Add initial text system

1 files changed, 36 insertions, 33 deletions

diff --git a/src/main.c b/src/main.c
index 60faaea..7a8b6e7 100644
--- a/src/main.c
+++ b/src/main.c
@@ -7,7 +7,7 @@
 #include "shorthand.h"
 #include "bd-font.c"
 
-#define TEXT_OVERLAY_SIZE 10
+#define TEXT_OVERLAY_SIZE 5
 
 //
 // Callbacks.
@@ -225,31 +225,21 @@ init_debug_overlay(Context *ctx) {
     glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ctx->text_overlay.ebo);
     glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
 
-    // Texture atlas.
-    // TODO: Full 256 ascii font.
+    // Unpack texture atlas.
     u8 texture[256 * 8 * 8] = {0};
-    unpack_letter(&bd_font['A' * 2], (u32*)&texture[0]);
-    for (size_t i = 0; i < 8; ++i) {
-        printf("%02x %02x %02x %02x %02x %02x %02x %02x\n",
-                texture[0 + i * 8],
-                texture[1 + i * 8],
-                texture[2 + i * 8],
-                texture[3 + i * 8],
-                texture[4 + i * 8],
-                texture[5 + i * 8],
-                texture[6 + i * 8],
-                texture[7 + i * 8]);
+    for (size_t i = 0; i < 256; i++) {
+        unpack_letter(&bd_font[i * 2], (u32*)&texture[i * 8 * 8]);
     }
+
+    // Create texture for text.
     glGenTextures(1, &ctx->text_overlay.tex_id);
     glBindTexture(GL_TEXTURE_2D, ctx->text_overlay.tex_id);
     glTexImage2D(GL_TEXTURE_2D, 0,
             GL_R8,
-            8,  // Width
-            1 * 8,      // Height
+            8,            // Width
+            256 * 8,      // Height
             0, GL_RED,
             GL_UNSIGNED_BYTE, &texture);
-    // glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, sizeof(bd_font), 8, 0, GL_RED,
-    //         GL_UNSIGNED_BYTE, &bd_font);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
     glBindTexture(GL_TEXTURE_2D, 0);
@@ -272,7 +262,7 @@ init_debug_overlay(Context *ctx) {
 "uniform float size;\n"
 
 "void main() {\n"
-"    float N = 3;\n" // TODO: should be 256 for the full font.
+"    float N = 256;\n"
 "    float idx = offset.z;\n"
 "    float m = 1.0 / N;\n"
 "    float k = m * idx;\n"
@@ -289,8 +279,7 @@ init_debug_overlay(Context *ctx) {
 "    pos += scalar * offset.xy;\n"
 "    pos = mix(vec2(-1.0), vec2(1.0), pos);\n"
 "    gl_Position = vec4(pos, 0.0, 1.0);\n"
-// "    tex = tex_coords * vec2(1.0, m) + vec2(0.0, k);\n"
-"    tex = tex_coords;\n"
+"    tex = tex_coords * vec2(1.0, m) + vec2(0.0, k);\n"
 "}";
 
     // Fragment shader.
@@ -341,19 +330,33 @@ update_frame_time(Context *ctx) {
 }
 
 void
+clear_text(Context *ctx) {
+    ctx->text_overlay.cur_x = 0;
+    ctx->text_overlay.cur_y = 0;
+    ctx->text_overlay.n_chars = 0;
+}
+
+void
+add_text(Context *ctx, char *txt) {
+    while (*txt != '\0') {
+        if (*txt == '\n') {
+            ctx->text_overlay.cur_x = 0;
+            ctx->text_overlay.cur_y++;
+            txt++;
+            continue;
+        }
+        ctx->text_overlay.letters[ctx->text_overlay.n_chars].x = ctx->text_overlay.cur_x++;
+        ctx->text_overlay.letters[ctx->text_overlay.n_chars].y = ctx->text_overlay.cur_y;
+        ctx->text_overlay.letters[ctx->text_overlay.n_chars].idx = *txt++;
+        ctx->text_overlay.n_chars++;
+    }
+}
+
+void
 update_text(Context *ctx) {
-    // TODO: Test with the full font atlas and characters.
-    // TODO: add_text function for setting up letters[] based on a char* + n_chars.
-    ctx->text_overlay.letters[0].x = 0;
-    ctx->text_overlay.letters[0].y = 0;
-    ctx->text_overlay.letters[0].idx = 0;
-    ctx->text_overlay.letters[1].x = 1;
-    ctx->text_overlay.letters[1].y = 0;
-    ctx->text_overlay.letters[1].idx = 1;
-    ctx->text_overlay.letters[2].x = 2;
-    ctx->text_overlay.letters[2].y = 0;
-    ctx->text_overlay.letters[2].idx = 2;
-    ctx->text_overlay.n_chars = 3;
+    clear_text(ctx);
+    add_text(ctx, "hello world!");
+
     glBindBuffer(GL_ARRAY_BUFFER, ctx->text_overlay.vbo);
     glBufferData(GL_ARRAY_BUFFER,
             sizeof(struct Letter) * ctx->text_overlay.n_chars,