Text.c

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/*
 * ObjectivelyMVC: Object oriented MVC framework for SDL3 and C.
 * Copyright (C) 2014 Jay Dolan <jay@jaydolan.com>
 *
 * This software is provided 'as-is', without any express or implied
 * warranty. In no event will the authors be held liable for any damages
 * arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 * claim that you wrote the original software. If you use this software
 * in a product, an acknowledgment in the product documentation would be
 * appreciated but is not required.
 *
 * 2. Altered source versions must be plainly marked as such, and must not be
 * misrepresented as being the original software.
 *
 * 3. This notice may not be removed or altered from any source distribution.
 */
 
#include <assert.h>
#include <math.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
 
#include "Colors.h"
#include "Text.h"
 
static inline float view_pixel_density(SDL_Window *window) {
  return window ? SDL_GetWindowPixelDensity(window) : 1.0f;
}
 
#define _Class _Text
 
#pragma mark - Color Escape Sequences
 
SDL_Color TextEscapeColors[] = {
  { 0x00, 0x00, 0x00, 0xFF },  // ^0 Black
  { 0xFF, 0x00, 0x00, 0xFF },  // ^1 Red
  { 0x00, 0xFF, 0x00, 0xFF },  // ^2 Green
  { 0xFF, 0xFF, 0x00, 0xFF },  // ^3 Yellow
  { 0x00, 0x00, 0xFF, 0xFF },  // ^4 Blue
  { 0xFF, 0x00, 0xFF, 0xFF },  // ^5 Magenta
  { 0x00, 0xFF, 0xFF, 0xFF },  // ^6 Cyan
  { 0xFF, 0xFF, 0xFF, 0xFF },  // ^7 White
  { 0xFF, 0x80, 0x00, 0xFF },  // ^8 Orange
  { 0x80, 0x80, 0x80, 0xFF }   // ^9 Grey
};
 
static char *stripColors(const char *text) {
 
  assert(text);
 
  char *stripped = malloc(strlen(text) + 1);
  int idx = 0;
 
  for (const char *p = text; *p; p++) {
    if (p[0] == '^' && p[1] >= '0' && p[1] <= '9') {
      p++;
    } else {
      stripped[idx++] = *p;
    }
  }
 
  stripped[idx] = '\0';
  return stripped;
}
 
typedef struct {
  SDL_Rect rect;
  SDL_Color color;
} CharInfo;
 
static void colorize(SDL_Surface *surface, const CharInfo *info, float scale) {
 
  const float fx = floorf(info->rect.x * scale);
  const float fy = floorf(info->rect.y * scale);
  const float fw = ceilf(info->rect.w * scale);
  const float fh = ceilf(info->rect.h * scale);
 
  int x = (int) fx - 1;
  int y = (int) fy - 1;
  int w = (int) fw + 2;
  int h = (int) fh + 2;
 
  if (w <= 0 || h <= 0) {
    return;
  }
 
  if (x < 0) { w += x; x = 0; }
  if (y < 0) { h += y; y = 0; }
 
  uint32_t *pixels = (uint32_t *) surface->pixels;
  const int pitch = surface->pitch / 4;
  const SDL_Color color = info->color;
 
  for (int row = y; row < y + h && row < surface->h; row++) {
    for (int col = x; col < x + w && col < surface->w; col++) {
      SDL_Color *c = (SDL_Color *) &pixels[row * pitch + col];
      c->r = (int) (c->r * color.r / 255.0f);
      c->g = (int) (c->g * color.g / 255.0f);
      c->b = (int) (c->b * color.b / 255.0f);
    }
  }
}
 
static CharInfo *buildCharInfo(const Font *font, const char *text,
                               SDL_Color defaultColor, int wrapWidth, int *outCount) {
 
  if (!text || !*text) {
    *outCount = 0;
    return NULL;
  }
 
  char *stripped = stripColors(text);
  if (!stripped || !*stripped) {
    free(stripped);
    *outCount = 0;
    return NULL;
  }
 
  const size_t strippedLen = strlen(stripped);
  CharInfo *chars = malloc(sizeof(CharInfo) * strippedLen);
 
  const int scaledWrapWidth = wrapWidth ? (int) (wrapWidth * font->scale) : 0;
 
  int lineHeight;
  $(font, sizeCharacters, "A", NULL, &lineHeight);
 
  SDL_Color currentColor = defaultColor;
  int charIdx = 0;
  int lineStartByte = 0;
  int prevH = 0;
 
  for (const char *p = text; *p; p++) {
    if (p[0] == '^' && p[1] >= '0' && p[1] <= '9') {
      currentColor = TextEscapeColors[p[1] - '0'];
      p++;
      continue;
    }
 
    int currH;
    if (scaledWrapWidth) {
      TTF_GetStringSizeWrapped(font->font, stripped, charIdx + 1, scaledWrapWidth, NULL, &currH);
    } else {
      TTF_GetStringSize(font->font, stripped, charIdx + 1, NULL, &currH);
    }
 
    if (currH > prevH) {
      lineStartByte = charIdx;
      prevH = currH;
    }
 
    int lineX = 0;
    if (charIdx > lineStartByte) {
      TTF_GetStringSize(font->font, stripped + lineStartByte, charIdx - lineStartByte, &lineX, NULL);
    }
 
    int charW;
    TTF_GetStringSize(font->font, stripped + charIdx, 1, &charW, NULL);
 
    chars[charIdx].rect.x = (int) (lineX / font->scale);
    chars[charIdx].rect.y = (int) (currH / font->scale) - lineHeight;
    chars[charIdx].rect.w = (int) (charW / font->scale);
    chars[charIdx].rect.h = lineHeight;
    chars[charIdx].color = currentColor;
 
    charIdx++;
  }
 
  free(stripped);
  *outCount = charIdx;
  return chars;
}
 
static SDL_Surface *renderWithColorEscapes(const Text *self, int wrapWidth) {
 
  char *stripped = stripColors(self->text);
  SDL_Surface *surface = $(self->font, renderCharacters, stripped, self->color, wrapWidth);
  free(stripped);
 
  if (!surface) {
    return NULL;
  }
 
  int charCount = 0;
  CharInfo *charInfo = buildCharInfo(self->font, self->text, self->color, wrapWidth, &charCount);
 
  if (charInfo) {
    SDL_LockSurface(surface);
    for (int i = 0; i < charCount; i++) {
      colorize(surface, &charInfo[i], self->font->scale);
    }
    SDL_UnlockSurface(surface);
    free(charInfo);
  }
 
  return surface;
}
 
static void sizeWithColorEscapes(const Text *self, int *w, int *h) {
 
  char *stripped = stripColors(self->text ?: "");
  $(self->font, sizeCharacters, stripped, w, h);
  free(stripped);
}
 
#pragma mark - ObjectInterface
 
static void dealloc(Object *self) {
 
  Text *this = (Text *) self;
 
  release(this->font);
 
  free(this->text);
 
  this->texture = release(this->texture);
 
  super(Object, self, dealloc);
}
 
static String *description(const Object *self) {
 
  View *this = (View *) self;
  const SDL_Rect bounds = $(this, bounds);
 
  String *classNames = $((Object *) this->classNames, description);
  String *description = str("%s@%p \"%s\" %s [%d, %d, %d, %d]",
                this->identifier ?: classnameof(self),
                self,
                ((Text *) self)->text,
                classNames->chars,
                bounds.x, bounds.y, bounds.w, bounds.h);
 
  release(classNames);
  return description;
}
 
#pragma mark - View
 
static void applyStyle(View *self, const Style *style) {
 
  super(View, self, applyStyle, style);
 
  Text *this = (Text *) self;
 
  const Inlet colorInlets[] = MakeInlets(
    MakeInlet("color", InletTypeColor, &this->color, NULL)
  );
 
  if ($(self, bind, colorInlets, style->attributes)) {
    this->texture = release(this->texture);
    this->textureSize = MakeSize(0, 0);
  }
 
  char *fontFamily = NULL;
  int fontSize = -1, fontStyle = -1;
 
  const Inlet fontInlets[] = MakeInlets(
    MakeInlet("font-family", InletTypeCharacters, &fontFamily, NULL),
    MakeInlet("font-size", InletTypeInteger, &fontSize, NULL),
    MakeInlet("font-style", InletTypeEnum, &fontStyle, (ident) FontStyleNames)
  );
 
  if ($(self, bind, fontInlets, style->attributes)) {
 
    Font *font = $$(Font, cachedFont, fontFamily , fontSize, fontStyle);
    assert(font);
 
    $(this, setFont, font);
 
    if (fontFamily) {
      free(fontFamily);
    }
  }
}
 
static void awakeWithDictionary(View *self, const Dictionary *dictionary) {
 
  super(View, self, awakeWithDictionary, dictionary);
 
  Text *this = (Text *) self;
 
  const Inlet inlets[] = MakeInlets(
    MakeInlet("color", InletTypeColor, &this->color, NULL),
    MakeInlet("colorEscapes", InletTypeBool, &this->colorEscapes, NULL),
    MakeInlet("font", InletTypeFont, &this->font, NULL),
    MakeInlet("lineWrap", InletTypeBool, &this->lineWrap, NULL),
    MakeInlet("text", InletTypeCharacters, &this->text, NULL)
  );
 
  $(self, bind, inlets, dictionary);
 
  $(self, sizeToFit);
}
 
static View *init(View *self) {
  return (View *) $((Text *) self, initWithText, NULL, NULL);
}
 
static void render(View *self, Renderer *renderer) {
 
  super(View, self, render, renderer);
 
  Text *this = (Text *) self;
 
  assert(this->font);
 
  const float scale = view_pixel_density(self->window);
 
  if (this->font->scale != scale) {
    this->font->scale = scale;
    $(this->font, renderDeviceDidReset);
    this->texture = release(this->texture);
    this->textureSize = MakeSize(0, 0);
  }
 
  if (this->text) {
 
    const SDL_Rect frame = $(self, renderFrame);
 
    if (this->texture == NULL) {
      SDL_Surface *surface;
 
      if (this->colorEscapes) {
        surface = renderWithColorEscapes(this, this->lineWrap ? frame.w : 0);
      } else {
        surface = $(this->font, renderCharacters,
                    this->text,
                    this->color,
                    this->lineWrap ? frame.w : 0);
      }
 
      assert(surface);
 
      const float textureWidth = roundf(surface->w / scale);
      const float textureHeight = roundf(surface->h / scale);
 
      this->textureSize.w = (int) textureWidth;
      this->textureSize.h = (int) textureHeight;
 
      SDL_Surface *upload = surface;
      SDL_Surface *converted = NULL;
 
      if (SDL_BYTESPERPIXEL(surface->format) == 1) {
        converted = SDL_CreateSurface(surface->w, surface->h, SDL_PIXELFORMAT_RGBA32);
        assert(converted);
        const SDL_PixelFormatDetails *details = SDL_GetPixelFormatDetails(SDL_PIXELFORMAT_RGBA32);
        assert(details);
        const Uint8 *src = (const Uint8 *) surface->pixels;
        Uint32 *dst = (Uint32 *) converted->pixels;
        for (int y = 0; y < surface->h; y++) {
          for (int x = 0; x < surface->w; x++) {
            const Uint8 a = src[y * surface->pitch + x];
            dst[y * surface->w + x] = SDL_MapRGBA(details, NULL, 255, 255, 255, a);
          }
        }
        upload = converted;
      } else if (surface->format != SDL_PIXELFORMAT_RGBA32) {
        converted = SDL_ConvertSurface(surface, SDL_PIXELFORMAT_RGBA32);
        assert(converted);
        upload = converted;
      }
 
      const SDL_GPUTextureCreateInfo texInfo = {
        .type                 = SDL_GPU_TEXTURETYPE_2D,
        .format               = SDL_GPU_TEXTUREFORMAT_R8G8B8A8_UNORM,
        .usage                = SDL_GPU_TEXTUREUSAGE_SAMPLER,
        .width                = (Uint32) upload->w,
        .height               = (Uint32) upload->h,
        .layer_count_or_depth = 1,
        .num_levels           = 1,
      };
 
      this->texture = $(renderer->device, createTexture, &texInfo, upload->pixels);
 
      if (converted) {
        SDL_DestroySurface(converted);
      }
 
      SDL_DestroySurface(surface);
    }
 
    assert(this->texture);
 
    const SDL_Rect draw_rect = { frame.x, frame.y, this->textureSize.w, this->textureSize.h };
    $(renderer, drawTexture, this->texture, &draw_rect, &Colors.White);
  }
}
 
static void renderDeviceDidReset(View *self) {
 
  Text *this = (Text *) self;
 
  this->font->scale = view_pixel_density(self->window);
  $(this->font, renderDeviceDidReset);
 
  super(View, self, renderDeviceDidReset);
}
 
static void renderDeviceWillReset(View *self) {
 
  Text *this = (Text *) self;
 
  this->texture = release(this->texture);
  this->textureSize = MakeSize(0, 0);
 
  super(View, self, renderDeviceWillReset);
}
 
static SDL_Size sizeThatFits(const View *self) {
  return $((Text *) self, naturalSize);
}
 
#pragma mark - Text
 
static Text *initWithText(Text *self, const char *text, Font *font) {
 
  self = (Text *) super(View, self, initWithFrame, NULL);
  if (self) {
    $(self, setFont, font);
    $(self, setText, text);
  }
 
  return self;
}
 
static SDL_Size naturalSize(const Text *self) {
 
  SDL_Size size = MakeSize(0, 0);
 
  if (self->font) {
    const char *text = self->text ?: "";
 
    if (self->colorEscapes) {
      sizeWithColorEscapes(self, &size.w, &size.h);
    } else {
      $(self->font, sizeCharacters, text, &size.w, &size.h);
    }
  }
 
  return size;
}
 
static void setFont(Text *self, Font *font) {
 
  font = font ?: $$(Font, defaultFont);
 
  if (font != self->font) {
 
    release(self->font);
    self->font = retain(font);
 
    self->texture = release(self->texture);
    self->textureSize = MakeSize(0, 0);
 
    $((View *) self, sizeToFit);
  }
}
 
static void setText(Text *self, const char *text) {
 
  if (strcmp(self->text ?: "", text ?: "")) {
 
    free(self->text);
 
    if (text && strlen(text)) {
      self->text = strdup(text);
    } else {
      self->text = NULL;
    }
 
    self->texture = release(self->texture);
    self->textureSize = MakeSize(0, 0);
 
    $((View *) self, sizeToFit);
  }
}
 
static void setTextWithFormat(Text *self, const char *fmt, ...) {
 
  va_list args;
  va_start(args, fmt);
 
  char *text;
  const int len = vasprintf(&text, fmt, args);
  if (len >= 0) {
    $(self, setText, text);
  }
 
  free(text);
  va_end(args);
}
 
#pragma mark - Class lifecycle
 
static void initialize(Class *clazz) {
 
  ((ObjectInterface *) clazz->interface)->dealloc = dealloc;
  ((ObjectInterface *) clazz->interface)->description = description;
 
  ((ViewInterface *) clazz->interface)->applyStyle = applyStyle;
  ((ViewInterface *) clazz->interface)->awakeWithDictionary = awakeWithDictionary;
  ((ViewInterface *) clazz->interface)->init = init;
  ((ViewInterface *) clazz->interface)->render = render;
  ((ViewInterface *) clazz->interface)->renderDeviceDidReset = renderDeviceDidReset;
  ((ViewInterface *) clazz->interface)->renderDeviceWillReset = renderDeviceWillReset;
  ((ViewInterface *) clazz->interface)->sizeThatFits = sizeThatFits;
 
  ((TextInterface *) clazz->interface)->initWithText = initWithText;
  ((TextInterface *) clazz->interface)->naturalSize = naturalSize;
  ((TextInterface *) clazz->interface)->setFont = setFont;
  ((TextInterface *) clazz->interface)->setText = setText;
  ((TextInterface *) clazz->interface)->setTextWithFormat = setTextWithFormat;
}
 
Class *_Text(void) {
  static Class *clazz;
  static Once once;
 
  do_once(&once, {
    clazz = _initialize(&(const ClassDef) {
      .name = "Text",
      .superclass = _View(),
      .instanceSize = sizeof(Text),
      .interfaceOffset = offsetof(Text, interface),
      .interfaceSize = sizeof(TextInterface),
      .initialize = initialize,
    });
  });
 
  return clazz;
}
 
#undef _Class