void PNGLoader::grayscale_to_4ub(int count)
{
unsigned char *input = scanline;
if (bit_depth == 1)
{
if (!has_colorkey)
{
for (int i = 0; i < count; i++)
{
int shift = i % 8;
unsigned char value = (input[i / 8] >> shift) & 1;
value = static_cast<int>(value)* 255;
scanline_4ub[i] = Vec4ub(value, value, value, 255);
}
}
else
{
for (int i = 0; i < count; i++)
{
int shift = i % 8;
unsigned char value = (input[i / 8] >> shift) & 1;
unsigned char alpha = (value != colorkey.r) ? 255 : 0;
value = static_cast<int>(value)* 255;
scanline_4ub[i] = Vec4ub(value, value, value, alpha);
}
}
}
void PNGLoader::decode_palette()
{
if (color_type == 3) // indexed
{
if (plte.is_null() || plte.get_size() % 3 != 0)
throw Exception("Invalid PNG image file");
int num_entries = plte.get_size() / 3;
if (num_entries > 256)
throw Exception("Invalid PNG image file");
unsigned char *entries = reinterpret_cast<unsigned char*>(plte.get_data());
palette = static_cast<Vec4ub *>(System::aligned_alloc(256 * sizeof(Vec4ub)));
for (int i = 0; i < num_entries; i++)
palette[i] = Vec4ub(entries[i * 3], entries[i * 3 + 1], entries[i * 3 + 2], 255);
if (!trns.is_null())
{
int num_alpha_entries = trns.get_size();
if (num_alpha_entries > num_entries)
throw Exception("Invalid PNG image file");
unsigned char *alpha_entries = reinterpret_cast<unsigned char*>(trns.get_data());
for (int i = 0; i < num_alpha_entries; i++)
palette[i].a = alpha_entries[i];
}
}
}
FontPixelBuffer FontEngine_Win32::get_font_glyph_gray8(int glyph)
{
DataBuffer glyph_bitmap;
GLYPHMETRICS glyph_metrics = { 0 };
MAT2 matrix = { 0 };
matrix.eM11.value = 1;
matrix.eM22.value = 1;
if (try_load_glyph_bitmap(glyph, GGO_GRAY8_BITMAP, matrix, glyph_bitmap, glyph_metrics))
{
PixelBuffer pixelbuffer(glyph_metrics.gmBlackBoxX, glyph_metrics.gmBlackBoxY, tf_rgba8);
DWORD s_pitch = (glyph_metrics.gmBlackBoxX + 3) / 4 * 4;
unsigned char *s = (unsigned char *) glyph_bitmap.get_data();
DWORD d_width = glyph_metrics.gmBlackBoxX;
Vec4ub *d = pixelbuffer.get_data<Vec4ub>();
for (DWORD py = 0; py < glyph_metrics.gmBlackBoxY; py++)
{
for (DWORD px = 0; px < glyph_metrics.gmBlackBoxX; px++)
{
DWORD gray = s[px + py*s_pitch];
d[px + py*d_width] = Vec4ub(255, 255, 255, (gray * 255 + 32) / 64);
}
}
FontPixelBuffer font_buffer;
font_buffer.glyph = glyph;
font_buffer.buffer = pixelbuffer;
font_buffer.buffer_rect = pixelbuffer.get_size();
font_buffer.offset.x = glyph_metrics.gmptGlyphOrigin.x;
font_buffer.offset.y = -glyph_metrics.gmptGlyphOrigin.y;
font_buffer.empty_buffer = false;
font_buffer.metrics.advance.width = glyph_metrics.gmCellIncX;
font_buffer.metrics.advance.height = glyph_metrics.gmCellIncY;
font_buffer.metrics.bbox_offset.x = glyph_metrics.gmptGlyphOrigin.x;
font_buffer.metrics.bbox_offset.y = -glyph_metrics.gmptGlyphOrigin.y;
font_buffer.metrics.bbox_size.width = glyph_metrics.gmBlackBoxX;
font_buffer.metrics.bbox_size.height = glyph_metrics.gmBlackBoxY;
return font_buffer;
}
else
{
return get_empty_font_glyph(glyph);
}
}
