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Dead code lines everywhere...*sigh*...118 bytes saved

This commit is contained in:
Christian Kroll 2012-05-04 20:46:25 +00:00
parent a2ff6a4142
commit 028dea2b87
1 changed files with 25 additions and 34 deletions
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59
animations/blackhole.c
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@ -10,17 +10,17 @@
/**
* Integer variant of the sinus function which takes an integer based angle
* Integer variant of the sine function which takes an integer based angle
* (range from 0 to 63) where sin_i(64) corresponds to sin(2 * M_PI) * 64 and
* sin_i(16) corresponds to sin(0.5 * M_PI) * 64 (each excluding the fractional
* part). It uses a lookup table which models one quarter of a full sinus period
* sin_i(16) corresponds to sin(M_PI_2) * 64 (each excluding the fractional
* part). It uses a lookup table which models one quarter of a full sine period
* and calculates the rest of the function from that quarter.
* @param angle angle based on an integer (range from 0 to 63)
* @return result of the sinus function normalized to a range from -64 to 64
* @return result of the sine function normalized to a range from -64 to 64
*/
static signed char sin_i(unsigned char angle) {
static signed char sin_i(signed char angle) {
// the aforementioned lookup table
static signed char const sinus_table[] PROGMEM =
static signed char const sine_table[] PROGMEM =
{0, 6, 12, 19, 24, 30, 36, 41, 45, 49, 53, 56, 59, 61, 63, 64};
// determine correct index for the lookup table depending on the given angle
@ -36,17 +36,17 @@ static signed char sin_i(unsigned char angle) {
index = 63 - angle;
}
return (signed char)(PGM(sinus_table[index])) * (angle < 32 ? 1 : -1);
return (signed char)(PGM(sine_table[index])) * (angle < 32 ? 1 : -1);
}
/**
* Integer variant of the cosinus function which takes an integer based angle
* Integer variant of the cosine function which takes an integer based angle
* (range from 0 to 63) where cos_i(64) corresponds to cos(2 * M_PI) * 64 and
* cos_i(16) corresponds to cos(0.5 * M_PI) * 64. It uses the sin_i function and
* shifts the given angle by 16 (which corresponds to 90 degrees).
* cos_i(16) corresponds to cos(M_PI_2) * 64. It uses the sin_i function and
* shifts the given angle by 16 (which corresponds to a delta of 90 degrees).
* @param angle angle based on an integer (range from 0 to 63)
* @return result of the cosinus function normalized to a range from -64 to 64
* @return result of the cosine function normalized to a range from -64 to 64
*/
static signed char cos_i(unsigned char const angle) {
return sin_i(angle + 16);
@ -60,32 +60,22 @@ static signed char cos_i(unsigned char const angle) {
* Draws a black hole like pattern (viewed from different perspectives).
*/
void blackhole(void) {
pixel circlePoints[NUM_CIRCLE][8];
unsigned char add = 0;
signed char firstRadius = 80, helpRadius, angle = 0, x, y;
signed char firstRadius = 80, helpRadius, angle = 0, add = 0;
// initialize data
for (int k = 0; k < 800; k++) {
if (k > 300)
for (unsigned int k = 0; k < 800; k++) {
if (k > 300) {
add = k / 16;
}
helpRadius = firstRadius;
for (unsigned char i = 0; i < NUM_CIRCLE; i++) {
for (unsigned char j = 0; j < 8; j++) {
if (j & 1) {
circlePoints[i][j].x = 64
+ (cos_i(angle + j * 8) * helpRadius) / 64;
circlePoints[i][j].y = 64
+ (sin_i(angle + add + j * 8) * helpRadius) / 64;
} else {
circlePoints[i][j].x = 64 +
(cos_i(angle + j * 8 + 4) * helpRadius) / 64;
circlePoints[i][j].y = 64 +
(sin_i(angle + add + j * 8 + 4) * helpRadius) / 64;
for (signed char i = 0; i < NUM_CIRCLE; i++) {
for (signed char j = 0; j < 64; j += 8) {
signed char a = (j & 0x08) ? 0 : 4;
pixel p;
p.x = (64 + cos_i(angle + j + a) * helpRadius / 64) >> 3;
p.y = (64 + sin_i(angle + add + j + a) * helpRadius / 64) >> 3;
if ((p.x < NUM_COLS) && (p.y < NUM_ROWS)) {
setpixel(p, 3);
}
x = circlePoints[i][j].x / 8;
y = circlePoints[i][j].y / 8;
if (x < 16 && y < 16)
setpixel((pixel){x, y}, 3);
}
helpRadius = (helpRadius * 2) / 3;
}
@ -93,7 +83,8 @@ void blackhole(void) {
clear_screen(0);
angle++;
firstRadius += 2;
if (firstRadius > 119)
if (firstRadius > 119) {
firstRadius = 80;
}
}
}