aboutsummaryrefslogtreecommitdiff
path: root/nuklear/demo/glfw_opengl2/nuklear_glfw_gl2.h
blob: 93af773fbd2f307acabcd658792c03d109d82611 (plain)
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
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
/*
 * Nuklear - v1.17 - public domain
 * no warrenty implied; use at your own risk.
 * authored from 2015-2016 by Micha Mettke
 */
/*
 * ==============================================================
 *
 *                              API
 *
 * ===============================================================
 */
#ifndef NK_GLFW_GL2_H_
#define NK_GLFW_GL2_H_

#include <GLFW/glfw3.h>

enum nk_glfw_init_state{
    NK_GLFW3_DEFAULT = 0,
    NK_GLFW3_INSTALL_CALLBACKS
};
NK_API struct nk_context*   nk_glfw3_init(GLFWwindow *win, enum nk_glfw_init_state);
NK_API void                 nk_glfw3_font_stash_begin(struct nk_font_atlas **atlas);
NK_API void                 nk_glfw3_font_stash_end(void);

NK_API void                 nk_glfw3_new_frame(void);
NK_API void                 nk_glfw3_render(enum nk_anti_aliasing , int max_vertex_buffer, int max_element_buffer);
NK_API void                 nk_glfw3_shutdown(void);

NK_API void                 nk_glfw3_char_callback(GLFWwindow *win, unsigned int codepoint);
NK_API void                 nk_gflw3_scroll_callback(GLFWwindow *win, double xoff, double yoff);

#endif

/*
 * ==============================================================
 *
 *                          IMPLEMENTATION
 *
 * ===============================================================
 */
#ifdef NK_GLFW_GL2_IMPLEMENTATION

#ifndef NK_GLFW_TEXT_MAX
#define NK_GLFW_TEXT_MAX 256
#endif

struct nk_glfw_device {
    struct nk_buffer cmds;
    struct nk_draw_null_texture null;
    GLuint font_tex;
};

struct nk_glfw_vertex {
    float position[2];
    float uv[2];
    nk_byte col[4];
};

static struct nk_glfw {
    GLFWwindow *win;
    int width, height;
    int display_width, display_height;
    struct nk_glfw_device ogl;
    struct nk_context ctx;
    struct nk_font_atlas atlas;
    struct nk_vec2 fb_scale;
    unsigned int text[NK_GLFW_TEXT_MAX];
    int text_len;
    float scroll;
} glfw;

NK_INTERN void
nk_glfw3_device_upload_atlas(const void *image, int width, int height)
{
    struct nk_glfw_device *dev = &glfw.ogl;
    glGenTextures(1, &dev->font_tex);
    glBindTexture(GL_TEXTURE_2D, dev->font_tex);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, (GLsizei)width, (GLsizei)height, 0,
                GL_RGBA, GL_UNSIGNED_BYTE, image);
}

NK_API void
nk_glfw3_render(enum nk_anti_aliasing AA, int max_vertex_buffer, int max_element_buffer)
{
    /* setup global state */
    struct nk_glfw_device *dev = &glfw.ogl;
    glPushAttrib(GL_ENABLE_BIT|GL_COLOR_BUFFER_BIT|GL_TRANSFORM_BIT);
    glDisable(GL_CULL_FACE);
    glDisable(GL_DEPTH_TEST);
    glEnable(GL_SCISSOR_TEST);
    glEnable(GL_BLEND);
    glEnable(GL_TEXTURE_2D);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

    /* setup viewport/project */
    glViewport(0,0,(GLsizei)glfw.display_width,(GLsizei)glfw.display_height);
    glMatrixMode(GL_PROJECTION);
    glPushMatrix();
    glLoadIdentity();
    glOrtho(0.0f, glfw.width, glfw.height, 0.0f, -1.0f, 1.0f);
    glMatrixMode(GL_MODELVIEW);
    glPushMatrix();
    glLoadIdentity();

    glEnableClientState(GL_VERTEX_ARRAY);
    glEnableClientState(GL_TEXTURE_COORD_ARRAY);
    glEnableClientState(GL_COLOR_ARRAY);
    {
        GLsizei vs = sizeof(struct nk_glfw_vertex);
        size_t vp = offsetof(struct nk_glfw_vertex, position);
        size_t vt = offsetof(struct nk_glfw_vertex, uv);
        size_t vc = offsetof(struct nk_glfw_vertex, col);

        /* convert from command queue into draw list and draw to screen */
        const struct nk_draw_command *cmd;
        const nk_draw_index *offset = NULL;
        struct nk_buffer vbuf, ebuf;

        /* fill convert configuration */
        struct nk_convert_config config;
        static const struct nk_draw_vertex_layout_element vertex_layout[] = {
            {NK_VERTEX_POSITION, NK_FORMAT_FLOAT, NK_OFFSETOF(struct nk_glfw_vertex, position)},
            {NK_VERTEX_TEXCOORD, NK_FORMAT_FLOAT, NK_OFFSETOF(struct nk_glfw_vertex, uv)},
            {NK_VERTEX_COLOR, NK_FORMAT_R8G8B8A8, NK_OFFSETOF(struct nk_glfw_vertex, col)},
            {NK_VERTEX_LAYOUT_END}
        };
        NK_MEMSET(&config, 0, sizeof(config));
        config.vertex_layout = vertex_layout;
        config.vertex_size = sizeof(struct nk_glfw_vertex);
        config.vertex_alignment = NK_ALIGNOF(struct nk_glfw_vertex);
        config.null = dev->null;
        config.circle_segment_count = 22;
        config.curve_segment_count = 22;
        config.arc_segment_count = 22;
        config.global_alpha = 1.0f;
        config.shape_AA = AA;
        config.line_AA = AA;

        /* convert shapes into vertexes */
        nk_buffer_init_default(&vbuf);
        nk_buffer_init_default(&ebuf);
        nk_convert(&glfw.ctx, &dev->cmds, &vbuf, &ebuf, &config);

        /* setup vertex buffer pointer */
        {const void *vertices = nk_buffer_memory_const(&vbuf);
        glVertexPointer(2, GL_FLOAT, vs, (const void*)((const nk_byte*)vertices + vp));
        glTexCoordPointer(2, GL_FLOAT, vs, (const void*)((const nk_byte*)vertices + vt));
        glColorPointer(4, GL_UNSIGNED_BYTE, vs, (const void*)((const nk_byte*)vertices + vc));}

        /* iterate over and execute each draw command */
        offset = (const nk_draw_index*)nk_buffer_memory_const(&ebuf);
        nk_draw_foreach(cmd, &glfw.ctx, &dev->cmds)
        {
            if (!cmd->elem_count) continue;
            glBindTexture(GL_TEXTURE_2D, (GLuint)cmd->texture.id);
            glScissor(
                (GLint)(cmd->clip_rect.x * glfw.fb_scale.x),
                (GLint)((glfw.height - (GLint)(cmd->clip_rect.y + cmd->clip_rect.h)) * glfw.fb_scale.y),
                (GLint)(cmd->clip_rect.w * glfw.fb_scale.x),
                (GLint)(cmd->clip_rect.h * glfw.fb_scale.y));
            glDrawElements(GL_TRIANGLES, (GLsizei)cmd->elem_count, GL_UNSIGNED_SHORT, offset);
            offset += cmd->elem_count;
        }
        nk_clear(&glfw.ctx);
        nk_buffer_free(&vbuf);
        nk_buffer_free(&ebuf);
    }

    /* default OpenGL state */
    glDisableClientState(GL_VERTEX_ARRAY);
    glDisableClientState(GL_TEXTURE_COORD_ARRAY);
    glDisableClientState(GL_COLOR_ARRAY);

    glDisable(GL_CULL_FACE);
    glDisable(GL_DEPTH_TEST);
    glDisable(GL_SCISSOR_TEST);
    glDisable(GL_BLEND);
    glDisable(GL_TEXTURE_2D);

    glBindTexture(GL_TEXTURE_2D, 0);
    glMatrixMode(GL_MODELVIEW);
    glPopMatrix();
    glMatrixMode(GL_PROJECTION);
    glPopMatrix();
    glPopAttrib();
}

NK_API void
nk_glfw3_char_callback(GLFWwindow *win, unsigned int codepoint)
{
    (void)win;
    if (glfw.text_len < NK_GLFW_TEXT_MAX)
        glfw.text[glfw.text_len++] = codepoint;
}

NK_API void
nk_gflw3_scroll_callback(GLFWwindow *win, double xoff, double yoff)
{
    (void)win; (void)xoff;
    glfw.scroll += (float)yoff;
}

NK_INTERN void
nk_glfw3_clipbard_paste(nk_handle usr, struct nk_text_edit *edit)
{
    const char *text = glfwGetClipboardString(glfw.win);
    if (text) nk_textedit_paste(edit, text, nk_strlen(text));
    (void)usr;
}

NK_INTERN void
nk_glfw3_clipbard_copy(nk_handle usr, const char *text, int len)
{
    char *str = 0;
    (void)usr;
    if (!len) return;
    str = (char*)malloc((size_t)len+1);
    if (!str) return;
    memcpy(str, text, (size_t)len);
    str[len] = '\0';
    glfwSetClipboardString(glfw.win, str);
    free(str);
}

NK_API struct nk_context*
nk_glfw3_init(GLFWwindow *win, enum nk_glfw_init_state init_state)
{
    glfw.win = win;
    if (init_state == NK_GLFW3_INSTALL_CALLBACKS) {
        glfwSetScrollCallback(win, nk_gflw3_scroll_callback);
        glfwSetCharCallback(win, nk_glfw3_char_callback);
    }

    nk_init_default(&glfw.ctx, 0);
    glfw.ctx.clip.copy = nk_glfw3_clipbard_copy;
    glfw.ctx.clip.paste = nk_glfw3_clipbard_paste;
    glfw.ctx.clip.userdata = nk_handle_ptr(0);
    nk_buffer_init_default(&glfw.ogl.cmds);
    return &glfw.ctx;
}

NK_API void
nk_glfw3_font_stash_begin(struct nk_font_atlas **atlas)
{
    nk_font_atlas_init_default(&glfw.atlas);
    nk_font_atlas_begin(&glfw.atlas);
    *atlas = &glfw.atlas;
}

NK_API void
nk_glfw3_font_stash_end(void)
{
    const void *image; int w, h;
    image = nk_font_atlas_bake(&glfw.atlas, &w, &h, NK_FONT_ATLAS_RGBA32);
    nk_glfw3_device_upload_atlas(image, w, h);
    nk_font_atlas_end(&glfw.atlas, nk_handle_id((int)glfw.ogl.font_tex), &glfw.ogl.null);
    if (glfw.atlas.default_font)
        nk_style_set_font(&glfw.ctx, &glfw.atlas.default_font->handle);
}

NK_API void
nk_glfw3_new_frame(void)
{
    int i;
    double x, y;
    struct nk_context *ctx = &glfw.ctx;
    struct GLFWwindow *win = glfw.win;

    glfwGetWindowSize(win, &glfw.width, &glfw.height);
    glfwGetFramebufferSize(win, &glfw.display_width, &glfw.display_height);
    glfw.fb_scale.x = (float)glfw.display_width/(float)glfw.width;
    glfw.fb_scale.y = (float)glfw.display_height/(float)glfw.height;

    nk_input_begin(ctx);
    for (i = 0; i < glfw.text_len; ++i)
        nk_input_unicode(ctx, glfw.text[i]);

    /* optional grabbing behavior */
    if (ctx->input.mouse.grab)
        glfwSetInputMode(glfw.win, GLFW_CURSOR, GLFW_CURSOR_HIDDEN);
    else if (ctx->input.mouse.ungrab)
        glfwSetInputMode(glfw.win, GLFW_CURSOR, GLFW_CURSOR_NORMAL);

    nk_input_key(ctx, NK_KEY_DEL, glfwGetKey(win, GLFW_KEY_DELETE) == GLFW_PRESS);
    nk_input_key(ctx, NK_KEY_ENTER, glfwGetKey(win, GLFW_KEY_ENTER) == GLFW_PRESS);
    nk_input_key(ctx, NK_KEY_TAB, glfwGetKey(win, GLFW_KEY_TAB) == GLFW_PRESS);
    nk_input_key(ctx, NK_KEY_BACKSPACE, glfwGetKey(win, GLFW_KEY_BACKSPACE) == GLFW_PRESS);
    nk_input_key(ctx, NK_KEY_UP, glfwGetKey(win, GLFW_KEY_UP) == GLFW_PRESS);
    nk_input_key(ctx, NK_KEY_DOWN, glfwGetKey(win, GLFW_KEY_DOWN) == GLFW_PRESS);
    nk_input_key(ctx, NK_KEY_TEXT_START, glfwGetKey(win, GLFW_KEY_HOME) == GLFW_PRESS);
    nk_input_key(ctx, NK_KEY_TEXT_END, glfwGetKey(win, GLFW_KEY_END) == GLFW_PRESS);
    nk_input_key(ctx, NK_KEY_SCROLL_START, glfwGetKey(win, GLFW_KEY_HOME) == GLFW_PRESS);
    nk_input_key(ctx, NK_KEY_SCROLL_END, glfwGetKey(win, GLFW_KEY_END) == GLFW_PRESS);
    nk_input_key(ctx, NK_KEY_SCROLL_DOWN, glfwGetKey(win, GLFW_KEY_PAGE_DOWN) == GLFW_PRESS);
    nk_input_key(ctx, NK_KEY_SCROLL_UP, glfwGetKey(win, GLFW_KEY_PAGE_UP) == GLFW_PRESS);
    nk_input_key(ctx, NK_KEY_SHIFT, glfwGetKey(win, GLFW_KEY_LEFT_SHIFT) == GLFW_PRESS||
                                    glfwGetKey(win, GLFW_KEY_RIGHT_SHIFT) == GLFW_PRESS);

    if (glfwGetKey(win, GLFW_KEY_LEFT_CONTROL) == GLFW_PRESS ||
        glfwGetKey(win, GLFW_KEY_RIGHT_CONTROL) == GLFW_PRESS) {
        nk_input_key(ctx, NK_KEY_COPY, glfwGetKey(win, GLFW_KEY_C) == GLFW_PRESS);
        nk_input_key(ctx, NK_KEY_PASTE, glfwGetKey(win, GLFW_KEY_P) == GLFW_PRESS);
        nk_input_key(ctx, NK_KEY_CUT, glfwGetKey(win, GLFW_KEY_X) == GLFW_PRESS);
        nk_input_key(ctx, NK_KEY_TEXT_UNDO, glfwGetKey(win, GLFW_KEY_Z) == GLFW_PRESS);
        nk_input_key(ctx, NK_KEY_TEXT_REDO, glfwGetKey(win, GLFW_KEY_R) == GLFW_PRESS);
        nk_input_key(ctx, NK_KEY_TEXT_WORD_LEFT, glfwGetKey(win, GLFW_KEY_LEFT) == GLFW_PRESS);
        nk_input_key(ctx, NK_KEY_TEXT_WORD_RIGHT, glfwGetKey(win, GLFW_KEY_RIGHT) == GLFW_PRESS);
        nk_input_key(ctx, NK_KEY_TEXT_LINE_START, glfwGetKey(win, GLFW_KEY_B) == GLFW_PRESS);
        nk_input_key(ctx, NK_KEY_TEXT_LINE_END, glfwGetKey(win, GLFW_KEY_E) == GLFW_PRESS);
    } else {
        nk_input_key(ctx, NK_KEY_LEFT, glfwGetKey(win, GLFW_KEY_LEFT) == GLFW_PRESS);
        nk_input_key(ctx, NK_KEY_RIGHT, glfwGetKey(win, GLFW_KEY_RIGHT) == GLFW_PRESS);
        nk_input_key(ctx, NK_KEY_COPY, 0);
        nk_input_key(ctx, NK_KEY_PASTE, 0);
        nk_input_key(ctx, NK_KEY_CUT, 0);
        nk_input_key(ctx, NK_KEY_SHIFT, 0);
    }

    glfwGetCursorPos(win, &x, &y);
    nk_input_motion(ctx, (int)x, (int)y);
    if (ctx->input.mouse.grabbed) {
        glfwSetCursorPos(glfw.win, ctx->input.mouse.prev.x, ctx->input.mouse.prev.y);
        ctx->input.mouse.pos.x = ctx->input.mouse.prev.x;
        ctx->input.mouse.pos.y = ctx->input.mouse.prev.y;
    }

    nk_input_button(ctx, NK_BUTTON_LEFT, (int)x, (int)y, glfwGetMouseButton(win, GLFW_MOUSE_BUTTON_LEFT) == GLFW_PRESS);
    nk_input_button(ctx, NK_BUTTON_MIDDLE, (int)x, (int)y, glfwGetMouseButton(win, GLFW_MOUSE_BUTTON_MIDDLE) == GLFW_PRESS);
    nk_input_button(ctx, NK_BUTTON_RIGHT, (int)x, (int)y, glfwGetMouseButton(win, GLFW_MOUSE_BUTTON_RIGHT) == GLFW_PRESS);
    nk_input_scroll(ctx, glfw.scroll);
    nk_input_end(&glfw.ctx);
    glfw.text_len = 0;
    glfw.scroll = 0;
}

NK_API
void nk_glfw3_shutdown(void)
{
    struct nk_glfw_device *dev = &glfw.ogl;
    nk_font_atlas_clear(&glfw.atlas);
    nk_free(&glfw.ctx);
    glDeleteTextures(1, &dev->font_tex);
    nk_buffer_free(&dev->cmds);
    memset(&glfw, 0, sizeof(glfw));
}

#endif