Support use of custom fonts in miniui

Bug: 29547343
Change-Id: I398160c85daac90ffab2fa9bb2e96795b9e9885a
(cherry picked from commit 35fff61b1c0d736d090a1cd1bb4e99141cc88ad8)
diff --git a/minui/font_10x18.h b/minui/font_10x18.h
index 29d7053..30dfb9c 100644
--- a/minui/font_10x18.h
+++ b/minui/font_10x18.h
@@ -1,14 +1,14 @@
 struct {
   unsigned width;
   unsigned height;
-  unsigned cwidth;
-  unsigned cheight;
+  unsigned char_width;
+  unsigned char_height;
   unsigned char rundata[2973];
 } font = {
   .width = 960,
   .height = 18,
-  .cwidth = 10,
-  .cheight = 18,
+  .char_width = 10,
+  .char_height = 18,
   .rundata = {
 0x7f,0x7f,0x7f,0x7f,0x7f,0x7f,0x7f,0x55,0x82,0x06,0x82,0x02,0x82,0x10,0x82,
 0x11,0x83,0x08,0x82,0x0a,0x82,0x04,0x82,0x46,0x82,0x08,0x82,0x07,0x84,0x06,
diff --git a/minui/graphics.cpp b/minui/graphics.cpp
index c0eea9e..43ec83f 100644
--- a/minui/graphics.cpp
+++ b/minui/graphics.cpp
@@ -35,12 +35,6 @@
 #include "minui.h"
 #include "graphics.h"
 
-struct GRFont {
-    GRSurface* texture;
-    int cwidth;
-    int cheight;
-};
-
 static GRFont* gr_font = NULL;
 static minui_backend* gr_backend = NULL;
 
@@ -60,15 +54,20 @@
     return x < 0 || x >= gr_draw->width || y < 0 || y >= gr_draw->height;
 }
 
-int gr_measure(const char *s)
+const GRFont* gr_sys_font()
 {
-    return gr_font->cwidth * strlen(s);
+    return gr_font;
 }
 
-void gr_font_size(int *x, int *y)
+int gr_measure(const GRFont* font, const char *s)
 {
-    *x = gr_font->cwidth;
-    *y = gr_font->cheight;
+    return font->char_width * strlen(s);
+}
+
+void gr_font_size(const GRFont* font, int *x, int *y)
+{
+    *x = font->char_width;
+    *y = font->char_height;
 }
 
 static void text_blend(unsigned char* src_p, int src_row_bytes,
@@ -103,34 +102,32 @@
     }
 }
 
-void gr_text(int x, int y, const char *s, bool bold)
+void gr_text(const GRFont* font, int x, int y, const char *s, bool bold)
 {
-    GRFont* font = gr_font;
-
     if (!font->texture || gr_current_a == 0) return;
 
-    bold = bold && (font->texture->height != font->cheight);
+    bold = bold && (font->texture->height != font->char_height);
 
     x += overscan_offset_x;
     y += overscan_offset_y;
 
     unsigned char ch;
     while ((ch = *s++)) {
-        if (outside(x, y) || outside(x+font->cwidth-1, y+font->cheight-1)) break;
+        if (outside(x, y) || outside(x+font->char_width-1, y+font->char_height-1)) break;
 
         if (ch < ' ' || ch > '~') {
             ch = '?';
         }
 
-        unsigned char* src_p = font->texture->data + ((ch - ' ') * font->cwidth) +
-                               (bold ? font->cheight * font->texture->row_bytes : 0);
+        unsigned char* src_p = font->texture->data + ((ch - ' ') * font->char_width) +
+                               (bold ? font->char_height * font->texture->row_bytes : 0);
         unsigned char* dst_p = gr_draw->data + y*gr_draw->row_bytes + x*gr_draw->pixel_bytes;
 
         text_blend(src_p, font->texture->row_bytes,
                    dst_p, gr_draw->row_bytes,
-                   font->cwidth, font->cheight);
+                   font->char_width, font->char_height);
 
-        x += font->cwidth;
+        x += font->char_width;
     }
 }
 
@@ -267,40 +264,51 @@
     return surface->height;
 }
 
+int gr_init_font(const char* name, GRFont* dest) {
+    int res = res_create_alpha_surface(name, &(dest->texture));
+    if (res < 0) {
+        return res;
+    }
+
+    // The font image should be a 96x2 array of character images.  The
+    // columns are the printable ASCII characters 0x20 - 0x7f.  The
+    // top row is regular text; the bottom row is bold.
+    dest->char_width = dest->texture->width / 96;
+    dest->char_height = dest->texture->height / 2;
+
+    return 0;
+}
+
 static void gr_init_font(void)
 {
     gr_font = reinterpret_cast<GRFont*>(calloc(sizeof(*gr_font), 1));
 
-    int res = res_create_alpha_surface("font", &(gr_font->texture));
+    int res = gr_init_font("font", gr_font);
     if (res == 0) {
-        // The font image should be a 96x2 array of character images.  The
-        // columns are the printable ASCII characters 0x20 - 0x7f.  The
-        // top row is regular text; the bottom row is bold.
-        gr_font->cwidth = gr_font->texture->width / 96;
-        gr_font->cheight = gr_font->texture->height / 2;
-    } else {
-        printf("failed to read font: res=%d\n", res);
-
-        // fall back to the compiled-in font.
-        gr_font->texture = reinterpret_cast<GRSurface*>(malloc(sizeof(*gr_font->texture)));
-        gr_font->texture->width = font.width;
-        gr_font->texture->height = font.height;
-        gr_font->texture->row_bytes = font.width;
-        gr_font->texture->pixel_bytes = 1;
-
-        unsigned char* bits = reinterpret_cast<unsigned char*>(malloc(font.width * font.height));
-        gr_font->texture->data = reinterpret_cast<unsigned char*>(bits);
-
-        unsigned char data;
-        unsigned char* in = font.rundata;
-        while((data = *in++)) {
-            memset(bits, (data & 0x80) ? 255 : 0, data & 0x7f);
-            bits += (data & 0x7f);
-        }
-
-        gr_font->cwidth = font.cwidth;
-        gr_font->cheight = font.cheight;
+        return;
     }
+
+    printf("failed to read font: res=%d\n", res);
+
+    // fall back to the compiled-in font.
+    gr_font->texture = reinterpret_cast<GRSurface*>(malloc(sizeof(*gr_font->texture)));
+    gr_font->texture->width = font.width;
+    gr_font->texture->height = font.height;
+    gr_font->texture->row_bytes = font.width;
+    gr_font->texture->pixel_bytes = 1;
+
+    unsigned char* bits = reinterpret_cast<unsigned char*>(malloc(font.width * font.height));
+    gr_font->texture->data = reinterpret_cast<unsigned char*>(bits);
+
+    unsigned char data;
+    unsigned char* in = font.rundata;
+    while((data = *in++)) {
+        memset(bits, (data & 0x80) ? 255 : 0, data & 0x7f);
+        bits += (data & 0x7f);
+    }
+
+    gr_font->char_width = font.char_width;
+    gr_font->char_height = font.char_height;
 }
 
 #if 0
diff --git a/minui/minui.h b/minui/minui.h
index 5362d3f..f6b42c6 100644
--- a/minui/minui.h
+++ b/minui/minui.h
@@ -33,6 +33,12 @@
     unsigned char* data;
 };
 
+struct GRFont {
+    GRSurface* texture;
+    int char_width;
+    int char_height;
+};
+
 int gr_init();
 void gr_exit();
 
@@ -45,10 +51,14 @@
 void gr_clear();  // clear entire surface to current color
 void gr_color(unsigned char r, unsigned char g, unsigned char b, unsigned char a);
 void gr_fill(int x1, int y1, int x2, int y2);
-void gr_text(int x, int y, const char *s, bool bold);
+
 void gr_texticon(int x, int y, GRSurface* icon);
-int gr_measure(const char *s);
-void gr_font_size(int *x, int *y);
+
+const GRFont* gr_sys_font();
+int gr_init_font(const char* name, GRFont* dest);
+void gr_text(const GRFont* font, int x, int y, const char *s, bool bold);
+int gr_measure(const GRFont* font, const char *s);
+void gr_font_size(const GRFont* font, int *x, int *y);
 
 void gr_blit(GRSurface* source, int sx, int sy, int w, int h, int dx, int dy);
 unsigned int gr_get_width(GRSurface* surface);
diff --git a/screen_ui.cpp b/screen_ui.cpp
index c617272..fab3489 100644
--- a/screen_ui.cpp
+++ b/screen_ui.cpp
@@ -248,7 +248,7 @@
 }
 
 void ScreenRecoveryUI::DrawTextLine(int x, int* y, const char* line, bool bold) {
-    gr_text(x, *y, line, bold);
+    gr_text(gr_sys_font(), x, *y, line, bold);
     *y += char_height_ + 4;
 }
 
@@ -304,10 +304,10 @@
                     gr_fill(0, y - 2, gr_fb_width(), y + char_height_ + 2);
                     // Bold white text for the selected item.
                     SetColor(MENU_SEL_FG);
-                    gr_text(4, y, menu_[i], true);
+                    gr_text(gr_sys_font(), 4, y, menu_[i], true);
                     SetColor(MENU);
                 } else {
-                    gr_text(4, y, menu_[i], false);
+                    gr_text(gr_sys_font(), 4, y, menu_[i], false);
                 }
                 y += char_height_ + 4;
             }
@@ -323,7 +323,7 @@
         for (int ty = gr_fb_height() - char_height_;
              ty >= y && count < text_rows_;
              ty -= char_height_, ++count) {
-            gr_text(0, ty, text_[row], false);
+            gr_text(gr_sys_font(), 0, ty, text_[row], false);
             --row;
             if (row < 0) row = text_rows_ - 1;
         }
@@ -442,7 +442,7 @@
     density_ = static_cast<float>(android::base::GetIntProperty("ro.sf.lcd_density", 160)) / 160.f;
     is_large_ = gr_fb_height() > PixelsFromDp(800);
 
-    gr_font_size(&char_width_, &char_height_);
+    gr_font_size(gr_sys_font(), &char_width_, &char_height_);
     text_rows_ = gr_fb_height() / char_height_;
     text_cols_ = gr_fb_width() / char_width_;
 
diff --git a/wear_ui.cpp b/wear_ui.cpp
index 1788907..5433d11 100644
--- a/wear_ui.cpp
+++ b/wear_ui.cpp
@@ -177,7 +177,7 @@
             // items don't fit on the screen.
             if (menu_items > menu_end - menu_start) {
                 sprintf(cur_selection_str, "Current item: %d/%d", menu_sel + 1, menu_items);
-                gr_text(x+4, y, cur_selection_str, 1);
+                gr_text(gr_sys_font(), x+4, y, cur_selection_str, 1);
                 y += char_height_+4;
             }
 
@@ -192,10 +192,10 @@
                     gr_fill(x, y-2, gr_fb_width()-x, y+char_height_+2);
                     // white text of selected item
                     SetColor(MENU_SEL_FG);
-                    if (menu[i][0]) gr_text(x+4, y, menu[i], 1);
+                    if (menu[i][0]) gr_text(gr_sys_font(), x+4, y, menu[i], 1);
                     SetColor(MENU);
-                } else {
-                    if (menu[i][0]) gr_text(x+4, y, menu[i], 0);
+                } else if (menu[i][0]) {
+                    gr_text(gr_sys_font(), x+4, y, menu[i], 0);
                 }
                 y += char_height_+4;
             }
@@ -216,7 +216,7 @@
         for (int ty = gr_fb_height() - char_height_ - outer_height;
              ty > y+2 && count < text_rows;
              ty -= char_height_, ++count) {
-            gr_text(x+4, ty, text[row], 0);
+            gr_text(gr_sys_font(), x+4, ty, text[row], 0);
             --row;
             if (row < 0) row = text_rows-1;
         }
@@ -285,7 +285,7 @@
 {
     gr_init();
 
-    gr_font_size(&char_width_, &char_height_);
+    gr_font_size(gr_sys_font(), &char_width_, &char_height_);
 
     text_col = text_row = 0;
     text_rows = (gr_fb_height()) / char_height_;