-
Notifications
You must be signed in to change notification settings - Fork 0
/
glfontstash.zig
180 lines (150 loc) · 7.36 KB
/
glfontstash.zig
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
const std = @import("std");
const fons = @import("fontstash.zig");
const gl = @import("example/deps/zgl/zgl.zig");
pub const GlState = struct {
texture: gl.Texture = gl.Texture.invalid,
vertexArray: gl.VertexArray = gl.VertexArray.invalid,
vertexBuffer: gl.Buffer = gl.Buffer.invalid,
tcoordBuffer: gl.Buffer = gl.Buffer.invalid,
colorBuffer: gl.Buffer = gl.Buffer.invalid,
width: usize = 0,
height: usize = 0,
};
pub const ZeroPosition = enum(c_int) {
TopLeft = 1,
BottomLeft = 2,
};
pub fn create( state: *GlState, width: u32, height: u32, zero: ZeroPosition ) !fons.Context {
var params = fons.Params {
.width = @intCast(c_int, width),
.height = @intCast(c_int, height),
.flags = @intCast(u8, @enumToInt(zero)),
.renderCreate = fonsRenderCreate,
.renderResize = fonsRenderResize,
.renderUpdate = fonsRenderUpdate,
.renderDraw = fonsRenderDraw,
.renderDelete = fonsRenderDelete,
.userPtr = state,
};
return try fons.createInternal(¶ms);
}
pub fn delete( context: *fons.Context ) void {
fons.deleteInternal( &context.context );
}
pub fn color2int( r: u8, g: u8, b: u8, a: u8 ) u32 {
return (@intCast(u32, r)) | (@intCast(u32, g) << 8) | (@intCast(u32, b) << 16) | (@intCast(u32, a) << 24);
}
fn fonsRenderCreate( userPtr: ?*anyopaque, width: c_int, height: c_int) callconv(.C) c_int {
const state = @ptrCast(*GlState, @alignCast(@alignOf(*GlState), userPtr.?));
if (state.texture != gl.Texture.invalid) {
gl.deleteTexture(state.texture);
state.texture = gl.Texture.invalid;
}
state.texture = gl.genTexture();
if (state.texture == gl.Texture.invalid) {
return 0;
}
if (state.vertexArray == gl.VertexArray.invalid) {
state.vertexArray = gl.genVertexArray();
}
if (state.vertexArray == gl.VertexArray.invalid) {
return 0;
}
if (state.vertexBuffer == gl.Buffer.invalid) {
state.vertexBuffer = gl.genBuffer();
}
if (state.vertexBuffer == gl.Buffer.invalid) {
return 0;
}
if (state.tcoordBuffer == gl.Buffer.invalid) {
state.tcoordBuffer = gl.genBuffer();
}
if (state.tcoordBuffer == gl.Buffer.invalid) {
return 0;
}
if (state.colorBuffer == gl.Buffer.invalid) {
state.colorBuffer = gl.genBuffer();
}
if (state.colorBuffer == gl.Buffer.invalid) {
return 0;
}
state.width = @intCast(usize, width);
state.height = @intCast(usize, height);
state.texture.bind(gl.TextureTarget.@"2d");
gl.textureImage2D(gl.TextureTarget.@"2d", 0, gl.PixelFormat.red, state.width, state.height, gl.PixelFormat.red, gl.PixelType.unsigned_byte, null);
gl.texParameter( gl.TextureTarget.@"2d", gl.TextureParameter.min_filter, gl.TextureParameterType(gl.TextureParameter.min_filter).linear);
gl.texParameter( gl.TextureTarget.@"2d", gl.TextureParameter.mag_filter, gl.TextureParameterType(gl.TextureParameter.mag_filter).linear);
gl.texParameter( gl.TextureTarget.@"2d", gl.TextureParameter.swizzle_r, gl.TextureParameterType(gl.TextureParameter.swizzle_r).one);
gl.texParameter( gl.TextureTarget.@"2d", gl.TextureParameter.swizzle_g, gl.TextureParameterType(gl.TextureParameter.swizzle_g).one);
gl.texParameter( gl.TextureTarget.@"2d", gl.TextureParameter.swizzle_b, gl.TextureParameterType(gl.TextureParameter.swizzle_b).one);
gl.texParameter( gl.TextureTarget.@"2d", gl.TextureParameter.swizzle_a, gl.TextureParameterType(gl.TextureParameter.swizzle_a).red);
return 1;
}
fn fonsRenderResize( userPtr: ?*anyopaque, width: c_int, height: c_int) callconv(.C) c_int {
return fonsRenderCreate(userPtr, width, height);
}
fn fonsRenderUpdate( userPtr: ?*anyopaque, rect: [*c]c_int, data: [*c]const u8) callconv(.C) void {
const state = @ptrCast(*GlState, @alignCast(@alignOf(*GlState), userPtr.?));
var w = rect[2] - rect[0];
var h = rect[3] - rect[1];
if (state.texture == gl.Texture.invalid) {
return;
}
var alignment = gl.getInteger(gl.Parameter.unpack_alignment);
var rowLength = gl.getInteger(gl.Parameter.unpack_row_length);
var skipPixels = gl.getInteger(gl.Parameter.unpack_skip_pixels);
var skipRows = gl.getInteger(gl.Parameter.unpack_skip_rows);
state.texture.bind(gl.TextureTarget.@"2d");
gl.pixelStore(gl.PixelStoreParameter.unpack_alignment, 1);
gl.pixelStore(gl.PixelStoreParameter.unpack_row_length, @intCast(usize, state.width));
gl.pixelStore(gl.PixelStoreParameter.unpack_skip_pixels, @intCast(usize, rect[0]));
gl.pixelStore(gl.PixelStoreParameter.unpack_skip_rows, @intCast(usize, rect[1]));
gl.texSubImage2D( gl.TextureTarget.@"2d", 0, @intCast(usize, rect[0]), @intCast(usize, rect[1]), @intCast(usize, w), @intCast(usize, h), gl.PixelFormat.red, gl.PixelType.unsigned_byte, data);
gl.pixelStore(gl.PixelStoreParameter.unpack_alignment, @intCast(usize, alignment));
gl.pixelStore(gl.PixelStoreParameter.unpack_row_length, @intCast(usize, rowLength));
gl.pixelStore(gl.PixelStoreParameter.unpack_skip_pixels, @intCast(usize, skipPixels));
gl.pixelStore(gl.PixelStoreParameter.unpack_skip_rows, @intCast(usize, skipRows));
}
fn fonsRenderDraw( userPtr: ?*anyopaque, verts: [*c]const f32, tcoords: [*c]const f32, colors: [*c]const c_uint, nverts: c_int) callconv(.C) void {
const state = @ptrCast(*GlState, @alignCast(@alignOf(*GlState), userPtr.?));
if (state.texture == gl.Texture.invalid or state.vertexArray == gl.VertexArray.invalid) {
return;
}
gl.activeTexture(gl.TextureUnit.texture_0);
state.texture.bind(gl.TextureTarget.@"2d");
state.vertexArray.bind();
const fonsVertexAttrib = 0;
gl.enableVertexAttribArray(fonsVertexAttrib);
state.vertexBuffer.bind(gl.BufferTarget.array_buffer);
const VertFormat = packed struct {
x: f32,
y: f32,
};
gl.bufferData(gl.BufferTarget.array_buffer, VertFormat, @ptrCast([*]const VertFormat, verts)[0..@intCast(usize, nverts)], gl.BufferUsage.dynamic_draw);
gl.vertexAttribPointer(fonsVertexAttrib, 2, gl.Type.float, false, 0, 0);
const fonsTCoordAttrib = 1;
gl.enableVertexAttribArray(fonsTCoordAttrib);
state.tcoordBuffer.bind(gl.BufferTarget.array_buffer);
const TCoordFormat = packed struct {
u: f32,
v: f32,
};
gl.bufferData(gl.BufferTarget.array_buffer, TCoordFormat, @ptrCast([*]const TCoordFormat, tcoords)[0..@intCast(usize, nverts)], gl.BufferUsage.dynamic_draw);
gl.vertexAttribPointer(fonsTCoordAttrib, 2, gl.Type.float, false, 0, 0);
const fonsColorAttrib = 2;
gl.enableVertexAttribArray(fonsColorAttrib);
state.colorBuffer.bind(gl.BufferTarget.array_buffer);
gl.bufferData(gl.BufferTarget.array_buffer, u32, @ptrCast([*]const u32, colors)[0..@intCast(usize, nverts)], gl.BufferUsage.dynamic_draw);
gl.vertexAttribPointer(fonsColorAttrib, 4, gl.Type.unsigned_byte, true, 0, 0);
gl.drawArrays(gl.PrimitiveType.triangles, 0, @intCast(usize, nverts));
gl.disableVertexAttribArray(fonsVertexAttrib);
gl.disableVertexAttribArray(fonsTCoordAttrib);
gl.disableVertexAttribArray(fonsColorAttrib);
gl.bindVertexArray(gl.VertexArray.invalid);
}
fn fonsRenderDelete( userPtr: ?*anyopaque ) callconv(.C) void {
const state = @ptrCast(*GlState, @alignCast(@alignOf(*GlState), userPtr.?));
if (state.texture != gl.Texture.invalid) {
state.texture.delete();
}
}