diff options
| -rw-r--r-- | src/modules/julia/julia.c | 42 |
1 files changed, 28 insertions, 14 deletions
diff --git a/src/modules/julia/julia.c b/src/modules/julia/julia.c index ed8e30c..69d1022 100644 --- a/src/modules/julia/julia.c +++ b/src/modules/julia/julia.c @@ -11,6 +11,12 @@ /* TODO: explore using C99 complex.h and its types? */ +static float rr; +static float realscale; +static float imagscale; +static float creal; +static float cimag; + static inline unsigned julia_iter(float real, float imag, float creal, float cimag, unsigned max_iters) { unsigned i; @@ -34,6 +40,24 @@ static inline unsigned julia_iter(float real, float imag, float creal, float cim return 0; } + +/* Prepare a frame for concurrent drawing of fragment using multiple fragments */ +static void julia_prepare_frame(unsigned n_cpus, fb_fragment_t *fragment, rototiller_frame_t *res_frame) +{ + res_frame->n_fragments = n_cpus; + fb_fragment_divide(fragment, n_cpus, res_frame->fragments); + + rr += .01; + /* Rather than just sweeping creal,cimag from -2.0-+2.0, I try to keep things confined + * to an interesting (visually) range. TODO: could certainly use refinement. + */ + realscale = 0.01f * cosf(rr) + 0.01f; + imagscale = 0.01f * sinf(rr * 3.0f) + 0.01f; + creal = (1.01f + (realscale * cosf(1.5f*M_PI+rr) + realscale)) * cosf(rr * .3f); + cimag = (1.01f + (imagscale * sinf(rr * 3.0f) + imagscale)) * sinf(rr); +} + + /* Draw a morphing Julia set */ static void julia_render_fragment(fb_fragment_t *fragment) { @@ -78,9 +102,7 @@ static void julia_render_fragment(fb_fragment_t *fragment) 0xaa00aa, 0x880088, 0x440044, - }; - static float rr; unsigned x, y; unsigned stride = fragment->stride / 4, width = fragment->width, height = fragment->height; @@ -88,30 +110,22 @@ static void julia_render_fragment(fb_fragment_t *fragment) float real, imag; float realstep = 3.6f / (float)fragment->frame_width, imagstep = 3.6f / (float)fragment->frame_height; - /* Rather than just sweeping creal,cimag from -2.0-+2.0, I try to keep things confined - * to an interesting (visually) range. TODO: could certainly use refinement. - */ - float realscale = 0.01f * cosf(rr) + 0.01f; - float imagscale = 0.01f * sinf(rr * 3.0f) + 0.01f; - float creal = (1.01f + (realscale * cosf(1.5f*M_PI+rr) + realscale)) * cosf(rr * .3f); - float cimag = (1.01f + (imagscale * sinf(rr * 3.0f) + imagscale)) * sinf(rr); /* Complex plane confined to {-1.8 - 1.8} on both axis (slightly zoomed), no dynamic zooming is performed. */ - for (imag = 1.8, y = 0; y < height; y++, imag += -imagstep) { - for (real = -1.8, x = 0; x < width; x++, buf++, real += realstep) { + for (imag = 1.8 + -(imagstep * (float)fragment->y), y = fragment->y; y < fragment->y + height; y++, imag += -imagstep) { + for (real = -1.8 + realstep * (float)fragment->x, x = fragment->x; x < fragment->x + width; x++, buf++, real += realstep) { *buf = colors[julia_iter(real, imag, creal, cimag, sizeof(colors) / sizeof(*colors))]; } buf += stride; } - - rr += .01; } rototiller_module_t julia_module = { + .prepare_frame = julia_prepare_frame, .render_fragment = julia_render_fragment, .name = "julia", - .description = "Julia set fractal morpher", + .description = "Julia set fractal morpher (threaded)", .author = "Vito Caputo <vcaputo@pengaru.com>", .license = "GPLv2", }; |