--- /dev/null
+; -*- mode: c; tab-width: 4; fill-column: 128 -*-
+; vi: set ts=4 tw=128:
+
+; Texture, Copyright (c) 2017 Dave Odell <dmo2118@gmail.com>
+;
+; Permission to use, copy, modify, distribute, and sell this software and its
+; documentation for any purpose is hereby granted without fee, provided that
+; the above copyright notice appear in all copies and that both that
+; copyright notice and this permission notice appear in supporting
+; documentation. No representations are made about the suitability of this
+; software for any purpose. It is provided "as is" without express or
+; implied warranty.
+
+; A port of 20 year old QBasic code to a much more modern platform.
+
+
+
+
+
+ lda $fe
+ sta src_row
+
+ ldy #0
+top_loop:
+ lda $fe
+ and #$f
+ sbc #$8
+ adc src_row,y
+ iny
+ sta src_row,y
+ cpy #31
+ bne top_loop
+
+lda #$00
+sta $0
+lda #$02
+sta $1
+
+init_loop:
+ jsr tex
+ clc
+ lda $0
+ adc #$20
+ sta $0
+ lda $1
+ adc #0
+ sta $1
+ cmp #$06
+ bne init_loop
+
+lda #$e0
+sta $0
+lda #$05
+sta $1
+
+loop:
+ ;jmp skip_blit
+
+ clc
+ lda #0
+ blit_loop2:
+ tay
+ lda $0220,y
+ sta $0200,y
+ lda $0221,y
+ sta $0201,y
+ lda $0222,y
+ sta $0202,y
+ lda $0223,y
+ sta $0203,y
+ lda $0224,y
+ sta $0204,y
+ lda $0225,y
+ sta $0205,y
+ lda $0226,y
+ sta $0206,y
+ lda $0227,y
+ sta $0207,y
+
+ tya
+ adc #8
+ bne blit_loop2
+
+ clc
+ lda #0
+ blit_loop3:
+ tay
+ lda $0320,y
+ sta $0300,y
+ lda $0321,y
+ sta $0301,y
+ lda $0322,y
+ sta $0302,y
+ lda $0323,y
+ sta $0303,y
+ lda $0324,y
+ sta $0304,y
+ lda $0325,y
+ sta $0305,y
+ lda $0326,y
+ sta $0306,y
+ lda $0327,y
+ sta $0307,y
+
+ tya
+ adc #8
+ bne blit_loop3
+
+ clc
+ lda #0
+ blit_loop4:
+ tay
+ lda $0420,y
+ sta $0400,y
+ lda $0421,y
+ sta $0401,y
+ lda $0422,y
+ sta $0402,y
+ lda $0423,y
+ sta $0403,y
+ lda $0424,y
+ sta $0404,y
+ lda $0425,y
+ sta $0405,y
+ lda $0426,y
+ sta $0406,y
+ lda $0427,y
+ sta $0407,y
+
+ tya
+ adc #8
+ bne blit_loop4
+
+ lda #0
+ blit_loop5:
+ tay
+ lda $0520,y
+ sta $0500,y
+ lda $0521,y
+ sta $0501,y
+ lda $0522,y
+ sta $0502,y
+ lda $0523,y
+ sta $0503,y
+ lda $0524,y
+ sta $0504,y
+ lda $0525,y
+ sta $0505,y
+ lda $0526,y
+ sta $0506,y
+ lda $0527,y
+ sta $0507,y
+
+ tya
+ clc
+ adc #8
+ cmp #$e0
+ bne blit_loop5
+
+ skip_blit:
+
+ jsr tex
+jmp loop
+
+tex:
+ lda $fe
+ and #$f
+ sbc #$8
+ adc src_row
+ sta src_row
+
+ ldy #0
+ tax
+ lda pal0,x
+ sta ($0),y
+ tex_loop0:
+ lda $fe
+ and #$f
+ sbc #$8
+ ;clc
+ adc src_row,y
+ iny
+ ;clc
+ adc src_row,y
+ ror
+ sta src_row,y
+
+ tax
+ lda pal0,x
+ sta ($0),y
+
+ cpy #31
+ bne tex_loop0
+ rts
+
+pal0:
+ dcb $00, $00, $00, $00, $00, $00, $00, $00
+ dcb $00, $00, $0b, $0b, $0b, $0b, $0b, $0b
+ dcb $0b, $0b, $0b, $0b, $0b, $0b, $0b, $0b
+ dcb $0c, $0c, $0c, $0c, $0c, $0c, $0c, $0c
+ dcb $0c, $0c, $0c, $0c, $0c, $0c, $0c, $0c
+ dcb $0f, $0f, $0f, $0f, $0f, $0f, $0f, $0f
+ dcb $0f, $0f, $0f, $0f, $0f, $0f, $0f, $0f
+ dcb $0f, $01, $01, $01, $01, $01, $01, $01
+ dcb $01, $01, $01, $01, $01, $01, $01, $01
+ dcb $0f, $0f, $0f, $0f, $0f, $0f, $0f, $0f
+ dcb $0f, $0f, $0f, $0f, $0f, $0f, $0f, $0f
+ dcb $0f, $0c, $0c, $0c, $0c, $0c, $0c, $0c
+ dcb $0c, $0c, $0c, $0c, $0c, $0c, $0c, $0c
+ dcb $0c, $0b, $0b, $0b, $0b, $0b, $0b, $0b
+ dcb $0b, $0b, $0b, $0b, $0b, $0b, $0b, $00
+ dcb $00, $00, $00, $00, $00, $00, $00, $00
+ dcb $00, $00, $00, $00, $00, $00, $00, $00
+ dcb $00, $00, $00, $00, $00, $00, $00, $00
+ dcb $0b, $0b, $0b, $0b, $0b, $0b, $0b, $0b
+ dcb $0b, $0b, $0b, $0b, $0b, $0b, $0b, $0b
+ dcb $0b, $0b, $0b, $0b, $0b, $0b, $05, $05
+ dcb $05, $05, $05, $05, $05, $05, $05, $05
+ dcb $05, $05, $05, $05, $05, $05, $05, $05
+ dcb $0d, $0d, $0d, $0d, $0d, $0d, $0d, $0d
+ dcb $0d, $0d, $0d, $0d, $0d, $0d, $0d, $0d
+ dcb $0d, $05, $05, $05, $05, $05, $05, $05
+ dcb $05, $05, $05, $05, $05, $05, $05, $05
+ dcb $05, $05, $05, $0b, $0b, $0b, $0b, $0b
+ dcb $0b, $0b, $0b, $0b, $0b, $0b, $0b, $0b
+ dcb $0b, $0b, $0b, $0b, $0b, $0b, $0b, $0b
+ dcb $0b, $00, $00, $00, $00, $00, $00, $00
+ dcb $00, $00, $00, $00, $00, $00, $00, $00
+
+src_row:
+ ; (32 bytes)
+
+; A full-resolution version of the same thing. Not perhaps the most interesting thing to look at.
+
+;#include "screenhack.h"
+;
+;#include <inttypes.h>
+;
+;struct texture
+;{
+; unsigned width, height;
+; Colormap colormap;
+; GC gc;
+; unsigned long palette[128];
+; XImage *image;
+; uint8_t *row;
+; unsigned graininess;
+; unsigned lines;
+;};
+;
+;#define GRAIN(self) (NRAND((self)->graininess * 2 + 1) - (self)->graininess)
+;
+;static void _put_line(struct texture *self, Display *dpy, Window window, unsigned y)
+;{
+; unsigned x;
+; for(x = 0; x != self->width; ++x)
+; {
+; unsigned c1 = self->row[x];
+; unsigned c0 = c1;
+; if(c0 & 64)
+; c0 ^= 127;
+; XPutPixel(self->image, x, 0, self->palette[(c0 & 63) | ((c1 & 0x80) >> 1)]);
+; }
+;
+; XPutImage(dpy, window, self->gc, self->image, 0, 0, 0, y, self->width, 1);
+;
+; *self->row += GRAIN(self);
+;
+; for(x = 1; x != self->width; ++x);
+; {
+; unsigned avg = self->row[x - 1] + self->row[x];
+; self->row[x] = ((avg + ((avg & 2) >> 1)) >> 1) + GRAIN(self);
+; }
+;
+;
+;}
+;
+;static void texture_reshape(Display *dpy, Window window, void *self_raw, unsigned w, unsigned h)
+;{
+; struct texture *self = self_raw;
+; unsigned x, y;
+;
+; if(w == self->width && h == self->height)
+; return;
+;
+; self->image->bytes_per_line = 0;
+; self->image->width = w;
+; XInitImage(self->image);
+;
+; free(self->row);
+; self->row = malloc(w);
+; free(self->image->data);
+; self->image->data = malloc(w * self->image->bytes_per_line);
+;
+; self->width = w;
+; self->height = h;
+;
+; *self->row = NRAND(0xff);
+; for(x = 1; x != self->width; ++x)
+; self->row[x] = self->row[x - 1] + GRAIN(self);
+;
+; for(y = 0; y != self->height; ++y)
+; _put_line(self, dpy, window, y);
+;}
+;
+;static void *texture_init(Display *dpy, Window window)
+;{
+; static const XGCValues gcv_src = {GXcopy};
+; XGCValues gcv = gcv_src;
+; struct texture *self = malloc(sizeof(*self));
+; XWindowAttributes xwa;
+; unsigned i;
+;
+; XGetWindowAttributes(dpy, window, &xwa);
+; self->width = 0;
+; self->height = 0;
+; self->colormap = xwa.colormap;
+;
+; self->graininess = get_integer_resource(dpy, "graininess", "Graininess");
+; self->lines = get_integer_resource(dpy, "speed", "Speed");
+;
+; for(i = 0; i != 64; ++i)
+; {
+; XColor color;
+; unsigned short a = i * (0x10000 / 64);
+;
+; color.red = a;
+; color.green = a;
+; color.blue = a;
+; if(!XAllocColor(dpy, xwa.colormap, &color))
+; abort();
+; self->palette[i] = color.pixel;
+;
+; color.red = 0;
+; color.green = a;
+; color.blue = 0;
+; if(!XAllocColor(dpy, xwa.colormap, &color))
+; abort();
+; self->palette[i | 64] = color.pixel;
+; }
+;
+; self->gc = XCreateGC(dpy, window, GCFunction, &gcv);
+; self->image = XCreateImage(dpy, xwa.visual, xwa.depth, ZPixmap, 0, NULL, 0, 1, 32, 0);
+; self->row = NULL;
+;
+; texture_reshape(dpy, window, self, xwa.width, xwa.height);
+;
+; return self;
+;}
+;
+;static unsigned long texture_draw(Display *dpy, Window window, void *self_raw)
+;{
+; struct texture *self = self_raw;
+; unsigned y;
+; XCopyArea(dpy, window, window, self->gc, 0, self->lines, self->width, self->height - self->lines, 0, 0);
+; for(y = 0; y != self->lines; ++y)
+; _put_line(self, dpy, window, self->height - self->lines + y);
+; return 16667;
+;}
+;
+;static Bool texture_event (Display *dpy, Window window, void *self_raw, XEvent *event)
+;{
+; return False;
+;}
+;
+;static void texture_free(Display *dpy, Window window, void *self_raw)
+;{
+; struct texture *self = self_raw;
+;
+; XFreeGC(dpy, self->gc);
+; XFreeColors(dpy, self->colormap, self->palette, 128, 0);
+; XDestroyImage(self->image);
+; free(self->row);
+; free(self);
+;}
+;
+;static const char *texture_defaults[] =
+;{
+; "*speed: 2",
+; "*graininess: 1",
+; "*fpsSolid: True",
+; "*fpsTop: True",
+; 0
+;};
+;
+;static XrmOptionDescRec texture_options[] =
+;{
+; {"-speed", ".speed", XrmoptionSepArg, 0},
+; {"-graininess", ".graininess", XrmoptionSepArg, 0},
+; {0, 0, 0, 0}
+;};
+;
+;XSCREENSAVER_MODULE("Texture", texture)
projects / xscreensaver / blobdiff