first pass at standing up freetype font provider backend

build.sh

@@ -19,7 +19,7 @@ git_hash=$(git rev-parse HEAD)
 git_hash_full=$(git rev-parse HEAD)
 
 # --- Compile/Link Line Definitions -------------------------------------------
-clang_common="-I../src/ -I../local/ -g -DBUILD_GIT_HASH=\"$git_hash\" -DBUILD_GIT_HASH_FULL=\"$git_hash_full\" -Wno-unknown-warning-option -fdiagnostics-absolute-paths -Wall -Wno-missing-braces -Wno-unused-function -Wno-writable-strings -Wno-unused-value -Wno-unused-variable -Wno-unused-local-typedef -Wno-deprecated-register -Wno-deprecated-declarations -Wno-unused-but-set-variable -Wno-single-bit-bitfield-constant-conversion -Wno-compare-distinct-pointer-types -Wno-initializer-overrides -Wno-incompatible-pointer-types-discards-qualifiers -Wno-for-loop-analysis -Xclang -flto-visibility-public-std -D_USE_MATH_DEFINES -Dstrdup=_strdup -Dgnu_printf=printf"
+clang_common="-I../src/ -I/usr/include/freetype2/ -I../local/ -g -DBUILD_GIT_HASH=\"$git_hash\" -DBUILD_GIT_HASH_FULL=\"$git_hash_full\" -Wno-unknown-warning-option -fdiagnostics-absolute-paths -Wall -Wno-missing-braces -Wno-unused-function -Wno-writable-strings -Wno-unused-value -Wno-unused-variable -Wno-unused-local-typedef -Wno-deprecated-register -Wno-deprecated-declarations -Wno-unused-but-set-variable -Wno-single-bit-bitfield-constant-conversion -Wno-compare-distinct-pointer-types -Wno-initializer-overrides -Wno-incompatible-pointer-types-discards-qualifiers -Wno-for-loop-analysis -Xclang -flto-visibility-public-std -D_USE_MATH_DEFINES -Dstrdup=_strdup -Dgnu_printf=printf"
 clang_debug="$compiler -g -O0 -DBUILD_DEBUG=1 ${clang_common} ${auto_compile_flags}"
 clang_release="$compiler -g -O2 -DBUILD_DEBUG=0 ${clang_common} ${auto_compile_flags}"
 clang_link="-lpthread -lm -lrt -ldl"
@@ -34,6 +34,7 @@ gcc_out="-o"
 link_dll="-fPIC"
 link_os_gfx="-lX11 -lXext"
 link_render="-lGL -lEGL"
+link_font_provider="-lfreetype"
 
 # --- Choose Compile/Link Lines -----------------------------------------------
 if [ -v gcc ];     then compile_debug="$gcc_debug"; fi
@@ -63,7 +64,7 @@ fi
 
 # --- Build Everything (@build_targets) ---------------------------------------
 cd build
-if [ -v raddbg ];                then didbuild=1 && $compile ../src/raddbg/raddbg_main.c                                    $compile_link $link_os_gfx $link_render $out raddbg; fi
+if [ -v raddbg ];                then didbuild=1 && $compile ../src/raddbg/raddbg_main.c                                    $compile_link $link_os_gfx $link_render $link_font_provider $out raddbg; fi
 if [ -v radlink ];               then didbuild=1 && $compile ../src/linker/lnk.c                                            $compile_link $out radlink; fi
 if [ -v rdi_from_pdb ];          then didbuild=1 && $compile ../src/rdi_from_pdb/rdi_from_pdb_main.c                        $compile_link $out rdi_from_pdb; fi
 if [ -v rdi_from_dwarf ];        then didbuild=1 && $compile ../src/rdi_from_dwarf/rdi_from_dwarf.c                         $compile_link $out rdi_from_dwarf; fi

src/draw/draw.c

@@ -574,7 +574,7 @@ dr_truncated_fancy_run_list(Vec2F32 p, DR_FRunList *list, F32 max_x, FNT_Run tra
       if(!r_handle_match(texture, r_handle_zero()))
       {
         dr_img(dst, src, texture, fr->color, 0, 0, 0);
-        //dr_rect(dst, v4f32(0, 1, 0, 0.5f), 0, 1.f, 0.f);
+        // dr_rect(dst, v4f32(0, 1, 0, 0.5f), 0, 1.f, 0.f);
       }
       advance += piece->advance;
       pixel_range.min = Min(pre_advance, pixel_range.min);

src/font_provider/freetype/font_provider_freetype.c

@@ -1,44 +1,147 @@
 // Copyright (c) 2024 Epic Games Tools
 // Licensed under the MIT license (https://opensource.org/license/mit/)
 
+////////////////////////////////
+//~ rjf: Helpers
+
+internal FP_FT_Font
+fp_ft_font_from_handle(FP_Handle handle)
+{
+  FP_FT_Font result = {(FT_Face)handle.u64[0]};
+  return result;
+}
+
+internal FP_Handle
+fp_ft_handle_from_font(FP_FT_Font font)
+{
+  FP_Handle result = {(U64)font.face};
+  return result;
+}
+
 ////////////////////////////////
 //~ rjf: Backend Implementations
 
 fp_hook void
 fp_init(void)
 {
-  
+  Arena *arena = arena_alloc();
+  fp_ft_state = push_array(arena, FP_FT_State, 1);
+  fp_ft_state->arena = arena;
+  FT_Init_FreeType(&fp_ft_state->library);
 }
 
 fp_hook FP_Handle
 fp_font_open(String8 path)
 {
-  FP_Handle f = {0};
-  return f;
+  Temp scratch = scratch_begin(0, 0);
+  String8 path_copy = push_str8_copy(scratch.arena, path);
+  FP_FT_Font font = {0};
+  FT_New_Face(fp_ft_state->library, (char *)path_copy.str, 0, &font.face);
+  FP_Handle handle = fp_ft_handle_from_font(font);
+  scratch_end(scratch);
+  return handle;
 }
 
 fp_hook FP_Handle
 fp_font_open_from_static_data_string(String8 *data_ptr)
 {
-  FP_Handle f = {0};
-  return f;
+  FP_FT_Font font = {0};
+  FT_New_Memory_Face(fp_ft_state->library, data_ptr->str, (FT_Long)data_ptr->size, 0, &font.face);
+  FP_Handle handle = fp_ft_handle_from_font(font);
+  return handle;
 }
 
 fp_hook void
 fp_font_close(FP_Handle handle)
 {
+  FP_FT_Font font = fp_ft_font_from_handle(handle);
+  if(font.face != 0)
+  {
+    FT_Done_Face(font.face);
+  }
 }
 
 fp_hook FP_Metrics
-fp_metrics_from_font(FP_Handle font)
+fp_metrics_from_font(FP_Handle handle)
 {
-  FP_Metrics m = {0};
-  return m;
+  FP_FT_Font font = fp_ft_font_from_handle(handle);
+  FP_Metrics result = {0};
+  if(font.face != 0)
+  {
+    result.design_units_per_em = (F32)font.face->units_per_EM;
+    result.ascent              = (F32)font.face->ascender;
+    result.descent             = (F32)font.face->descender;
+    result.line_gap            = (F32)(font.face->height - font.face->ascender + font.face->descender);
+    result.capital_height      = (F32)(font.face->ascender + font.face->descender);
+  }
+  return result;
 }
 
-fp_hook NO_ASAN FP_RasterResult
-fp_raster(Arena *arena, FP_Handle font, F32 size, FP_RasterFlags flags, String8 string)
+fp_hook FP_RasterResult
+fp_raster(Arena *arena, FP_Handle handle, F32 size, FP_RasterFlags flags, String8 string)
 {
-  FP_RasterResult r = {0};
-  return r;
+  ProfBeginFunction();
+  FP_FT_Font font = fp_ft_font_from_handle(handle);
+  FP_RasterResult result = {0};
+  if(font.face != 0)
+  {
+    Temp scratch = scratch_begin(&arena, 1);
+    
+    //- rjf: unpack font
+    FT_Face face = font.face;
+    FT_Set_Pixel_Sizes(face, 0, (FT_UInt)size);
+    S64 ascent  = face->size->metrics.ascender >> 6;
+    S64 descent = abs_s64(face->size->metrics.descender >> 6);
+    S64 height  = face->size->metrics.height >> 6;
+    
+    //- rjf: unpack string
+    String32 string32 = str32_from_8(scratch.arena, string);
+    
+    //- rjf: measure
+    S32 total_width = 0;
+    for EachIndex(idx, string32.size)
+    {
+      FT_Load_Char(face, string32.str[idx], FT_LOAD_RENDER);
+      total_width += (face->glyph->advance.x >> 6);
+    }
+    
+    //- rjf: allocate & fill atlas w/ rasterization
+    Vec2S16 dim = {(S16)total_width+1, height+1};
+    U64 atlas_size = dim.x * dim.y * 4;
+    U8 *atlas = push_array(arena, U8, atlas_size);
+    S32 baseline = ascent;
+    S32 atlas_write_x = 0;
+    for EachIndex(idx, string32.size)
+    {
+      FT_Load_Char(face, string32.str[idx], FT_LOAD_RENDER);
+      FT_Bitmap *bmp = &face->glyph->bitmap;
+      S32 top = face->glyph->bitmap_top;
+      S32 left = face->glyph->bitmap_left;
+      for(S32 row = 0; row < (S32)bmp->rows; row += 1)
+      {
+        S32 y = baseline - top + row;
+        for(S32 col = 0; col < (S32)bmp->width; col += 1)
+        {
+          S32 x = atlas_write_x + left + col;
+          U64 off = (y*dim.x + x)*4;
+          if(off+4 <= atlas_size)
+          {
+            atlas[off+0] = 255;
+            atlas[off+1] = 255;
+            atlas[off+2] = 255;
+            atlas[off+3] = bmp->buffer[row*bmp->pitch + col];
+          }
+        }
+      }
+      atlas_write_x += (face->glyph->advance.x >> 6);
+    }
+    
+    //- rjf: fill result
+    result.atlas_dim = dim;
+    result.advance   = (F32)total_width;
+    result.atlas     = atlas;
+    scratch_end(scratch);
+  }
+  ProfEnd();
+  return result;
 }

src/font_provider/freetype/font_provider_freetype.h

@@ -4,4 +4,40 @@
 #ifndef FONT_PROVIDER_FREETYPE_H
 #define FONT_PROVIDER_FREETYPE_H
 
+////////////////////////////////
+//~ rjf: Freetype Includes
+
+#undef internal
+#include <ft2build.h>
+#include FT_FREETYPE_H
+#include FT_GLYPH_H
+#define internal static
+
+////////////////////////////////
+//~ rjf: State Types
+
+typedef struct FP_FT_Font FP_FT_Font;
+struct FP_FT_Font
+{
+  FT_Face face;
+};
+
+typedef struct FP_FT_State FP_FT_State;
+struct FP_FT_State
+{
+  Arena *arena;
+  FT_Library library;
+};
+
+////////////////////////////////
+//~ rjf: Globals
+
+global FP_FT_State *fp_ft_state = 0;
+
+////////////////////////////////
+//~ rjf: Helpers
+
+internal FP_FT_Font fp_ft_font_from_handle(FP_Handle handle);
+internal FP_Handle fp_ft_handle_from_font(FP_FT_Font font);
+
 #endif // FONT_PROVIDER_FREETYPE_H

src/render/opengl/render_opengl.c

@@ -468,7 +468,7 @@ r_window_submit(OS_Handle window, R_Handle window_equip, R_PassList *passes)
       {
         R_PassParams_Blur *params = pass->params_blur;
         GLuint shader = r_ogl_state->shaders[R_OGL_ShaderKind_Blur];
-        glBindVertexArrayScope(r_ogl_state->all_purpose_vao) glUseProgramScope(shader)
+        // TODO(rjf): glBindVertexArrayScope(r_ogl_state->all_purpose_vao) glUseProgramScope(shader)
         {
           // TODO(rjf)
         }