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#include "sfont.h"
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#include "renderer.h"
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/* adorable CGA: https://en.wikipedia.org/wiki/Color_Graphics_Adapter#Color_palette */
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int cga_colors[16] = {
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0x000000,
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0x0000AA,
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0x00AA00,
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0x00AAAA,
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0xAA0000,
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0xAA00AA,
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0xAA5500,
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0xAAAAAA,
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0x555555,
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0x5555FF,
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0x55FF55,
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0x55FFFF,
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0xFF5555,
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0xFF55FF,
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0xFFFF55,
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0xFFFFFF,
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};
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typedef struct {
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unsigned char bitmap[FONT_HEIGHT];
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} rawchar_t;
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typedef struct {
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rawchar_t charset[256];
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} rawfont_t;
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sdlfont_t *read_raw_sdlfont(const char *filename) {
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rawfont_t font;
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FILE *f = fopen(filename, "r");
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fread(&font, sizeof(rawfont_t), 1, f);
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fclose(f);
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sdlfont_t *sfont = malloc(sizeof(*sfont));
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for (int i = 0; i < 256; ++i) {
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rawchar_t c = font.charset[i];
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SDL_Texture *t = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_RGBA8888, SDL_TEXTUREACCESS_TARGET, FONT_WIDTH, FONT_HEIGHT);
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SDL_SetTextureBlendMode(t, SDL_BLENDMODE_BLEND);
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SDL_SetRenderTarget(renderer, t);
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SDL_RenderClear(renderer);
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for (int row = 0; row < FONT_HEIGHT; ++row) {
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unsigned char rowdata = c.bitmap[row],
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mask = 0x80;
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for (int offset = 0; offset < FONT_WIDTH; ++offset) {
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if (rowdata & mask) {
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SDL_RenderDrawPoint(renderer, offset, row);
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}
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mask /= 2;
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}
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}
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sfont->charset[i] = t;
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}
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SDL_SetRenderTarget(renderer, NULL);
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return sfont;
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}
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void render_sfont(sdlfont_t *sfont, unsigned short pair, int x, int y) {
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int bg = cga_colors[(pair >> (8 + 4)) & 0x7],
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fg = cga_colors[(pair >> 8) & 0xf],
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character = pair & 0xff;
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SDL_SetRenderDrawColor(renderer, bg >> 16, (bg >> 8) & 0xff, bg & 0xff, SDL_ALPHA_OPAQUE);
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SDL_Rect bgrect = { x * FONT_WIDTH, y * FONT_HEIGHT, FONT_WIDTH, FONT_HEIGHT };
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SDL_RenderFillRect(renderer, &bgrect);
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SDL_Rect src = { 0, 0, FONT_WIDTH, FONT_HEIGHT };
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SDL_Rect dest = { x * FONT_WIDTH, y * FONT_HEIGHT, FONT_WIDTH, FONT_HEIGHT };
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SDL_SetTextureColorMod(sfont->charset[character], fg >> 16, (fg >> 8) & 0xff, fg & 0xff);
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SDL_RenderCopy(renderer, sfont->charset[character], &src, &dest);
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}
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void free_sdlfont(sdlfont_t *sfont) {
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for (int i = 0; i < 256; ++i) {
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SDL_DestroyTexture(sfont->charset[i]);
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}
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free(sfont);
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}
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/* vim: set sw=4 et: */
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