add optional overscan compensation to recovery graphics

If your screen is a TV, it may not actually be displaying the edges of
the framebuffer.  Allow specifying an overscan percentage, and move
each edge of the framebuffer in by that percent of the width/height.
(The gr_* layer just lies to the caller about the size of the
framebuffer, telling the caller it's smaller than it really is, and
offsets all drawing commands to match.)

Change-Id: I11bb2feb39ae522bd3e957a14ebdecf3609e0fdc

minui/Android.mk

@@ -20,4 +20,10 @@ ifeq ($(subst ",,$(TARGET_RECOVERY_PIXEL_FORMAT)),BGRA_8888)
   LOCAL_CFLAGS += -DRECOVERY_BGRA
 endif
 
+ifneq ($(TARGET_RECOVERY_OVERSCAN_PERCENT),)
+  LOCAL_CFLAGS += -DOVERSCAN_PERCENT=$(TARGET_RECOVERY_OVERSCAN_PERCENT)
+else
+  LOCAL_CFLAGS += -DOVERSCAN_PERCENT=0
+endif
+
 include $(BUILD_STATIC_LIBRARY)

minui/graphics.c

@@ -60,6 +60,9 @@ static GGLSurface gr_framebuffer[NUM_BUFFERS];
 static GGLSurface gr_mem_surface;
 static unsigned gr_active_fb = 0;
 static unsigned double_buffering = 0;
+static int overscan_percent = OVERSCAN_PERCENT;
+static int overscan_offset_x = 0;
+static int overscan_offset_y = 0;
 
 static int gr_fb_fd = -1;
 static int gr_vt_fd = -1;
@@ -132,6 +135,9 @@ static int get_framebuffer(GGLSurface *fb)
         return -1;
     }
 
+    overscan_offset_x = vi.xres * overscan_percent / 100;
+    overscan_offset_y = vi.yres * overscan_percent / 100;
+
     fb->version = sizeof(*fb);
     fb->width = vi.xres;
     fb->height = vi.yres;
@@ -224,6 +230,9 @@ int gr_text(int x, int y, const char *s)
     GRFont *font = gr_font;
     unsigned off;
 
+    x += overscan_offset_x;
+    y += overscan_offset_y;
+
     y -= font->ascent;
 
     gl->bindTexture(gl, &font->texture);
@@ -250,6 +259,9 @@ void gr_texticon(int x, int y, gr_surface icon) {
     }
     GGLContext* gl = gr_context;
 
+    x += overscan_offset_x;
+    y += overscan_offset_y;
+
     gl->bindTexture(gl, (GGLSurface*) icon);
     gl->texEnvi(gl, GGL_TEXTURE_ENV, GGL_TEXTURE_ENV_MODE, GGL_REPLACE);
     gl->texGeni(gl, GGL_S, GGL_TEXTURE_GEN_MODE, GGL_ONE_TO_ONE);
@@ -263,11 +275,17 @@ void gr_texticon(int x, int y, gr_surface icon) {
     gl->recti(gl, x, y, x+gr_get_width(icon), y+gr_get_height(icon));
 }
 
-void gr_fill(int x, int y, int w, int h)
+void gr_fill(int x1, int y1, int x2, int y2)
 {
+    x1 += overscan_offset_x;
+    y1 += overscan_offset_y;
+
+    x2 += overscan_offset_x;
+    y2 += overscan_offset_y;
+
     GGLContext *gl = gr_context;
     gl->disable(gl, GGL_TEXTURE_2D);
-    gl->recti(gl, x, y, w, h);
+    gl->recti(gl, x1, y1, x2, y2);
 }
 
 void gr_blit(gr_surface source, int sx, int sy, int w, int h, int dx, int dy) {
@@ -276,6 +294,9 @@ void gr_blit(gr_surface source, int sx, int sy, int w, int h, int dx, int dy) {
     }
     GGLContext *gl = gr_context;
 
+    dx += overscan_offset_x;
+    dy += overscan_offset_y;
+
     gl->bindTexture(gl, (GGLSurface*) source);
     gl->texEnvi(gl, GGL_TEXTURE_ENV, GGL_TEXTURE_ENV_MODE, GGL_REPLACE);
     gl->texGeni(gl, GGL_S, GGL_TEXTURE_GEN_MODE, GGL_ONE_TO_ONE);
@@ -385,12 +406,12 @@ void gr_exit(void)
 
 int gr_fb_width(void)
 {
-    return gr_framebuffer[0].width;
+    return gr_framebuffer[0].width - 2*overscan_offset_x;
 }
 
 int gr_fb_height(void)
 {
-    return gr_framebuffer[0].height;
+    return gr_framebuffer[0].height - 2*overscan_offset_y;
 }
 
 gr_pixel *gr_fb_data(void)

minui/minui.h

@@ -36,7 +36,7 @@ void gr_flip(void);
 void gr_fb_blank(bool blank);
 
 void gr_color(unsigned char r, unsigned char g, unsigned char b, unsigned char a);
-void gr_fill(int x, int y, int w, int h);
+void gr_fill(int x1, int y1, int x2, int y2);
 int gr_text(int x, int y, const char *s);
  void gr_texticon(int x, int y, gr_surface icon);
 int gr_measure(const char *s);