Merge pull request #19 from Free-Pascal-meets-SDL-Website/add-sdl3-ttf

Add SDL3_ttf unit

Author: Free-Pascal-meets-SDL-Website

units/SDL3_textengine.pas

@@ -0,0 +1,204 @@
+unit SDL3_textengine;
+
+{
+  This file is part of:
+
+    SDL3 for Pascal
+    (https://github.com/PascalGameDevelopment/SDL3-for-Pascal)
+    SPDX-License-Identifier: Zlib
+}
+
+{$DEFINE SDL_TTF_TEXTENGINE}
+
+{$I sdl.inc}
+
+interface
+
+{$IFDEF WINDOWS}
+  uses
+    SDL3,
+    SDL3_ttf,
+    {$IFDEF FPC}
+    ctypes,
+    {$ENDIF}
+    Windows;
+{$ENDIF}
+
+{$IF DEFINED(UNIX) AND NOT DEFINED(ANDROID)}
+  uses
+    SDL3,
+    SDL3_ttf,
+    {$IFDEF FPC}
+    ctypes,
+    UnixType,
+    {$ENDIF}
+    {$IFDEF DARWIN}
+    CocoaAll;
+    {$ELSE}
+    X,
+    XLib;
+    {$ENDIF}
+{$ENDIF}
+
+{$IF DEFINED(UNIX) AND DEFINED(ANDROID) AND DEFINED(FPC)}
+  uses
+    SDL3,
+    SDL3_ttf,
+    ctypes,
+    UnixType;
+{$ENDIF}
+
+{*
+ *  \file SDL_textengine.h
+ *
+ * Definitions for implementations of the TTF_TextEngine interface.
+  }
+
+{ #note : SDL3-for-Pascal: Based on file SDL_textengine.h version 3.1.0 (preview). }
+
+{*
+ * A font atlas draw command.
+ *
+ * \since This enum is available since SDL_ttf 3.0.0.
+  }
+type
+  PPTTF_DrawCommand = ^PTTF_DrawCommand;
+  PTTF_DrawCommand = ^TTTF_DrawCommand;
+  TTTF_DrawCommand = type Integer;
+const
+  TTF_DRAW_COMMAND_NOOP  = TTTF_DrawCommand(0);
+  TTF_DRAW_COMMAND_FILL  = TTTF_DrawCommand(1);
+  TTF_DRAW_COMMAND_COPY  = TTTF_DrawCommand(2);
+
+{*
+ * A filled rectangle draw operation.
+ *
+ * \since This struct is available since SDL_ttf 3.0.0.
+ *
+ * \sa TTF_DrawOperation
+  }
+type
+  PPTTF_FillOperation = ^PTTF_FillOperation;
+  PTTF_FillOperation = ^TTTF_FillOperation;
+  TTTF_FillOperation = record
+      cmd: TTTF_DrawCommand; {*< TTF_DRAW_COMMAND_FILL  }
+      rect: TSDL_Rect;       {*< The rectangle to fill, in pixels. The x coordinate is relative to the left side of the text area, going right, and the y coordinate is relative to the top side of the text area, going down.  }
+    end;
+
+{*
+ * A texture copy draw operation.
+ *
+ * \since This struct is available since SDL_ttf 3.0.0.
+ *
+ * \sa TTF_DrawOperation
+  }
+type
+  PPTTF_CopyOperation = ^PTTF_CopyOperation;
+  PTTF_CopyOperation = ^TTTF_CopyOperation;
+  TTTF_CopyOperation = record
+      cmd: TTTF_DrawCommand; {*< TTF_DRAW_COMMAND_COPY  }
+      text_offset: cint;     {*< The offset in the text corresponding to this glyph.
+                                                                   There may be multiple glyphs with the same text offset
+                                                                   and the next text offset might be several Unicode codepoints
+                                                                   later. In this case the glyphs and codepoints are grouped
+                                                                   together and the group bounding box is the union of the dst
+                                                                   rectangles for the corresponding glyphs.  }
+      glyph_font: PTTF_Font; {*< The font containing the glyph to be drawn, can be passed to TTF_GetGlyphImageForIndex()  }
+      glyph_index: cuint32;  {*< The glyph index of the glyph to be drawn, can be passed to TTF_GetGlyphImageForIndex()  }
+      src: TSDL_Rect;        {*< The area within the glyph to be drawn  }
+      dst: TSDL_Rect;        {*< The drawing coordinates of the glyph, in pixels. The x coordinate is relative to the left side of the text area, going right, and the y coordinate is relative to the top side of the text area, going down.  }
+      reserved: Pointer;
+    end;
+
+{*
+ * A text engine draw operation.
+ *
+ * \since This struct is available since SDL_ttf 3.0.0.
+  }
+type
+  PPTTF_DrawOperation = ^PTTF_DrawOperation;
+  PTTF_DrawOperation = ^TTTF_DrawOperation;
+  TTTF_DrawOperation = record
+      case Integer of
+        0: (cmd: TTTF_DrawCommand);
+        1: (fill: TTTF_FillOperation);
+        2: (copy: TTTF_CopyOperation);
+      end;
+
+{ Private data in TTF_Text, to assist in text measurement and layout  }
+type
+  PPTTF_TextLayout = ^PTTF_TextLayout;
+  PTTF_TextLayout = type Pointer;
+
+{ Private data in TTF_Text, available to implementations }
+type
+  PPTTF_TextData = ^PTTF_TextData;
+  PTTF_TextData = ^TTTF_TextData;
+  TTTF_TextData = record
+      font: PTTF_Font;             {*< The font used by this text, read-only.  }
+      color: TSDL_FColor;          {*< The color of the text, read-only.  }
+
+      needs_layout_update: cbool;  {*< True if the layout needs to be updated  }
+      layout: PTTF_TextLayout;     {*< Cached layout information, read-only.  }
+      x: cint;                     {*< The x offset of the upper left corner of this text, in pixels, read-only.  }
+      y: cint;                     {*< The y offset of the upper left corner of this text, in pixels, read-only.  }
+      w: cint;                     {*< The width of this text, in pixels, read-only.  }
+      h: cint;                     {*< The height of this text, in pixels, read-only.  }
+      num_ops: cint;               {*< The number of drawing operations to render this text, read-only.  }
+      ops: PTTF_DrawOperation;     {*< The drawing operations used to render this text, read-only.  }
+      num_clusters: cint;          {*< The number of substrings representing clusters of glyphs in the string, read-only  }
+      clusters: PTTF_SubString;    {*< Substrings representing clusters of glyphs in the string, read-only  }
+
+      props: TSDL_PropertiesID;    {*< Custom properties associated with this text, read-only. This field is created as-needed using TTF_GetTextProperties() and the properties may be then set and read normally  }
+
+      needs_engine_update: cbool;  {*< True if the engine text needs to be updated  }
+      engine: PTTF_TextEngine;     {*< The engine used to render this text, read-only.  }
+      engine_text: Pointer;        {*< The implementation-specific representation of this text  }
+    end;
+
+{*
+ * A text engine interface.
+ *
+ * This structure should be initialized using SDL_INIT_INTERFACE()
+ *
+ * \since This struct is available since SDL_ttf 3.0.0.
+ *
+ * \sa SDL_INIT_INTERFACE
+  }
+type
+  PPTTF_TextEngine = ^PTTF_TextEngine;
+  PTTF_TextEngine = ^TTTF_TextEngine;
+  TTTF_TextEngine = record
+      version: cuint32;     {*< The version of this interface  }
+      userdata: Pointer;    {*< User data Pointer passed to callbacks  }
+
+      { Create a text representation from draw instructions.
+       *
+       * All fields of `text` except `internal->engine_text` will already be filled out.
+       *
+       * This function should set the `internal->engine_text` field to a non-nil value.
+       *
+       * \param userdata the userdata Pointer in this interface.
+       * \param text the text object being created.
+      }
+      CreateText: function(userdata: Pointer; text: PTTF_Text): cbool; cdecl;
+
+      {*
+       * Destroy a text representation.
+      }
+      DestroyText: procedure(userdata: Pointer; text: PTTF_Text); cdecl;
+    end;
+
+{ Check the size of TTF_TextEngine
+ *
+ * If this assert fails, either the compiler is padding to an unexpected size,
+ * or the interface has been updated and this should be updated to match and
+ * the code using this interface should be updated to handle the old version.
+  }
+{ #todo : SDL3-for-Pascal: Implement }
+// SDL_COMPILE_TIME_ASSERT(TTF_TextEngine_SIZE, ...
+
+implementation
+
+end.
+