mirrors/imgui
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

ImFontAtlas: Re-arranging code to simplify implementation of imgui_freetype. (#618)

Browse Source
This commit is contained in:
omar 2017-08-17 21:19:54 +08:00
parent 1086c87767
commit 8be7a60f20
2 changed files with 40 additions and 33 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

72
imgui_draw.cpp
View File

@ -1336,40 +1336,45 @@ void ImFontAtlas::CustomRectCalcUV(const CustomRect* rect, ImVec2* out_uv_min, I
bool ImFontAtlas::Build()
{
IM_ASSERT(ConfigData.Size > 0);
return ImFontAtlasBuildWithStbTruetype(this);
}
ImFontAtlasBuildRegisterDefaultCustomRects(this);
bool ImFontAtlasBuildWithStbTruetype(ImFontAtlas* atlas)
{
IM_ASSERT(atlas->ConfigData.Size > 0);
TexID = NULL;
TexWidth = TexHeight = 0;
TexUvWhitePixel = ImVec2(0, 0);
ClearTexData();
ImFontAtlasBuildRegisterDefaultCustomRects(atlas);
atlas->TexID = NULL;
atlas->TexWidth = atlas->TexHeight = 0;
atlas->TexUvWhitePixel = ImVec2(0, 0);
atlas->ClearTexData();
// Count glyphs/ranges
int total_glyphs_count = 0;
int total_ranges_count = 0;
for (int input_i = 0; input_i < ConfigData.Size; input_i++)
for (int input_i = 0; input_i < atlas->ConfigData.Size; input_i++)
{
ImFontConfig& cfg = ConfigData[input_i];
ImFontConfig& cfg = atlas->ConfigData[input_i];
if (!cfg.GlyphRanges)
cfg.GlyphRanges = GetGlyphRangesDefault();
cfg.GlyphRanges = atlas->GetGlyphRangesDefault();
for (const ImWchar* in_range = cfg.GlyphRanges; in_range[0] && in_range[1]; in_range += 2, total_ranges_count++)
total_glyphs_count += (in_range[1] - in_range[0]) + 1;
}
// We need a width for the skyline algorithm. Using a dumb heuristic here to decide of width. User can override TexDesiredWidth and TexGlyphPadding if they wish.
// Width doesn't really matter much, but some API/GPU have texture size limitations and increasing width can decrease height.
TexWidth = (TexDesiredWidth > 0) ? TexDesiredWidth : (total_glyphs_count > 4000) ? 4096 : (total_glyphs_count > 2000) ? 2048 : (total_glyphs_count > 1000) ? 1024 : 512;
TexHeight = 0;
atlas->TexWidth = (atlas->TexDesiredWidth > 0) ? atlas->TexDesiredWidth : (total_glyphs_count > 4000) ? 4096 : (total_glyphs_count > 2000) ? 2048 : (total_glyphs_count > 1000) ? 1024 : 512;
atlas->TexHeight = 0;
// Start packing
const int max_tex_height = 1024*32;
stbtt_pack_context spc;
stbtt_PackBegin(&spc, NULL, TexWidth, max_tex_height, 0, TexGlyphPadding, NULL);
stbtt_PackBegin(&spc, NULL, atlas->TexWidth, max_tex_height, 0, atlas->TexGlyphPadding, NULL);
stbtt_PackSetOversampling(&spc, 1, 1);
// Pack our extra data rectangles first, so it will be on the upper-left corner of our texture (UV will have small values).
ImFontAtlasBuildPackCustomRects(this, spc.pack_info);
ImFontAtlasBuildPackCustomRects(atlas, spc.pack_info);
// Initialize font information (so we can error without any cleanup)
struct ImFontTempBuildData
@ -1379,12 +1384,13 @@ bool ImFontAtlas::Build()
stbtt_pack_range* Ranges;
int RangesCount;
};
ImFontTempBuildData* tmp_array = (ImFontTempBuildData*)ImGui::MemAlloc((size_t)ConfigData.Size * sizeof(ImFontTempBuildData));
for (int input_i = 0; input_i < ConfigData.Size; input_i++)
ImFontTempBuildData* tmp_array = (ImFontTempBuildData*)ImGui::MemAlloc((size_t)atlas->ConfigData.Size * sizeof(ImFontTempBuildData));
for (int input_i = 0; input_i < atlas->ConfigData.Size; input_i++)
{
ImFontConfig& cfg = ConfigData[input_i];
ImFontConfig& cfg = atlas->ConfigData[input_i];
ImFontTempBuildData& tmp = tmp_array[input_i];
IM_ASSERT(cfg.DstFont && (!cfg.DstFont->IsLoaded() || cfg.DstFont->ContainerAtlas == this));
IM_ASSERT(cfg.DstFont && (!cfg.DstFont->IsLoaded() || cfg.DstFont->ContainerAtlas == atlas));
const int font_offset = stbtt_GetFontOffsetForIndex((unsigned char*)cfg.FontData, cfg.FontNo);
IM_ASSERT(font_offset >= 0);
if (!stbtt_InitFont(&tmp.FontInfo, (unsigned char*)cfg.FontData, font_offset))
@ -1401,9 +1407,9 @@ bool ImFontAtlas::Build()
memset(buf_ranges, 0, total_ranges_count * sizeof(stbtt_pack_range));
// First font pass: pack all glyphs (no rendering at this point, we are working with rectangles in an infinitely tall texture at this point)
for (int input_i = 0; input_i < ConfigData.Size; input_i++)
for (int input_i = 0; input_i < atlas->ConfigData.Size; input_i++)
{
ImFontConfig& cfg = ConfigData[input_i];
ImFontConfig& cfg = atlas->ConfigData[input_i];
ImFontTempBuildData& tmp = tmp_array[input_i];
// Setup ranges
@ -1436,23 +1442,23 @@ bool ImFontAtlas::Build()
// Extend texture height
for (int i = 0; i < n; i++)
if (tmp.Rects[i].was_packed)
TexHeight = ImMax(TexHeight, tmp.Rects[i].y + tmp.Rects[i].h);
atlas->TexHeight = ImMax(atlas->TexHeight, tmp.Rects[i].y + tmp.Rects[i].h);
}
IM_ASSERT(buf_rects_n == total_glyphs_count);
IM_ASSERT(buf_packedchars_n == total_glyphs_count);
IM_ASSERT(buf_ranges_n == total_ranges_count);
// Create texture
TexHeight = ImUpperPowerOfTwo(TexHeight);
TexPixelsAlpha8 = (unsigned char*)ImGui::MemAlloc(TexWidth * TexHeight);
memset(TexPixelsAlpha8, 0, TexWidth * TexHeight);
spc.pixels = TexPixelsAlpha8;
spc.height = TexHeight;
atlas->TexHeight = ImUpperPowerOfTwo(atlas->TexHeight);
atlas->TexPixelsAlpha8 = (unsigned char*)ImGui::MemAlloc(atlas->TexWidth * atlas->TexHeight);
memset(atlas->TexPixelsAlpha8, 0, atlas->TexWidth * atlas->TexHeight);
spc.pixels = atlas->TexPixelsAlpha8;
spc.height = atlas->TexHeight;
// Second pass: render font characters
for (int input_i = 0; input_i < ConfigData.Size; input_i++)
for (int input_i = 0; input_i < atlas->ConfigData.Size; input_i++)
{
ImFontConfig& cfg = ConfigData[input_i];
ImFontConfig& cfg = atlas->ConfigData[input_i];
ImFontTempBuildData& tmp = tmp_array[input_i];
stbtt_PackSetOversampling(&spc, cfg.OversampleH, cfg.OversampleV);
stbtt_PackFontRangesRenderIntoRects(&spc, &tmp.FontInfo, tmp.Ranges, tmp.RangesCount, tmp.Rects);
@ -1465,9 +1471,9 @@ bool ImFontAtlas::Build()
buf_rects = NULL;
// Third pass: setup ImFont and glyphs for runtime
for (int input_i = 0; input_i < ConfigData.Size; input_i++)
for (int input_i = 0; input_i < atlas->ConfigData.Size; input_i++)
{
ImFontConfig& cfg = ConfigData[input_i];
ImFontConfig& cfg = atlas->ConfigData[input_i];
ImFontTempBuildData& tmp = tmp_array[input_i];
ImFont* dst_font = cfg.DstFont; // We can have multiple input fonts writing into a same destination font (when using MergeMode=true)
@ -1477,7 +1483,7 @@ bool ImFontAtlas::Build()
float ascent = unscaled_ascent * font_scale;
float descent = unscaled_descent * font_scale;
ImFontAtlasBuildSetupFont(this, dst_font, &cfg, ascent, descent);
ImFontAtlasBuildSetupFont(atlas, dst_font, &cfg, ascent, descent);
float off_x = cfg.GlyphOffset.x;
float off_y = cfg.GlyphOffset.y + (float)(int)(dst_font->Ascent + 0.5f);
@ -1497,7 +1503,7 @@ bool ImFontAtlas::Build()
stbtt_aligned_quad q;
float dummy_x = 0.0f, dummy_y = 0.0f;
stbtt_GetPackedQuad(range.chardata_for_range, TexWidth, TexHeight, char_idx, &dummy_x, &dummy_y, &q, 0);
stbtt_GetPackedQuad(range.chardata_for_range, atlas->TexWidth, atlas->TexHeight, char_idx, &dummy_x, &dummy_y, &q, 0);
dst_font->Glyphs.resize(dst_font->Glyphs.Size + 1);
ImFont::Glyph& glyph = dst_font->Glyphs.back();
@ -1514,7 +1520,7 @@ bool ImFontAtlas::Build()
if (cfg.PixelSnapH)
glyph.XAdvance = (float)(int)(glyph.XAdvance + 0.5f);
dst_font->MetricsTotalSurface += (int)((glyph.U1 - glyph.U0) * TexWidth + 1.99f) * (int)((glyph.V1 - glyph.V0) * TexHeight + 1.99f); // +1 to account for average padding, +0.99 to round
dst_font->MetricsTotalSurface += (int)((glyph.U1 - glyph.U0) * atlas->TexWidth + 1.99f) * (int)((glyph.V1 - glyph.V0) * atlas->TexHeight + 1.99f); // +1 to account for average padding, +0.99 to round
}
}
cfg.DstFont->BuildLookupTable();
@ -1526,7 +1532,7 @@ bool ImFontAtlas::Build()
ImGui::MemFree(tmp_array);
// Render into our custom data block
ImFontAtlasBuildRenderDefaultTexData(this);
ImFontAtlasBuildRenderDefaultTexData(atlas);
return true;
}

1
imgui_internal.h
View File

@ -793,6 +793,7 @@ namespace ImGui
} // namespace ImGui
// ImFontAtlas internals
IMGUI_API bool ImFontAtlasBuildWithStbTruetype(ImFontAtlas* atlas);
IMGUI_API void ImFontAtlasBuildRegisterDefaultCustomRects(ImFontAtlas* atlas);
IMGUI_API void ImFontAtlasBuildSetupFont(ImFontAtlas* atlas, ImFont* font, ImFontConfig* font_config, float ascent, float descent);
IMGUI_API void ImFontAtlasBuildPackCustomRects(ImFontAtlas* atlas, void* spc);