lab5

Lab5/milli.c

+// Simple little unit for timing using the gettimeofday() call.
+// By Ingemar 2009
+
+#include <stdlib.h>
+#include <sys/time.h>
+#include "milli.h"
+
+static struct timeval timeStart;
+static char hasStart = 0;
+
+int GetMilliseconds()
+{
+	struct timeval tv;
+	
+	gettimeofday(&tv, NULL);
+	if (!hasStart)
+	{
+		hasStart = 1;
+		timeStart = tv;
+	}
+	return (tv.tv_usec - timeStart.tv_usec) / 1000 + (tv.tv_sec - timeStart.tv_sec)*1000;
+}
+
+int GetMicroseconds()
+{
+	struct timeval tv;
+	
+	gettimeofday(&tv, NULL);
+	if (!hasStart)
+	{
+		hasStart = 1;
+		timeStart = tv;
+	}
+	return (tv.tv_usec - timeStart.tv_usec) + (tv.tv_sec - timeStart.tv_sec)*1000000;
+}
+
+double GetSeconds()
+{
+	struct timeval tv;
+	
+	gettimeofday(&tv, NULL);
+	if (!hasStart)
+	{
+		hasStart = 1;
+		timeStart = tv;
+	}
+	return (double)(tv.tv_usec - timeStart.tv_usec) / 1000000.0 + (double)(tv.tv_sec - timeStart.tv_sec);
+}
+
+// If you want to start from right now.
+void ResetMilli()
+{
+	struct timeval tv;
+	
+	gettimeofday(&tv, NULL);
+	hasStart = 1;
+	timeStart = tv;
+}
+
+// If you want to start from a specific time.
+void SetMilli(int seconds, int microseconds)
+{
+	hasStart = 1;
+	timeStart.tv_sec = seconds;
+	timeStart.tv_usec = microseconds;
+}

Lab5/milli.h

+#ifndef _MILLI_
+#define _MILLI_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int GetMilliseconds();
+int GetMicroseconds();
+double GetSeconds();
+
+// Optional setting of the start time. If these are not used,
+// the first call to the above functions will be the start time.
+void ResetMilli();
+void SetMilli(int seconds, int microseconds);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

Lab5/readppm.c

+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifdef __APPLE__
+	#include <GLUT/glut.h>
+#else
+	#include <GL/glut.h>
+#endif
+#include "readppm.h"
+
+// By Ingemar Ragnemalm
+// based on a ppm reader by Edward Angel,
+// Added support for binary PPM (2002?)
+// 2006: Fixed a bug that caused some files to end prematurely
+// and added a PPM writer
+// for making screen shots and other output (i.e. GPGPU uses)
+// Added writeppm. (Writes in ASCII format only.)
+// 2009: Added readppmtexture. (A writer for a texture would also be possible when needed.)
+// Portable #include.
+// 2010: Fixed a stupid bug that made non-square textures fail.
+// Still crashes on non-power-of-two.
+// 2010, march: Even more bug fixes, and now it is OK (for power of two).
+// Checks for power of two to avoid crashes.
+// 2010-03-15 A fix in writeppm
+
+int writeppm(char *filename, int width, int height, unsigned char *data)
+{
+	FILE *fp;
+	int error = 1;
+	int i, h, v;
+
+	if (filename != NULL)
+	{
+		fp = fopen(filename,"w");
+		
+		if (fp != NULL)
+		{
+			// Write PPM file
+			// Header	
+			fprintf(fp, "P3\n");
+			fprintf(fp, "# written by Ingemars PPM writer\n");
+			fprintf(fp, "%d %d\n", width, height);
+			fprintf(fp, "%d\n", 255); // range
+			
+			// Data
+			for (v = height-1; v >=0; v--)
+			{
+				for (h = 0; h < width; h++)
+				{
+					i = (width*v + h)*3; // assumes rgb, not rgba
+					fprintf(fp, "%d %d %d ", data[i], data[i+1], data[i+2]);
+				}
+				fprintf(fp, "\n"); // range
+			}
+			
+			if (fwrite("\n",sizeof(char),1,fp) == 1)
+				error = 0; // Probable success
+			fclose(fp);
+		}
+	}
+	return(error);
+}
+
+
+
+unsigned char *readppm(char *filename, int *width, int *height)
+{
+	FILE *fd;
+	int  k;
+	char c;
+	int i,j;
+	char b[100];
+	int red, green, blue;
+	long numbytes;
+	int n;
+	int m;
+	unsigned char *image;
+	
+	fd = fopen(filename, "rb");
+	if (fd == NULL)
+	{
+		printf("Could not open %s\n", filename);
+		return NULL;
+	}
+	c = getc(fd);
+	if (c=='P' || c=='p')
+		c = getc(fd);
+	
+	if (c == '3')
+	{
+		printf("%s is a PPM file (plain text version)\n", filename);
+		
+		// NOTE: This is not very good PPM code! Comments are not allowed
+		// except immediately after the magic number.
+		c = getc(fd);
+		if (c == '\n' || c == '\r') // Skip any line break and comments
+		{
+			c = getc(fd);
+			while(c == '#') 
+			{
+				fscanf(fd, "%[^\n\r] ", b);
+				printf("%s\n",b);
+				c = getc(fd);
+			}
+			ungetc(c,fd); 
+		}
+		fscanf(fd, "%d %d %d", &n, &m, &k);
+		
+		printf("%d rows  %d columns  max value= %d\n",n,m,k);
+		
+		numbytes = n * m * 3;
+		image = (unsigned char *) malloc(numbytes);
+		if (image == NULL)
+		{
+			printf("Memory allocation failed!\n"); 
+			return NULL;
+		}
+		for(i=m-1;i>=0;i--) for(j=0;j<n;j++) // Important bug fix here!
+		{ // i = row, j = column
+			fscanf(fd,"%d %d %d",&red, &green, &blue );
+			image[(i*n+j)*3]=red * 255 / k;
+			image[(i*n+j)*3+1]=green * 255 / k;
+			image[(i*n+j)*3+2]=blue * 255 / k;
+		}
+	}
+	else
+	if (c == '6')
+	{
+		printf("%s is a PPM file (raw version)!\n", filename); 
+		
+		c = getc(fd);
+		if (c == '\n' || c == '\r') // Skip any line break and comments
+		{
+			c = getc(fd);
+			while(c == '#') 
+			{
+				fscanf(fd, "%[^\n\r] ", b);
+				printf("%s\n",b);
+				c = getc(fd);
+			}
+			ungetc(c,fd); 
+		}
+		fscanf(fd, "%d %d %d", &n, &m, &k);
+		printf("%d rows  %d columns  max value= %d\n",m,n,k);
+		c = getc(fd); // Skip the last whitespace
+		
+		numbytes = n * m * 3;
+		image = (unsigned char *) malloc(numbytes);
+		if (image == NULL)
+		{
+			printf("Memory allocation failed!\n"); 
+			return NULL;
+		}
+		// Read and re-order as necessary
+		for(i=m-1;i>=0;i--) for(j=0;j<n;j++) // Important bug fix here!
+		{
+			image[(i*n+j)*3+0]=getc(fd);
+			image[(i*n+j)*3+1]=getc(fd);
+			image[(i*n+j)*3+2]=getc(fd);
+		}
+	}
+	else
+	{
+		printf("%s is not a PPM file!\n", filename); 
+		return NULL;
+	}
+	
+	printf("read image\n");
+	
+	*height = m;
+	*width = n;
+	return image;
+}
+
+// Convenient high-level call
+GLint readppmtexture(char *filename, char dofilter, char dorepeat)
+{
+	int width, height, w, h;
+	unsigned char *image;
+	GLuint tex;
+	
+	image = readppm(filename, &width, &height);
+	
+	// Check if power of 2
+	w = 1;
+	while (w < width) w = w << 1;
+	h = 1;
+	while (h < height) h = h << 1;
+	if ((w > width) || (h > height))
+	{
+		printf("readppmtexture(): Only power of two texture size allowed.\n");
+		printf("Try readppm() with mipmapping instead.\n");
+		return 0;
+	}
+	
+	glGenTextures(1, &tex);
+	glBindTexture(GL_TEXTURE_2D, tex);
+	glPixelStorei(GL_UNPACK_ALIGNMENT,1);
+	glEnable(GL_TEXTURE_2D);
+	glTexImage2D(GL_TEXTURE_2D,0,3,width,height,0,GL_RGB,GL_UNSIGNED_BYTE, image);
+	if (dorepeat)
+	{
+		glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);
+		glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);
+	}
+	else
+	{
+		glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_CLAMP);
+		glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_CLAMP);
+	}
+	if (dofilter)
+	{
+		glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
+		glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
+	}
+	else
+	{
+		glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_NEAREST);
+		glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_NEAREST);
+	}
+	// free(image);
+	
+	return tex;
+}

Lab5/readppm.h

+#ifndef READ_PPM
+#define READ_PPM
+
+#ifdef __APPLE__
+	#include <OpenGL/gl.h>
+#else
+	#include <GL/gl.h>
+#endif
+
+int writeppm(char *filename, int width, int height, unsigned char *data);
+unsigned char *readppm(char *filename, int *width, int *height);
+GLint readppmtexture(char *filename, char dofilter, char dorepeat);
+
+#endif