bitmap lines and circles

docs/source/todo.rst

@@ -2,6 +2,9 @@
 TODO
 ====
 
+- fix the invalid assembly generation problem (invalid_assembly.p8)
+
+
 - implement the asm for bitshift on arrays (last missing assembly code generation)
 
 - add a routine to plot a single bitmap pixel

examples/invalid_assembly.p8

@@ -0,0 +1,67 @@
+%import c64lib
+%import c64utils
+%zeropage basicsafe
+
+; TODO WHY DOES THIS GENERATE INVALID ASSEMBLY AT THE A=@(addr) line in Plot() ????
+
+
+main {
+
+    sub start() {
+        circles()
+        lines()
+    }
+
+    sub circles() {
+        ubyte xx
+        for xx in 1 to 5 {
+            circle(50 + xx*40, 50+xx*15, (xx+10)*4, xx)
+            disc(50 + xx*40, 50+xx*15, (xx+10)*2, xx)
+        }
+    }
+
+    sub lines() {
+        uword xx
+        ubyte yy
+        ubyte color
+        ubyte iter
+
+        for iter in 0 to 150 {
+            plot(xx, yy, color)
+        }
+    }
+
+
+    sub circle(uword xcenter, ubyte ycenter, ubyte radius, ubyte color) {
+        ubyte x = radius
+        ubyte y = 0
+        byte decisionOver2 = 1-x
+
+        while x>=y {
+            y++
+        }
+    }
+
+    sub disc(uword cx, ubyte cy, ubyte radius, ubyte color) {
+        ; Midpoint algorithm, filled
+        ubyte x = radius
+        ubyte y = 0
+        byte decisionOver2 = 1-x
+        uword xx
+
+        while x>=y {
+            for xx in cx to cx+x {
+                plot(100, 100, 2)
+            }
+        }
+    }
+
+    sub plot(uword px, ubyte py, ubyte color) {
+        uword addr = 320
+        A=@(addr)           ; TODO invalid assemlby generated    lda (addr),y    something to do with zeropage allocation????
+        @(addr) = A
+    }
+
+}
+
+

examples/lines-circles-gfx.p8

@@ -0,0 +1,131 @@
+%import c64lib
+%import c64utils
+%zeropage basicsafe
+
+
+main {
+
+    const uword bitmap_address = $2000
+
+
+    sub start() {
+
+        ; enable bitmap screen, erase it and set colors to black/white.
+        c64.SCROLY |= %00100000
+        c64.VMCSB = (c64.VMCSB & %11110000) | %00001000   ; $2000-$3fff
+        memset(bitmap_address, 320*200/8, 0)
+        c64scr.clear_screen($10, 0)
+
+        circles()
+        lines()
+    }
+
+
+    ; fast asm plot via lookup tables http://codebase64.org/doku.php?id=base:various_techniques_to_calculate_adresses_fast_common_screen_formats_for_pixel_graphics
+
+    sub circles() {
+        ubyte xx
+        for xx in 1 to 5 {
+            circle(50 + xx*40, 50+xx*15, (xx+10)*4, xx)
+            ; disc(50 + xx*40, 50+xx*15, (xx+10)*2, xx)
+        }
+    }
+
+    sub lines() {
+        uword xx
+        ubyte yy
+        ubyte color
+        ubyte iter
+
+        for color in 0 to 15 {
+            xx = color * 16
+            yy = color + 20
+            for iter in 0 to 150 {
+                plot(xx, yy, color)
+                xx++
+                yy++
+            }
+        }
+    }
+
+
+    sub circle(uword xcenter, ubyte ycenter, ubyte radius, ubyte color) {
+        ; Midpoint algorithm
+        ubyte x = radius
+        ubyte y = 0
+        byte decisionOver2 = 1-x
+
+        while x>=y {
+            plot(xcenter + x, ycenter + y as ubyte, color)
+            plot(xcenter - x, ycenter + y as ubyte, color)
+            plot(xcenter + x, ycenter - y as ubyte, color)
+            plot(xcenter - x, ycenter - y as ubyte, color)
+            plot(xcenter + y, ycenter + x as ubyte, color)
+            plot(xcenter - y, ycenter + x as ubyte, color)
+            plot(xcenter + y, ycenter - x as ubyte, color)
+            plot(xcenter - y, ycenter - x as ubyte, color)
+            y++
+            if decisionOver2<=0
+                decisionOver2 += 2*y+1
+            else {
+                x--
+                decisionOver2 += 2*(y-x)+1
+            }
+        }
+    }
+
+;    sub disc(uword cx, ubyte cy, ubyte radius, ubyte color) {
+;        ; Midpoint algorithm, filled
+;        ubyte x = radius
+;        ubyte y = 0
+;        byte decisionOver2 = 1-x
+;        uword xx
+;
+;        while x>=y {
+;            for xx in cx to cx+x {
+;                plot(xx, cy + y as ubyte, color)
+;                plot(xx, cy - y as ubyte, color)
+;            }
+;            for xx in cx-x to cx-1 {
+;                plot(xx, cy + y as ubyte, color)
+;                plot(xx, cy - y as ubyte, color)
+;            }
+;            for xx in cx to cx+y {
+;                plot(xx, cy + x as ubyte, color)
+;                plot(xx, cy - x as ubyte, color)
+;            }
+;            for xx in cx-y to cx {
+;                plot(xx, cy + x as ubyte, color)
+;                plot(xx, cy - x as ubyte, color)
+;            }
+;            y++
+;            if decisionOver2<=0
+;                decisionOver2 += 2*y+1
+;            else {
+;                x--
+;                decisionOver2 += 2*(y-x)+1
+;            }
+;        }
+;    }
+
+    ; uword[200] yoffsets_lo = $00        ; TODO fix compiler crash about init value type
+
+    sub plot(uword px, ubyte py, ubyte color) {
+        ubyte[] ormask = [128, 64, 32, 16, 8, 4, 2, 1]
+        uword addr = bitmap_address + 320*(py>>3) + (py & 7) + (px & %0000001111111000)
+
+        ; @(addr) |= 128      ; TODO FIX memory-OR/XOR and probably AND as well
+        ; @(addr) += 1      ; TODO fix += 1
+
+        A=@(addr)
+        @(addr) = A | ormask[lsb(px) & 7]
+        ubyte sx = px >> 3
+        ubyte sy = py >> 3
+        c64.SCRATCH_ZPB1 = color << 4
+        c64scr.setchr(sx, sy)
+
+    }
+
+}
+
+

examples/test.p8

@@ -1,46 +1,26 @@
+%import c64lib
 %import c64utils
-;%import c64flt
-;%option enable_floats
-%zeropage dontuse
+%zeropage basicsafe
+
 
 main {
+    uword[2] array1 = 1        ; TODO fix compiler crash about init value type
+
 
     sub start() {
-        byte v1
-        byte v2
+        uword addr = $c000
+        &uword addr2 = $c100
 
-        bla()
-        exit(4)
-        v1 = 100
-        goto start          ; TODO unreachable code warning
-        v2 = 127
-        A=5
-        return
-
-        sub bla () {
-            A=99
-            bla2()
-            exit(99)
-
-            sub bla2 () {
-                A=100
-                return
-                foo.ding()
-                foo.ding2()
-            }
-
-        }
+        ; not sure if these are okay:
+        addr2 =  0
+        addr2 |= 128
+        addr2 += 1
 
+        @(addr) = 0
+        @(addr) |= 128      ; TODO FIX result of memory-OR/XOR and probably AND as well
+        @(addr) += 1      ; TODO fix result of memory += 1
 
     }
 }
 
-foo {
-    ubyte derp=99
-    sub ding() {
-        A=derp
-    }
-    sub ding2() {
-        A=derp
-    }
-}
+