win32 gui: replace D2D renderer with D3d11 shader

src/win32/dwrite.zig

@@ -0,0 +1,96 @@
+const std = @import("std");
+const win32 = @import("win32").everything;
+
+const FontFace = @import("FontFace.zig");
+const XY = @import("xy.zig").XY;
+
+const global = struct {
+    var init_called: bool = false;
+    var dwrite_factory: *win32.IDWriteFactory = undefined;
+};
+
+pub fn init() void {
+    std.debug.assert(!global.init_called);
+    global.init_called = true;
+    {
+        const hr = win32.DWriteCreateFactory(
+            win32.DWRITE_FACTORY_TYPE_SHARED,
+            win32.IID_IDWriteFactory,
+            @ptrCast(&global.dwrite_factory),
+        );
+        if (hr < 0) fatalHr("DWriteCreateFactory", hr);
+    }
+}
+
+pub const Font = struct {
+    text_format: *win32.IDWriteTextFormat,
+    cell_size: XY(u16),
+
+    pub fn init(dpi: u32, size: f32, face: *const FontFace) Font {
+        var text_format: *win32.IDWriteTextFormat = undefined;
+        {
+            const hr = global.dwrite_factory.CreateTextFormat(
+                face.ptr(),
+                null,
+                .NORMAL, //weight
+                .NORMAL, // style
+                .NORMAL, // stretch
+                win32.scaleDpi(f32, size, dpi),
+                win32.L(""), // locale
+                &text_format,
+            );
+            if (hr < 0) std.debug.panic(
+                "CreateTextFormat '{}' height {d} failed, hresult=0x{x}",
+                .{ std.unicode.fmtUtf16le(face.slice()), size, @as(u32, @bitCast(hr)) },
+            );
+        }
+        errdefer _ = text_format.IUnknown.Release();
+
+        const cell_size = blk: {
+            var text_layout: *win32.IDWriteTextLayout = undefined;
+            {
+                const hr = global.dwrite_factory.CreateTextLayout(
+                    win32.L("█"),
+                    1,
+                    text_format,
+                    std.math.floatMax(f32),
+                    std.math.floatMax(f32),
+                    &text_layout,
+                );
+                if (hr < 0) fatalHr("CreateTextLayout", hr);
+            }
+            defer _ = text_layout.IUnknown.Release();
+
+            var metrics: win32.DWRITE_TEXT_METRICS = undefined;
+            {
+                const hr = text_layout.GetMetrics(&metrics);
+                if (hr < 0) fatalHr("GetMetrics", hr);
+            }
+            break :blk .{
+                .x = @as(u16, @intFromFloat(@floor(metrics.width))),
+                .y = @as(u16, @intFromFloat(@floor(metrics.height))),
+            };
+        };
+
+        return .{
+            .text_format = text_format,
+            .cell_size = cell_size,
+        };
+    }
+
+    pub fn deinit(self: *Font) void {
+        _ = self.text_format.IUnknown.Release();
+        self.* = undefined;
+    }
+
+    pub fn getCellSize(self: Font, comptime T: type) XY(T) {
+        return .{
+            .x = @intCast(self.cell_size.x),
+            .y = @intCast(self.cell_size.y),
+        };
+    }
+};
+
+fn fatalHr(what: []const u8, hresult: win32.HRESULT) noreturn {
+    std.debug.panic("{s} failed, hresult=0x{x}", .{ what, @as(u32, @bitCast(hresult)) });
+}