Major changes. Optional XShm support, bilinear scaling, caching WIP

1 files changed, 130 insertions, 52 deletions

diff --git a/src/xlib.c b/src/xlib.c
index d36a931..511e740 100644
--- a/src/xlib.c
+++ b/src/xlib.c
@@ -7,6 +7,9 @@
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
 #include <X11/keysym.h>
+#include <X11/extensions/XShm.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
 
 #include "meh.h"
 
@@ -16,80 +19,139 @@ int screen;
 Window window;
 GC gc;
 
-static unsigned int getshift(unsigned int mask){
-#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)
-	return __builtin_ctz(mask);
-#else
-	int i = 0;
-	while((mask & 1) == 0){
-		i++;
-		mask >>= 1;
+int xshm = 0;
+
+#define GETVAL(x, c) (ibuf[(x) * 3 + (c)])
+#define GETLVAL(x, y, u, v, c) (( \
+			(GETVAL((x), (c)) * (1023^(u)) + GETVAL((x)+1, (c)) * (u)) * (1023^(v)) + \
+			(GETVAL((x)+img->bufwidth, (c)) * (1023^(u)) + GETVAL((x)+img->bufwidth+1, (c)) * (u)) * (v)) >> 20)
+
+void scale(struct image *img, XImage *ximg){
+	int x, y;
+	unsigned char * __restrict__ ibuf;
+	char* __restrict__ newBuf = ximg->data;
+	unsigned int jdy = ximg->bytes_per_line / 4 - ximg->width;
+	unsigned int dx = (img->bufwidth << 10) / ximg->width;
+
+	struct timeval t0;
+	struct timeval t1;
+	gettimeofday(&t0, NULL);
+
+	for(y = 0; y < ximg->height; y++){
+		unsigned int bufy = (y << 10) * img->bufheight / ximg->height;
+		unsigned int v_ratio = (bufy & 1023);
+		unsigned int bufx = img->bufwidth / ximg->width;
+		unsigned char *ibuf = &img->buf[y * img->bufheight / ximg->height * img->bufwidth * 3];
+		for(x = ximg->width; x; x--){
+			unsigned int u_ratio = (bufx & 1023);
+
+			*newBuf++ = GETLVAL(bufx >> 10, bufy >> 10, u_ratio, v_ratio, 2);
+			*newBuf++ = GETLVAL(bufx >> 10, bufy >> 10, u_ratio, v_ratio, 1);
+			*newBuf++ = GETLVAL(bufx >> 10, bufy >> 10, u_ratio, v_ratio, 0);
+			newBuf++;
+			
+			bufx += dx;
+		}
+		newBuf += jdy;
 	}
-	return i;
-#endif
+
+	gettimeofday(&t1, NULL);
+	printf("%i ms\n", ((t1.tv_sec - t0.tv_sec) * 1000000 + t1.tv_usec - t0.tv_usec) / 1000);
 }
 
+
+void linearscale(struct image *img, XImage *ximg){
+	unsigned int i;
+	int x, y;
+	unsigned int dx;
+	unsigned char * __restrict__ ibuf;
+	char* __restrict__ newBuf = ximg->data;
+	unsigned int jdy = ximg->bytes_per_line / 4 - ximg->width;
+	dx = (img->bufwidth << 10) / ximg->width;
+
+	struct timeval t0;
+	struct timeval t1;
+	gettimeofday(&t0, NULL);
+
+	for(y = 0; y < ximg->height; y++){
+		i = 0;
+		ibuf = &img->buf[y * img->bufheight / ximg->height * img->bufwidth * 3];
+		for(x = 0; x < ximg->width; x++){
+			*newBuf++ = (ibuf[(i >> 10)*3+2]);
+			*newBuf++ = (ibuf[(i >> 10)*3+1]);
+			*newBuf++ = (ibuf[(i >> 10)*3]);
+			newBuf++;
+			
+			i += dx;
+		}
+		newBuf += jdy;
+	}
+
+	gettimeofday(&t1, NULL);
+	printf("%i ms\n", ((t1.tv_sec - t0.tv_sec) * 1000000 + t1.tv_usec - t0.tv_usec) / 1000);
+}
+
+XShmSegmentInfo *shminfo;
 XImage *ximage(struct image *img, unsigned int width, unsigned int height) {
 	int depth;
 	XImage *ximg = NULL;
 	Visual *vis;
-	unsigned int rshift, gshift, bshift;
-	unsigned int i;
-	unsigned int x,y;
-	unsigned int j = 0;
 
 	depth = DefaultDepth(display, screen);
 	vis = DefaultVisual(display, screen);
 
-	rshift = getshift(vis->red_mask);
-	gshift = getshift(vis->green_mask);
-	bshift = getshift(vis->blue_mask);
-
-	if (depth >= 24) {
-		unsigned char *ibuf;
-		unsigned int dx;
-		size_t numNewBufBytes = ((sizeof(u_int32_t)) * (width) * (height));
-		u_int32_t *newBuf = malloc(numNewBufBytes);
-	
-		dx = 1024 * img->width / width;
-		for(y = 0; y < height; y++){
-			i = 0;
-			ibuf = &img->buf[y * img->height / height * img->width * 3];
-			for(x = 0; x < width; x++){
-				unsigned int r, g, b;
-				r = (ibuf[(i >> 10)*3] << rshift) & vis->red_mask;
-				g = (ibuf[(i >> 10)*3+1] << gshift) & vis->green_mask;
-				b = (ibuf[(i >> 10)*3+2] << bshift) & vis->blue_mask;
-				
-				newBuf[j++] = r | g | b;
-				i += dx;
+	if(depth >= 24){
+		if(xshm){
+			shminfo = malloc(sizeof(XShmSegmentInfo));
+			if(!(ximg = XShmCreateImage(display,
+				CopyFromParent, depth,
+				ZPixmap,
+				NULL,
+				shminfo,
+				width, height
+			))){
+			}
+			if((shminfo->shmid = shmget(IPC_PRIVATE, ximg->bytes_per_line * ximg->height, IPC_CREAT|0777)) == -1){
+				fprintf(stderr, "XShm problems\n");
+				exit(1);
+			}
+			if((shminfo->shmaddr = ximg->data = shmat(shminfo->shmid, 0, 0)) == (void *)-1){
+				fprintf(stderr, "XShm problems\n");
+				exit(1);
+			}
+			shminfo->readOnly = False;
+			if(!XShmAttach(display, shminfo)){
+				fprintf(stderr, "XShm problems, falling back to to XImage\n");
+				xshm = 0;
 			}
 		}
-
-		ximg = XCreateImage (display, 
-			CopyFromParent, depth, 
-			ZPixmap, 0, 
-			(char *) newBuf,
-			width, height,
-			32, 0
-		);
+		if(!xshm){
+			ximg = XCreateImage(display, 
+				CopyFromParent, depth, 
+				ZPixmap, 0, 
+				NULL,
+				width, height,
+				32, 0
+			);
+			ximg->data  = malloc(ximg->bytes_per_line * ximg->height + /*HACK*/(ximg->bytes_per_line+1));
+			XInitImage(ximg);
+		}
+		scale(img, ximg);
 	}else{
 		/* TODO other depths */
-		fprintf(stderr, "This program does not support display depths less than 24.\n");
+		fprintf(stderr, "This program does not yet support display depths <24.\n");
 		exit(1);
 		return NULL;				
 	}
 
-	XInitImage(ximg);
-
 	return ximg;
 }
 
 XImage *getimage(struct image *img, unsigned int width, unsigned int height){
-	if(width * img->height > height * img->width){
-		return ximage(img, img->width * height / img->height, height);
+	if(width * img->bufheight > height * img->bufwidth){
+		return ximage(img, img->bufwidth * height / img->bufheight, height);
 	}else{
-		return ximage(img, width, img->height * width / img->width);
+		return ximage(img, width, img->bufheight * width / img->bufwidth);
 	}
 }
 
@@ -103,7 +165,7 @@ void drawimage(XImage *ximg, unsigned int width, unsigned int height){
 		if(xoffset){
 			rects[0].width = rects[1].width = xoffset;
 			rects[0].height = rects[1].height = height;
-			rects[1].x = width-xoffset;
+			rects[1].x = width - xoffset;
 			rects[1].y = 0;
 		}else if(yoffset){
 			rects[0].width = rects[1].width = width;
@@ -113,10 +175,26 @@ void drawimage(XImage *ximg, unsigned int width, unsigned int height){
 		}
 		XFillRectangles(display, window, gc, rects, 2);
 	}
-	XPutImage(display, window, gc, ximg, 0, 0, xoffset, yoffset, ximg->width, ximg->height);
+	if(xshm){
+		XShmPutImage(display, window, gc, ximg, 0, 0, xoffset, yoffset, ximg->width, ximg->height, False);
+	}else{
+		XPutImage(display, window, gc, ximg, 0, 0, xoffset, yoffset, ximg->width, ximg->height);
+	}
 	XFlush(display);
 }
 
+void freeXImg(XImage *ximg){
+	if(xshm){
+		XShmDetach(display, shminfo);
+		XDestroyImage(ximg);
+		shmdt(shminfo->shmaddr);
+		shmctl(shminfo->shmid, IPC_RMID, 0);
+		free(shminfo);
+	}else{
+		XDestroyImage(ximg);
+	}
+}
+
 
 void setaspect(unsigned int w, unsigned int h){
 	XSizeHints *hints = XAllocSizeHints();