tweak cx16 mandelbrots

compiler/res/prog8lib/c64graphics.p8

@@ -16,7 +16,7 @@ graphics {
 
     sub clear_screen(ubyte pixelcolor, ubyte bgcolor) {
         memset(bitmap_address, 320*200/8, 0)
-        txt.clear_screen(pixelcolor << 4 | bgcolor, 0)
+        txt.fill_screen(pixelcolor << 4 | bgcolor, 0)
     }
 
     sub line(uword @zp x1, ubyte @zp y1, uword @zp x2, ubyte @zp y2) {
@@ -218,7 +218,7 @@ _ormask     .byte 128, 64, 32, 16, 8, 4, 2, 1
 ; note: this can be even faster if we also have a 256 byte x-lookup table, but hey.
 ; see http://codebase64.org/doku.php?id=base:various_techniques_to_calculate_adresses_fast_common_screen_formats_for_pixel_graphics
 ; the y lookup tables encodes this formula:  bitmap_address + 320*(py>>3) + (py & 7)    (y from 0..199)
-; TODO can we use an assembly function for this to calc this?
+; TODO can we use an assembler function for this to calc this at assembly-time?
 _y_lookup_hi
             .byte  $20, $20, $20, $20, $20, $20, $20, $20, $21, $21, $21, $21, $21, $21, $21, $21
             .byte  $22, $22, $22, $22, $22, $22, $22, $22, $23, $23, $23, $23, $23, $23, $23, $23

compiler/res/prog8lib/c64textio.p8

@@ -11,8 +11,16 @@
 
 txt {
 
-asmsub  clear_screen (ubyte char @ A, ubyte charcolor @ Y) clobbers(A)  {
-	; ---- clear the character screen with the given fill character and character color.
+asmsub  clear_screen() {
+    %asm {{
+        lda  #' '
+        jmp  clear_screenchars
+    }}
+}
+
+
+asmsub  fill_screen (ubyte char @ A, ubyte charcolor @ Y) clobbers(A)  {
+	; ---- fill the character screen with the given fill character and character color.
 	;      (assumes screen and color matrix are at their default addresses)
 
 	%asm {{

compiler/res/prog8lib/cx16textio.p8

@@ -11,11 +11,26 @@
 
 txt {
 
-asmsub  clear_screen (ubyte char @ A, ubyte txtcolor @ Y) clobbers(A)  {
+sub  clear_screen() {
+    c64.CHROUT(147)         ; clear screen (spaces)
+}
+
+
+asmsub  fill_screen (ubyte char @ A, ubyte txtcolor @ Y) clobbers(A)  {
 	; ---- clear the character screen with the given fill character and character color.
 
 	%asm {{
-	    brk     ; TODO
+	    pha
+	    tya
+	    and  #$0f
+	    lda  txt.color_to_charcode,y
+	    jsr  c64.CHROUT
+	    pla
+	    cmp  #' '
+	    bne  +
+	    lda  #147       ; clear screen
+	    jmp  c64.CHROUT
++       brk         ; TODO fill screen with another character than space....
         }}
 
 }

examples/cx16/mandelbrot-gfx.p8

@@ -1,22 +1,26 @@
+%import cx16textio
 %import cx16flt
 %zeropage basicsafe
 
 main {
     const uword width = 256
     const uword height = 200
-    const ubyte max_iter = 16
+    const ubyte max_iter = 32
 
     sub start()  {
+        initialize()
+        mandel()
+        repeat {
+            ; do nothing
+        }
+    }
 
-        void cx16.screen_set_mode($80)
-        cx16.r0=0
-        cx16.FB_init()
-
+    sub mandel() {
         ubyte pixelx
         ubyte pixely
 
         for pixely in 0 to height-1 {
-            float yy = (pixely as float)/0.4/height - 1.0
+            float yy = (pixely as float)/0.35/height - 1.35
 
             cx16.r0 = 0
             cx16.r1 = pixely
@@ -40,6 +44,44 @@ main {
                 }
                 cx16.FB_set_pixel(max_iter-iter)
             }
+
+            print_time()
         }
     }
+
+    sub initialize() {
+        void cx16.screen_set_mode($80)
+
+        txt.plot(32, 5)
+        txt.print("256*200")
+        txt.plot(32, 6)
+        txt.print("mandel-")
+        txt.plot(33, 7)
+        txt.print("brot")
+        txt.plot(32, 9)
+        txt.print("floats")
+        txt.plot(32, 10)
+        txt.print("32 iter")
+
+        cx16.r0 = 0
+        cx16.r1 = 0
+        cx16.r2 = 0
+        cx16.r3 = 0
+        cx16.clock_set_date_time()
+
+        cx16.r0=0
+        cx16.FB_init()
+    }
+
+    sub print_time() {
+        cx16.clock_get_date_time()
+        txt.plot(33, 12)
+        if lsb(cx16.r2) < 10
+            c64.CHROUT('0')
+        txt.print_ub(lsb(cx16.r2))
+        c64.CHROUT(':')
+        if msb(cx16.r2) < 10
+            c64.CHROUT('0')
+        txt.print_ub(msb(cx16.r2))
+    }
 }

examples/cx16/mandelbrot.p8

@@ -14,10 +14,10 @@ main {
         ubyte pixely
 
         for pixely in 0 to height-1 {
-            float yy = (pixely as float)/0.4/height - 1.0
+            float yy = (pixely as float)/0.40/height - 1.3
 
             for pixelx in 0 to width-1 {
-                float xx = (pixelx as float)/0.3/width - 2.2
+                float xx = (pixelx as float)/0.32/width - 2.2
 
                 float xsquared = 0.0
                 float ysquared = 0.0

examples/line-circle-txt.p8

@@ -16,13 +16,13 @@ main {
         txt.print("enter for disc:")
         void c64.CHRIN()
         c64.CHROUT('\n')
-        txt.clear_screen(' ', 1)
+        txt.clear_screen()
         disc(20, 12, 12)
 
         txt.print("enter for lines:")
         void c64.CHRIN()
         c64.CHROUT('\n')
-        txt.clear_screen(' ', 1)
+        txt.clear_screen()
 
         line(1, 10, 38, 24)
         line(1, 20, 38, 2)
@@ -32,7 +32,7 @@ main {
         txt.print("enter for rectangles:")
         void c64.CHRIN()
         c64.CHROUT('\n')
-        txt.clear_screen(' ', 1)
+        txt.clear_screen()
 
         rect(4, 8, 37, 23, false)
         rect(20, 12, 30, 20, true)