lec11

CallbyAddressAndCallbyValue.c

+#include <stdio.h>
+
+void addPointer(int *a, int *b, int *c)
+{
+	*c =  *a + *b;
+	fprintf(stdout, "In addPointer A %d : %lld %llx\n", *a, a, a); 
+	fprintf(stdout, "In addPointer B %d : %lld %llx\n", *b, b, b); 
+	fprintf(stdout, "In addPointer C %d : %lld %llx\n", *c, c, c); 
+	*a = -100;
+	*b = -200; 
+}
+
+int addValue(int a, int b, int c)
+{
+	c =  a + b;
+	fprintf(stdout, "In addValue A %d : %lld %llx\n", a, &a, &a); 
+	fprintf(stdout, "In addValue B %d : %lld %llx\n", b, &b, &b); 
+	fprintf(stdout, "In addValue C %d : %lld %llx\n", c, &c, &c); 
+	a = 999; b=888;
+	return c; 
+}
+
+int main()
+{
+	int a = 100;
+	int b = 200;
+	int c = 999;
+
+	fprintf(stdout, "%d : %lld %llx\n", a, &a, &a); 
+	fprintf(stdout, "%d : %lld %llx\n", b, &b, &b); 
+	addPointer(&a,&b,&c); 
+	fprintf(stdout, "%d : %lld %llx\n", c, &c, &c); 
+	// a = 200; b = 300; 
+	c = addValue(a,b,c); 
+	fprintf(stdout, "%d : %lld %llx\n", a, &a, &a); 
+	fprintf(stdout, "%d : %lld %llx\n", b, &b, &b); 
+	fprintf(stdout, "%d : %lld %llx\n", c, &c, &c); 
+}
+

lec10/test3.c

+#include <stdio.h>
+
+int fxMul1(int a, int b)
+{
+	return a*b; 
+}
+
+int fxMul2(int a, int b)
+{
+	return (int)((long long) a * (long long) b) ; 
+}
+
+int main()
+{
+	int i=0; 
+	int ia, ib, ic, ic2; 
+	float fa; 
+	// fscanf(stdin, "%d %d", &ia, &ib); 
+	for ( i = 0; i < 64*256*256*256; i+=(5))
+	{
+		ic = fxMul1(i, i); 
+		ic = fxMul2(i, i); 
+	}
+}

lec11/rgba.c

+#include <stdio.h>
+
+typedef unsigned int t_rgba;
+#define fromRGBA(r,g,b,a) ((((r)&0xff)<<24)|(((g)&0xff)<<16)|(((b)&0xff)<<8)|((a)&0xff)); 
+
+#define F_NUM_1_255	(1.0f/255.0f)
+t_rgba mul_float(t_rgba c1, t_rgba c2)
+{
+	float  r1,g1,b1,a1;
+	float  r2,g2,b2,a2;
+	int    ir,ig,ib,ia;
+	r1 = (float) ((c1 >> 24)       ) * F_NUM_1_255;
+	g1 = (float) ((c1 >> 16) & 0xff) * F_NUM_1_255;
+	b1 = (float) ((c1 >>  8) & 0xff) * F_NUM_1_255;
+	a1 = (float) ((c1      ) & 0xff) * F_NUM_1_255;
+
+	r2 = (float) ((c2 >> 24)       ) * F_NUM_1_255;
+	g2 = (float) ((c2 >> 16) & 0xff) * F_NUM_1_255;
+	b2 = (float) ((c2 >>  8) & 0xff) * F_NUM_1_255;
+	a2 = (float) ((c2      ) & 0xff) * F_NUM_1_255;
+
+	ir = (int) ((r1 * r2) * 255.0f);
+	ig = (int) ((g1 * g2) * 255.0f);
+	ib = (int) ((b1 * b2) * 255.0f);
+	ia = (int) ((a1 * a2) * 255.0f);
+
+	return fromRGBA(ir,ig,ib,ia);
+}
+
+t_rgba mul_int(t_rgba c1, t_rgba c2)
+{
+	unsigned int r1,g1,b1,a1;
+	unsigned int r2,g2,b2,a2;
+	int r,g,b,a;
+	r1 = c1 >> 24		; r2 = c2 >> 24;
+	g1 = (c1 >> 16) & 0xff	; g2 = (c2 >> 16) & 0xff;
+	b1 = (c1 >>  8) & 0xff	; b2 = (c2 >>  8) & 0xff;
+	a1 = c1 & 0xff		; a2 = c2 & 0xff;
+	r = (r1*r2) >> 8;
+	g = (g1*g2) >> 8;
+	b = (b1*b2) >> 8;
+	a = (a1*a2) >> 8;
+	return fromRGBA(r,g,b,a);
+}
+
+//unsigned int fromRGBA(int r, int g, int b, int a)
+//{
+	// return r*256*256*256 + g*256*256 + b*256 + a;
+	//return ((r<<24) + (g<<16) + (b<<8) + a); 
+//	return (((r&0xff)<<24) | ((g&0xff)<<16) | ((b&0xff)<<8) | (a&0xff)); 
+//}
+
+int main()
+{
+	int red, green, blue, alpha;
+	t_rgba rgba_1, rgba_2;
+	// input value must be in 0~255 : 0.0 ~ 1.0 으로 해석 
+	// rgba_1 [rrrrrrrr][gggggggg][bbbbbbbb][aaaaaaaa]
+	printf("Input 4 values with 0~255 ");
+	scanf("%d %d %d %d", &red, &green, &blue, &alpha);
+	rgba_1 = fromRGBA(red, green, blue, alpha);
+	printf("%d %d %d %d : %u 0x%8x\n", red,green,blue,alpha,rgba_1,rgba_1);
+	rgba_2 = mul_float(rgba_1, rgba_1);
+	printf("%d %d %d %d : %u 0x%8x\n", red,green,blue,alpha,rgba_2,rgba_2);
+}