WIP: Implement text rendering

lib/zgl

@@ -1 +1 @@
-Subproject commit 9fc2524bbf2e1172a5cb218eca37dc99930a31db
+Subproject commit cac42e0692374742036f14d44379dd085c084caa

src/MainMenu.zig

@@ -80,10 +80,10 @@ pub fn getSelIdx(self: Self, offset: i32) usize {
         }
         //ret = len - @mod(-offset - sel, len - 1);
         //ret = @mod(0, 2);
-        std.debug.print("len {},offset {},ret {}, sel {}\n", .{ len, offset, ret, sel });
+        //std.debug.print("len {},offset {},ret {}, sel {}\n", .{ len, offset, ret, sel });
     } else {
         ret = @mod(offset + sel, len);
-        std.debug.print("len {},offset {},ret {}, sel {}\n", .{ len, offset, ret, sel });
+        //std.debug.print("len {},offset {},ret {}, sel {}\n", .{ len, offset, ret, sel });
     }
 
     return @intCast(usize, ret);

src/Renderer.zig

@@ -15,7 +15,7 @@ color: [4]f32,
 test_counter: usize = 0,
 
 vbo: [max_objects]f32 = .{0.0} ** max_objects,
-colors: [max_objects][4]f32 = .{[4]f32{ 0.0, 0.0, 0.0, 1.0 }} ** max_objects,
+//colors: [max_objects][4]f32 = .{[4]f32{ 0.0, 0.0, 0.0, 1.0 }} ** max_objects,
 vbo_index: usize = 0,
 
 const max_objects: usize = 16384;
@@ -27,6 +27,7 @@ fn glGetProcAddress(p: []const u8, proc: [:0]const u8) ?*const anyopaque {
 
 pub fn init() !Self {
     try sdl.init(.{ .video = true, .audio = true, .events = true });
+    try sdl.ttf.init();
 
     try sdl.gl.setAttribute(.{ .context_major_version = 3 });
     try sdl.gl.setAttribute(.{ .context_minor_version = 3 });
@@ -52,7 +53,6 @@ pub fn init() !Self {
 
     // Shader stuff
     var mvp_loc: u32 = undefined;
-    //var color_loc: u32 = undefined;
     const program = gl.Program.create();
     {
         const vs = gl.Shader.create(.vertex);
@@ -74,7 +74,6 @@ pub fn init() !Self {
         program.link();
 
         mvp_loc = program.uniformLocation("mvp").?;
-        //color_loc = program.uniformLocation("color").?;
     }
     program.use();
 
@@ -95,18 +94,24 @@ pub fn init() !Self {
     const buf = gl.Buffer.gen();
     buf.bind(.array_buffer);
 
-    gl.vertexAttribPointer(0, 2, .float, false, @sizeOf(f32) * 6, @sizeOf(f32) * 0);
+    gl.vertexAttribPointer(0, 2, .float, false, @sizeOf(f32) * 8, @sizeOf(f32) * 0);
     gl.enableVertexAttribArray(0);
 
-    gl.vertexAttribPointer(1, 4, .float, false, @sizeOf(f32) * 6, @sizeOf(f32) * 2);
+    gl.vertexAttribPointer(1, 4, .float, false, @sizeOf(f32) * 8, @sizeOf(f32) * 2);
     gl.enableVertexAttribArray(1);
 
+    gl.vertexAttribPointer(2, 2, .float, false, @sizeOf(f32) * 8, @sizeOf(f32) * 6);
+    gl.enableVertexAttribArray(2);
+
     gl.clearColor(0.91, 0.85, 0.65, 1.00);
 
     // TODO: See if there's a more optimal solution to this, maybe activating only when necessary
     gl.enable(.blend);
     gl.blendFunc(.src_alpha, .one_minus_src_alpha);
 
+    var text = Text.init("testing123");
+    text.deinit();
+
     return Self{ .window = window, .context = ctx, .buffer = buf, .color = .{ 0, 0, 0, 0 } };
 }
 
@@ -130,6 +135,7 @@ pub fn render(self: *Self) void {
 pub fn deinit(self: *Self) void {
     gl.disableVertexAttribArray(0);
     sdl.quit();
+    sdl.ttf.quit();
     self.window.destroy();
     sdl.gl.deleteContext(self.context);
 }
@@ -158,7 +164,6 @@ pub fn drawRectangle(self: *Self, x: i32, y: i32, w: i32, h: i32) void {
 }
 
 pub fn fillRectangle(self: *Self, x: i32, y: i32, w: i32, h: i32) void {
-    //const indices = [_]u8{ 1, 3, 0, 1, 3, 2 };
     self.fillRectangleEx(x, y, w, h, 0);
 }
 
@@ -166,8 +171,6 @@ pub fn fillRectangleEx(self: *Self, x: i32, y: i32, w: i32, h: i32, skew_x: i32)
     // TODO: Is this still necessary?
     self.test_counter += 1;
 
-    //gl.uniform4fv(self.color_loc, &.{self.color});
-
     var xf = @intToFloat(f32, x);
     var yf = @intToFloat(f32, y);
     var wf = @intToFloat(f32, w);
@@ -176,28 +179,28 @@ pub fn fillRectangleEx(self: *Self, x: i32, y: i32, w: i32, h: i32, skew_x: i32)
     const skew_x_offset = @intToFloat(f32, skew_x) * hf / 100;
 
     const i = self.vbo_index;
-    const vertex_data = [36]f32{
+    const vertex_data = [_]f32{
         xf + skew_x_offset, yf, // up-left
-        self.color[0],      self.color[1],
-        self.color[2],      self.color[3],
+        self.color[0], self.color[1], self.color[2], self.color[3],
+        0.0, 0.0,
         xf + wf + skew_x_offset, yf, // up-right
-        self.color[0],           self.color[1],
-        self.color[2],           self.color[3],
+        self.color[0], self.color[1], self.color[2], self.color[3],
+        1.0, 0.0,
         xf - skew_x_offset, yf + hf, // down-left
-        self.color[0],      self.color[1],
-        self.color[2],      self.color[3],
+        self.color[0], self.color[1], self.color[2], self.color[3],
+        0.0, 1.0,
         xf + wf - skew_x_offset, yf + hf, // down-right
-        self.color[0],           self.color[1],
-        self.color[2],           self.color[3],
+        self.color[0], self.color[1], self.color[2], self.color[3],
+        1.0, 1.0,
         xf + wf + skew_x_offset, yf, // up-right
-        self.color[0],           self.color[1],
-        self.color[2],           self.color[3],
+        self.color[0], self.color[1], self.color[2], self.color[3],
+        1.0, 0.0,
         xf - skew_x_offset, yf + hf, // down-left
-        self.color[0],      self.color[1],
-        self.color[2],      self.color[3],
+        self.color[0], self.color[1], self.color[2], self.color[3],
+        0.0, 1.0,
     };
-    std.mem.copy(f32, self.vbo[i .. i + 36], &vertex_data);
-    self.vbo_index += 36;
+    std.mem.copy(f32, self.vbo[i .. i + vertex_data.len], &vertex_data);
+    self.vbo_index += vertex_data.len;
 }
 
 fn renderRectangle(self: *Self, x: i32, y: i32, w: i32, h: i32) void {
@@ -212,3 +215,60 @@ pub fn getOutputSize(self: Self) OutputSize {
         .height = wsize.height,
     };
 }
+
+const image = [_]u8{
+    // 1
+    0,0,0,
+    255,255,255,
+    0,0,0,
+    255,255,255,
+    // 2
+    255,255,255,
+    0,0,0,
+    255,255,255,
+    0,0,0,
+    // 1
+    0,0,0,
+    255,255,255,
+    0,0,0,
+    255,255,255,
+    // 2
+    255,255,255,
+    0,0,0,
+    255,255,255,
+    0,0,0,
+};
+
+const Text = struct {
+    texture: gl.Texture,
+
+    pub fn init(text: [:0]const u8) Text {
+        var tex = gl.genTexture();
+        //defer gl.Texture.delete(tex);
+        gl.bindTexture(tex, .@"2d");
+
+        var font = sdl.ttf.openFont("res/fonts/MarginaliaRegular-8XlZ.ttf", 200) catch unreachable;
+        //defer font.close();
+        var surface = font.renderTextBlended(text, sdl.Color.white) catch unreachable;
+        const width = @intCast(usize, surface.ptr.w);
+        const height = @intCast(usize, surface.ptr.h);
+        var newsurf = sdl.c.SDL_ConvertSurfaceFormat(surface.ptr, @enumToInt(sdl.PixelFormatEnum.argb8888), 0) orelse unreachable;
+        const data = @ptrCast([*]const u8, newsurf.pixels);
+        //defer surface.destroy();
+
+        gl.textureImage2D(.@"2d", 0, .rgba, width, height, .rgba, .unsigned_byte, data);
+
+        gl.texParameter(.@"2d", .wrap_s, .clamp_to_edge);
+        gl.texParameter(.@"2d", .wrap_r, .clamp_to_edge);
+        gl.texParameter(.@"2d", .min_filter, .linear);
+        gl.texParameter(.@"2d", .mag_filter, .linear);
+
+        return Text {
+            .texture = tex,
+        };
+    }
+
+    pub fn deinit(self: *Text) void {
+        _ = self;
+    }
+};

src/shaders/fragment.fs

@@ -1,7 +1,9 @@
 #version 330 core
 
 in vec4 color;
+in vec2 Texcoord;
+uniform sampler2D tex;
 
 void main(){
-     gl_FragColor = color;
+     gl_FragColor = texture(tex, Texcoord) * color;
 }

src/shaders/vector.vs

@@ -2,12 +2,15 @@
 
 layout (location = 0) in vec2 pos;
 layout (location = 1) in vec4 v_color;
+layout (location = 2) in vec2 texcoord;
+out vec2 Texcoord;
 
 uniform mat4 mvp;
 
 out vec4 color;
 
 void main() {
+     Texcoord = texcoord;
      color = v_color;
      gl_Position = mvp * vec4((pos + vec2(0.5, 0.5)), 0, 1);
 }