add text_style_t, draw-text.c

1 files changed, 130 insertions, 0 deletions

diff --git a/src/sdl/draw-text.c b/src/sdl/draw-text.c
new file mode 100644
index 0000000..0e58949
--- /dev/null
+++ b/src/sdl/draw-text.c
@@ -0,0 +1,130 @@
+#include "draw-text.h"
+#include "util.h"
+
+static SDL_Rect
+text_get_rect(
+  SDL_Renderer * const renderer,
+  TTF_Font * const font,
+  const text_style_t * const style,
+  const char * const buf
+) {
+  // get renderer size
+  int renderer_w, renderer_h;
+  if (SDL_GetRendererOutputSize(renderer, &renderer_w, &renderer_h)) {
+    die("SDL_GetRendererOutputSize(): %s", SDL_GetError());
+  }
+
+  // get text size
+  int text_w, text_h;
+  if (TTF_SizeText(font, buf, &text_w, &text_h)) {
+    die("TTF_SizeText(): %s", TTF_GetError());
+  }
+
+  // build rect
+  switch (style->align) {
+  case TEXT_ALIGN_TOP_LEFT:
+    return (SDL_Rect) { 
+      .x = style->pad.x,
+      .y = style->pad.y,
+      .w = text_w,
+      .h = text_h,
+    };
+  case TEXT_ALIGN_TOP_CENTER:
+    return (SDL_Rect) {
+      .x = (renderer_w - text_w) / 2 + style->pad.x,
+      .y = style->pad.y,
+      .w = text_w,
+      .h = text_h,
+    };
+  case TEXT_ALIGN_TOP_RIGHT:
+    return (SDL_Rect) {
+      .x = renderer_w - text_w - style->pad.x,
+      .y = style->pad.y,
+      .w = text_w,
+      .h = text_h,
+    };
+  case TEXT_ALIGN_CENTER_LEFT:
+    return (SDL_Rect) {
+      .x = style->pad.x,
+      .y = (renderer_h - text_h) / 2 + style->pad.y,
+      .w = text_w,
+      .h = text_h,
+    };
+  case TEXT_ALIGN_CENTER_CENTER:
+    return (SDL_Rect) {
+      .x = (renderer_w - text_w) / 2 + style->pad.x,
+      .y = (renderer_h - text_h) / 2 + style->pad.y,
+      .w = text_w,
+      .h = text_h,
+    };
+  case TEXT_ALIGN_CENTER_RIGHT:
+    return (SDL_Rect) {
+      .x = renderer_w - text_w - style->pad.x,
+      .y = (renderer_h - text_h) / 2 + style->pad.y,
+      .w = text_w,
+      .h = text_h,
+    };
+  case TEXT_ALIGN_BOTTOM_LEFT:
+    return (SDL_Rect) {
+      .x = style->pad.x,
+      .y = renderer_h - text_h - style->pad.y,
+      .w = text_w,
+      .h = text_h,
+    };
+  case TEXT_ALIGN_BOTTOM_CENTER:
+    return (SDL_Rect) {
+      .x = (renderer_w - text_w) / 2 + style->pad.x,
+      .y = renderer_h - text_h - style->pad.y,
+      .w = text_w,
+      .h = text_h,
+    };
+  case TEXT_ALIGN_BOTTOM_RIGHT:
+    return (SDL_Rect) {
+      .x = renderer_w - text_w - style->pad.x,
+      .y = renderer_h - text_h - style->pad.y,
+      .w = text_w,
+      .h = text_h,
+    };
+  default:
+    return (SDL_Rect) {
+      .x = style->pad.x,
+      .y = style->pad.y,
+      .w = text_w,
+      .h = text_h,
+    };
+  }
+}
+
+void
+draw_text(
+  SDL_Renderer * const renderer,
+  TTF_Font * const font,
+  const text_style_t * const style,
+  const char * const buf
+) {
+  // get rect
+  const SDL_Rect rect = text_get_rect(renderer, font, style, buf);
+
+  // create surface, check for error
+  SDL_Surface *surface = TTF_RenderText_Shaded(font, buf, style->colors[0], style->colors[1]);
+  if (!surface) {
+    die("TTF_RenderText_Blended(): %s", TTF_GetError());
+  }
+
+  // create texture, check for error
+  SDL_Texture *texture = SDL_CreateTextureFromSurface(renderer, surface);
+  if (!texture) {
+    die("SDL_CreateTextureFromSurface(): %s", SDL_GetError());
+  }
+
+  // free surface
+  SDL_FreeSurface(surface);
+
+  // render text
+  if (SDL_RenderCopy(renderer, texture, NULL, &rect)) {
+    die("SDL_RenderCopy(): %s", SDL_GetError());
+  }
+
+  // free texture
+  SDL_DestroyTexture(texture);
+}