Switch references from SDL_Rect to vm_area

We still use SDL_Rect internally, but we want to abstract the use of it
in our API. The only thing the rest of the app should care about is the
vm_area struct.

include/vm_bitfont.h

@@ -15,7 +15,7 @@ typedef struct {
     char cmask;
 } vm_bitfont;
 
-extern int vm_bitfont_render(vm_bitfont *, vm_screen *, SDL_Rect *, char);
+extern int vm_bitfont_render(vm_bitfont *, vm_screen *, vm_area *, char);
 extern vm_bitfont *vm_bitfont_create(vm_screen *, const char *, int, int, char);
 extern void vm_bitfont_free(vm_bitfont *);
 extern void vm_bitfont_offset(vm_bitfont *, char, int *, int *);

include/vm_screen.h

@@ -15,15 +15,39 @@
 #define vm_screen_draw_pixel(screen, xpos, ypos) \
     vm_screen_draw_rect(screen, xpos, ypos, 1, 1)
 
+typedef struct {
+    int xoff;
+    int yoff;
+
+    int width;
+    int height;
+} vm_area;
+
 typedef struct {
     SDL_Window *window;
     SDL_Renderer *render;
-    SDL_Rect rect;
+    vm_area area;
 
     int xcoords;
     int ycoords;
 } vm_screen;
 
+#define SET_SDL_RECT(name, a) \
+    (name).x = (a).xoff; \
+    (name).y = (a).yoff; \
+    (name).w = (a).width; \
+    (name).h = (a).height
+
+#define MAKE_SDL_RECT(name, a) \
+    SDL_Rect name; \
+    SET_SDL_RECT(name, a)
+
+#define vm_area_set(a, x, y, w, h) \
+    (a)->xoff = x; \
+    (a)->yoff = y; \
+    (a)->width = w; \
+    (a)->height = h
+
 extern bool vm_screen_active(vm_screen *);
 extern int vm_screen_add_window(vm_screen *, int, int);
 extern int vm_screen_init();

src/apple2.draw.c

@@ -72,7 +72,7 @@ apple2_draw_text(apple2 *mach, vm_16bit addr)
 {
     vm_8bit lsb, msb;
     vm_16bit page_base;
-    SDL_Rect dest;
+    vm_area dest;
     char ch;
 
     // The text display buffers are located at "Page 1" and "Page 2",
@@ -120,18 +120,18 @@ apple2_draw_text(apple2 *mach, vm_16bit addr)
 
     // The absolute column position will be the font width times the
     // lsb.
-    dest.x = lsb * mach->sysfont->width;
+    dest.xoff = lsb * mach->sysfont->width;
 
     // The absolute row position will be the font height times the msb
     // minus the page base (because the height is the same regardless of
     // what page we're in). So if we're msb $0400, then we're starting
     // on pixel row 0; but if we're msb $0480, then we are starting on
     // pixel row 8 (where the font height is 8); etc.
-    dest.y = ((addr & 0xff80) - page_base) * mach->sysfont->height;
+    dest.yoff = ((addr & 0xff80) - page_base) * mach->sysfont->height;
 
     // Our width and height must be that of the font.
-    dest.w = mach->sysfont->width;
-    dest.h = mach->sysfont->height;
+    dest.width = mach->sysfont->width;
+    dest.height = mach->sysfont->height;
 
     // And...lastly...what's in the address?
     ch = (char)vm_segment_get(mach->memory, addr);

src/vm_bitfont.c

@@ -83,10 +83,11 @@ vm_bitfont_offset(vm_bitfont *font, char ch, int *xcoord, int *ycoord)
 int
 vm_bitfont_render(vm_bitfont *font, 
                   vm_screen *screen, 
-                  SDL_Rect *dest, 
+                  vm_area *dest, 
                   char ch)
 {
-    SDL_Rect src;
+    SDL_Rect src_rect;
+    SDL_Rect dest_rect;
 
     // Our bitmap font may not be able to support all 256 possible
     // values that a character can hold; the cmask will limit us to
@@ -95,20 +96,19 @@ vm_bitfont_render(vm_bitfont *font,
 
     // The width and height of the glyph are as indicated by the font
     // struct
-    src.w = font->width;
-    src.h = font->height;
+    src_rect.w = font->width;
+    src_rect.h = font->height;
 
-    // The source and destination width/height must match. This might be
-    // a faulty assumption down the road; for now, it holds.
-    dest->w = src.w;
-    dest->h = src.h;
+    // Bring the destination attributes into the SDL_Rect we need to
+    // pass into SDL_RenderCopy().
+    SET_SDL_RECT(dest_rect, *dest);
 
     // Get the spot in the bitmap where the glyph is found
-    vm_bitfont_offset(font, ch, &src.x, &src.y);
+    vm_bitfont_offset(font, ch, &src_rect.x, &src_rect.y);
 
-    log_critical("src.x = %d, src.y = %d", src.x, src.y);
+    log_critical("src.x = %d, src.y = %d", src_rect.x, src_rect.y);
 
-    if (SDL_RenderCopy(screen->render, font->texture, &src, dest) < 0) {
+    if (SDL_RenderCopy(screen->render, font->texture, &src_rect, &dest_rect) < 0) {
         log_critical("Failed to render glyph: %s", SDL_GetError());
         return ERR_GFXOP;
     }

src/vm_screen.c

@@ -61,10 +61,7 @@ vm_screen_create()
 
     screen->window = NULL;
     screen->render = NULL;
-    screen->rect.x = 0;
-    screen->rect.y = 0;
-    screen->rect.w = 0;
-    screen->rect.h = 0;
+    vm_area_set(&screen->area, 0, 0, 0, 0);
 
     return screen;
 }
@@ -213,12 +210,14 @@ vm_screen_draw_rect(vm_screen *screen,
                     int xsize,
                     int ysize)
 {
+    SDL_Rect rect; 
+
     // The renderer will take care of translating the positions and
     // sizes into whatever the window is really at.
-    screen->rect.x = xpos;
-    screen->rect.y = ypos;
-    screen->rect.w = xsize;
-    screen->rect.h = ysize;
+    rect.x = xpos;
+    rect.y = ypos;
+    rect.w = xsize;
+    rect.h = ysize;
 
-    SDL_RenderFillRect(screen->render, &screen->rect);
+    SDL_RenderFillRect(screen->render, &rect);
 }

tests/vm_screen.c

@@ -33,10 +33,10 @@ Test(vm_screen, create) {
 
     cr_assert_eq(screen->window, NULL);
     cr_assert_eq(screen->render, NULL);
-    cr_assert_eq(screen->rect.x, 0);
-    cr_assert_eq(screen->rect.y, 0);
-    cr_assert_eq(screen->rect.w, 0);
-    cr_assert_eq(screen->rect.h, 0);
+    cr_assert_eq(screen->area.xoff, 0);
+    cr_assert_eq(screen->area.yoff, 0);
+    cr_assert_eq(screen->area.width, 0);
+    cr_assert_eq(screen->area.height, 0);
     cr_assert_eq(screen->xcoords, 0);
     cr_assert_eq(screen->ycoords, 0);
 }