it's working on web and in window, waow

src/render/render.c

@@ -0,0 +1,126 @@
+fn rn_cmd_t *rn_get_cmd(rn_cmd_kind_t kind) {
+    b32 alloc_new = false;
+    if (rn_state.last_cmd == NULL) {
+        alloc_new = true;
+    } else if (rn_state.last_cmd->kind != kind) {
+        alloc_new = true;
+    }
+
+    rn_cmd_t *result = rn_state.last_cmd;
+    if (alloc_new) {
+        result = ma_push_type(tcx.temp, rn_cmd_t);
+        result->kind = kind;
+        SLLQ_APPEND(rn_state.first_cmd, rn_state.last_cmd, result);
+
+        if (rn_cmd_kind_quad) {
+            result->vertex = rn_state.vertices + rn_state.len;
+        }
+    }
+
+    return result;
+}
+
+fn rn_vertex_t *rn_push_vertex(rn_cmd_t *cmd, u32 count) {
+    rn_vertex_t *result = cmd->vertex + cmd->len;
+    rn_state.len += count;
+    cmd->len += count;
+    return result;
+}
+
+fn void rn_push_quad(r2f32_t rect, r2f32_t tex, v4f32_t color) {
+    rn_cmd_t *cmd = rn_get_cmd(rn_cmd_kind_quad);
+    rn_vertex_t *v = rn_push_vertex(cmd, 6);
+    v[0] = (rn_vertex_t){
+        {rect.min.x, rect.max.y},
+        { tex.min.x,  tex.max.y},
+        color
+    };
+    v[1] = (rn_vertex_t){
+        {rect.max.x, rect.max.y},
+        { tex.max.x,  tex.max.y},
+        color
+    };
+    v[2] = (rn_vertex_t){
+        {rect.min.x, rect.min.y},
+        { tex.min.x,  tex.min.y},
+        color
+    };
+    v[3] = (rn_vertex_t){
+        {rect.min.x, rect.min.y},
+        { tex.min.x,  tex.min.y},
+        color
+    };
+    v[4] = (rn_vertex_t){
+        {rect.max.x, rect.max.y},
+        { tex.max.x,  tex.max.y},
+        color
+    };
+    v[5] = (rn_vertex_t){
+        {rect.max.x, rect.min.y},
+        { tex.max.x,  tex.min.y},
+        color
+    };
+}
+
+fn void rn_draw_rect(r2f32_t rect, v4f32_t color) {
+    rn_push_quad(rect, rn_state.main_font->white_texture_bounding_box, color);
+}
+
+fn void rn_draw_rect_border(r2f32_t rect, v4f32_t color, f32 border_thickness) {
+    r2f32_t left = r2f32_cut_left(&rect, border_thickness);
+    r2f32_t right = r2f32_cut_right(&rect, border_thickness);
+    r2f32_t top = r2f32_cut_top(&rect, border_thickness);
+    r2f32_t bottom = r2f32_cut_bottom(&rect, border_thickness);
+    rn_push_quad(left, rn_state.main_font->white_texture_bounding_box, color);
+    rn_push_quad(right, rn_state.main_font->white_texture_bounding_box, color);
+    rn_push_quad(top, rn_state.main_font->white_texture_bounding_box, color);
+    rn_push_quad(bottom, rn_state.main_font->white_texture_bounding_box, color);
+}
+
+fn i64 rn_get_char_spacing(rn_font_t *font, u32 codepoint) {
+    rn_glyph_t *g = rn_get_glyph(font, codepoint);
+    if (g->xadvance) return (i64)g->xadvance;
+    return (i64)g->size.x;
+}
+
+fn i64 rn_get_line_spacing(rn_font_t *font) {
+    i64 result = (i64)(font->ascent - font->descent + font->line_gap);
+    return result;
+}
+
+fn v2f32_t rn_base_draw_string(rn_font_t *font, s8_t string, v2f32_t pos, v4f32_t color, b32 draw) {
+    pos.y += rn_get_line_spacing(font) + font->descent;
+    v2f32_t original_pos = pos;
+
+    for (utf8_iter_t iter = utf8_iterate_ex(string.str, (int)string.len); iter.item; utf8_advance(&iter)) {
+        u32 codepoint = iter.item;
+        rn_glyph_t *g    = rn_get_glyph(font, codepoint);
+        r2f32_t rect = r2f32_mindim(v2f32_add(pos, g->offset), g->size);
+        if (draw && codepoint != '\n' && codepoint != ' ' && codepoint != '\t') {
+            rn_push_quad(rect, g->atlas_bounding_box, color);
+        }
+        pos.x += g->xadvance;
+    }
+
+
+    v2f32_t result = {pos.x - original_pos.x, font->size};
+    return result;
+}
+
+fn v2f32_t rn_draw_string(rn_font_t *font, v2f32_t pos, v4f32_t color, s8_t string) {
+    return rn_base_draw_string(font, string, pos, color, true);
+}
+
+fn v2f32_t rn_draw_stringf(rn_font_t *font, v2f32_t pos, v4f32_t color, char *str, ...) {
+    S8_FMT(tcx.temp, str, result);
+    return rn_draw_string(font, pos, color, result);
+}
+
+fn v2f32_t rn_measure_string(rn_font_t *font, s8_t string) {
+    return rn_base_draw_string(font, string, v2f32(0,0), v4f32(0,0,0,0), false);
+}
+
+fn void rn_set_clip(r2f32_t rect) {
+    rn_cmd_t *cmd = rn_get_cmd(rn_cmd_kind_set_clip);
+    cmd->rect = rect;
+}