public void DrawString(char[] buffer, int startAt, int len, double left, double top)
{
_vboBuilder.Clear();
_vboBuilder.SetTextureInfo(_glBmp.Width, _glBmp.Height, _glBmp.IsYFlipped, _pcx.OriginKind);
//
_pcx.FontFillColor = _painter.FontFillColor;
_pcx.LoadTexture(_glBmp);
//create temp buffer span that describe the part of a whole char buffer
TextBufferSpan textBufferSpan = new TextBufferSpan(buffer, startAt, len);
//ask text service to parse user input char buffer and create a glyph-plan-sequence (list of glyph-plan)
//with specific request font
GlyphPlanSequence glyphPlanSeq = _textServices.CreateGlyphPlanSeq(ref textBufferSpan, _font);
float px_scale = _px_scale;
//--------------------------
//TODO:
//if (x,y) is left top
//we need to adjust y again
float scaleFromTexture = 1;
TextureKind textureKind = _fontAtlas.TextureKind;
float g_left = 0;
float g_top = 0;
int baseLine = (int)Math.Round((float)top + _font.AscentInPixels);
int bottom = (int)Math.Round((float)top + _font.AscentInPixels - _font.DescentInPixels);
float acc_x = 0; //local accumulate x
float acc_y = 0; //local accumulate y
#if DEBUG
if (s_dbugShowMarkers)
{
if (s_dbugShowGlyphTexture)
{
//show original glyph texture at top
_pcx.DrawImage(_glBmp, 0, 0);
}
//draw red-line-marker for baseLine
_painter.StrokeColor = Color.Red;
_painter.DrawLine(left, baseLine, left + 200, baseLine);
//
//draw magenta-line-marker for bottom line
_painter.StrokeColor = Color.Magenta;
int bottomLine = (int)Math.Round((float)top + _font.LineSpacingInPixels);
_painter.DrawLine(left, bottomLine, left + 200, bottomLine);
//draw blue-line-marker for top line
_painter.StrokeColor = Color.Blue;
_painter.DrawLine(0, top, left + 200, top);
}
DrawingTechnique = s_dbugDrawTechnique; //for debug only
UseVBO = s_dbugUseVBO; //for debug only
#endif
int seqLen = glyphPlanSeq.Count;
for (int i = 0; i < seqLen; ++i)
{
UnscaledGlyphPlan glyph = glyphPlanSeq[i];
Typography.Rendering.TextureGlyphMapData glyphData;
if (!_fontAtlas.TryGetGlyphMapData(glyph.glyphIndex, out glyphData))
{
//if no glyph data, we should render a missing glyph ***
continue;
}
//--------------------------------------
//TODO: review precise height in float
//--------------------------------------
//paint src rect
//temp fix, glyph texture img is not flipped
//but the associate info is flipped => so
//we need remap exact Y from the image
Rectangle srcRect =
new Rectangle(glyphData.Left,
_glBmp.Height - (glyphData.Top + glyphData.Height),
glyphData.Width,
glyphData.Height);
//offset length from 'base-line'
float x_offset = acc_x + (float)Math.Round(glyph.OffsetX * px_scale - glyphData.TextureXOffset);
float y_offset = acc_y + (float)Math.Round(glyph.OffsetY * px_scale - glyphData.TextureYOffset) + srcRect.Height; //***
//NOTE:
// -glyphData.TextureXOffset => restore to original pos
// -glyphData.TextureYOffset => restore to original pos
//--------------------------
g_left = (float)(left + x_offset);
g_top = (float)(bottom - y_offset); //***
acc_x += (float)Math.Round(glyph.AdvanceX * px_scale);
//g_x = (float)Math.Round(g_x); //***
g_top = (float)Math.Floor(g_top);//adjust to integer num ***
#if DEBUG
if (s_dbugShowMarkers)
{
if (s_dbugShowGlyphTexture)
{
//draw yellow-rect-marker on original texture
_painter.DrawRectangle(srcRect.X, srcRect.Y, srcRect.Width, srcRect.Height, Color.Yellow);
}
//draw debug-rect box at target glyph position
_painter.DrawRectangle(g_left, g_top, srcRect.Width, srcRect.Height, Color.Black);
_painter.StrokeColor = Color.Blue; //restore
}
#endif
if (textureKind == TextureKind.Msdf)
{
_pcx.DrawSubImageWithMsdf(_glBmp,
ref srcRect,
g_left,
g_top,
scaleFromTexture);
}
else
{
switch (DrawingTechnique)
{
case GlyphTexturePrinterDrawingTechnique.Stencil:
if (UseVBO)
{
_vboBuilder.WriteVboToList(
ref srcRect,
g_left, g_top);
}
else
{
//stencil gray scale with fill-color
_pcx.DrawGlyphImageWithStecil(_glBmp,
ref srcRect,
g_left,
g_top,
scaleFromTexture);
}
break;
case GlyphTexturePrinterDrawingTechnique.Copy:
if (UseVBO)
{
_vboBuilder.WriteVboToList(
ref srcRect,
g_left, g_top);
}
else
{
_pcx.DrawSubImage(_glBmp,
ref srcRect,
g_left,
g_top,
1);
}
break;
case GlyphTexturePrinterDrawingTechnique.LcdSubPixelRendering:
if (UseVBO)
{
_vboBuilder.WriteVboToList(
ref srcRect,
g_left, g_top);
}
else
{
_pcx.DrawGlyphImageWithSubPixelRenderingTechnique2_GlyphByGlyph(
ref srcRect,
g_left,
g_top,
1);
}
break;
}
}
}
//-------------------------------------------
//
if (UseVBO)
{
switch (DrawingTechnique)
{
case GlyphTexturePrinterDrawingTechnique.Copy:
_pcx.DrawGlyphImageWithCopy_VBO(_vboBuilder);
break;
case GlyphTexturePrinterDrawingTechnique.LcdSubPixelRendering:
_pcx.DrawGlyphImageWithSubPixelRenderingTechnique3_DrawElements(_vboBuilder);
break;
case GlyphTexturePrinterDrawingTechnique.Stencil:
_pcx.DrawGlyphImageWithStecil_VBO(_vboBuilder);
break;
}
_vboBuilder.Clear();
}
}
