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fixed elli/ellib/circ/circb functions #1532
+27
-39
+27
-39
src/core/draw.c
+27
-39
src/core/draw.c
···
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}
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}
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-
static void drawEllipse(tic_mem* memory, s64 x0, s64 y0, s64 a, s64 b, u8 color, PixelFunc pix)
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static void drawEllipse(tic_mem* memory, s32 x0, s32 y0, s32 x1, s32 y1, u8 color, PixelFunc pix)
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{
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if(a <= 0) return;
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if(b <= 0) return;
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s64 a = abs(x1 - x0), b = abs(y1 - y0), b1 = b & 1; /* values of diameter */
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s64 dx = 4 * (1 - a) * b * b, dy = 4 * (b1 + 1) * a * a; /* error increment */
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s64 err = dx + dy + b1 * a * a, e2; /* error of 1.step */
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s64 aa2 = a*a*2, bb2 = b*b*2;
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if (x0 > x1) { x0 = x1; x1 += a; } /* if called with swapped pos32s */
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if (y0 > y1) y0 = y1; /* .. exchange them */
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y0 += (b + 1) / 2; y1 = y0 - b1; /* starting pixel */
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a *= 8 * a; b1 = 8 * b * b;
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do
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{
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s64 x = a, y = 0;
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s64 dx = (1-2*a)*b*b, dy = a*a;
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s64 sx = bb2*a, sy=0;
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s64 e = 0;
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while (sx >= sy)
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{
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pix(memory, (s32)(x0+x), (s32)(y0+y), color); /* I. Quadrant */
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pix(memory, (s32)(x0+x), (s32)(y0-y), color); /* II. Quadrant */
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pix(memory, (s32)(x0-x), (s32)(y0+y), color); /* III. Quadrant */
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pix(memory, (s32)(x0-x), (s32)(y0-y), color); /* IV. Quadrant */
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y++; sy += aa2; e += dy; dy += aa2;
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if(2*e+dx >0) { x--; sx -= bb2; e += dx; dx += bb2; }
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}
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}
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{
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s64 x = 0, y = b;
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s64 dx = b*b, dy = (1-2*b)*a*a;
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s64 sx = 0, sy=aa2*b;
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s64 e = 0;
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pix(memory, x1, y0, color); /* I. Quadrant */
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pix(memory, x0, y0, color); /* II. Quadrant */
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pix(memory, x0, y1, color); /* III. Quadrant */
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pix(memory, x1, y1, color); /* IV. Quadrant */
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e2 = 2 * err;
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if (e2 <= dy) { y0++; y1--; err += dy += a; } /* y step */
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if (e2 >= dx || 2 * err > dy) { x0++; x1--; err += dx += b1; } /* x step */
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} while (x0 <= x1);
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while (sy >= sx)
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{
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pix(memory, (s32)(x0+x), (s32)(y0+y), color); /* I. Quadrant */
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pix(memory, (s32)(x0+x), (s32)(y0-y), color); /* II. Quadrant */
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pix(memory, (s32)(x0-x), (s32)(y0+y), color); /* III. Quadrant */
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pix(memory, (s32)(x0-x), (s32)(y0-y), color); /* IV. Quadrant */
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x++; sx += bb2; e += dx; dx += bb2;
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if(2*e+dy >0) { y--; sy -= aa2; e += dy; dy += aa2; }
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}
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while (y0-y1 < b)
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{ /* too early stop of flat ellipses a=1 */
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pix(memory, x0 - 1, y0, color); /* -> finish tip of ellipse */
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pix(memory, x1 + 1, y0++, color);
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pix(memory, x0 - 1, y1, color);
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pix(memory, x1 + 1, y1--, color);
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}
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}
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···
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void tic_api_circ(tic_mem* memory, s32 x, s32 y, s32 r, u8 color)
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{
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initSidesBuffer();
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drawEllipse(memory, x, y, r, r, 0, setElliSide);
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drawEllipse(memory, x - r, y - r, x + r, y + r, 0, setElliSide);
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drawSidesBuffer(memory, y - r, y + r + 1, color);
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}
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void tic_api_circb(tic_mem* memory, s32 x, s32 y, s32 r, u8 color)
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{
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drawEllipse(memory, x, y, r, r, mapColor(memory, color), setElliPixel);
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drawEllipse(memory, x - r, y - r, x + r, y + r, mapColor(memory, color), setElliPixel);
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}
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void tic_api_elli(tic_mem* memory, s32 x, s32 y, s32 a, s32 b, u8 color)
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{
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initSidesBuffer();
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drawEllipse(memory, x , y, a, b, 0, setElliSide);
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drawEllipse(memory, x - a, y - b, x + a, y + b, 0, setElliSide);
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drawSidesBuffer(memory, y - b, y + b + 1, color);
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}
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void tic_api_ellib(tic_mem* memory, s32 x, s32 y, s32 a, s32 b, u8 color)
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{
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drawEllipse(memory, x, y, a, b, mapColor(memory, color), setElliPixel);
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drawEllipse(memory, x - a, y - b, x + a, y + b, mapColor(memory, color), setElliPixel);
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}
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static inline float initLine(float *x0, float *x1, float *y0, float *y1)