - while (*s) { + for (s = &sArg[0]; *s; ) { unsigned char const ch = *s++; if (ch >= fontP->header.firstCodePoint && @@ -1534,11 +1607,14 @@ ppmd_textp(pixel** const pixels, const struct ppmd_glyph * const glyphP = &fontP->glyphTable[ch - fontP->header.firstCodePoint]; + unsigned int cursorAdvance; + ppmd_validatePoint(p); - drawGlyph(glyphP, &p, pixels, cols, rows, maxval, + drawGlyph(glyphP, p, pixels, cols, rows, maxval, height, pos, rotcos, rotsin, - drawProc, clientdata); + drawProc, clientdata, &cursorAdvance); + p.x += cursorAdvance; } else if (ch == '\n') { /* Move to the left edge of the next line down */ p.y += Scalef + Descend; |