diff -r 77493525eac2 -r d8d2e4817db1 src/texture.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/texture.c	Tue Apr 09 21:18:52 2024 +0200
@@ -0,0 +1,87 @@
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+ * Copyright 2024 Mike Becker. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   1. Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer.
+ *
+ *   2. Redistributions in binary form must reproduce the above copyright
+ *      notice, this list of conditions and the following disclaimer in the
+ *      documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "ascension/texture.h"
+#include "ascension/error.h"
+
+#include <assert.h>
+#include <GL/glew.h>
+
+void asc_texture_bind(AscTexture const *tex, int uniform_location, int unit) {
+    glActiveTexture(GL_TEXTURE0 + unit);
+    GLenum error = glGetError();
+    if (error == GL_INVALID_ENUM) {
+        asc_error("Tried to use more texture units than available.");
+    }
+    glBindTexture(tex->target, tex->tex_id);
+    glUniform1i(uniform_location, unit);
+}
+
+void asc_texture_from_surface(AscTexture *tex, SDL_Surface const *surface) {
+    glBindTexture(tex->target,tex->tex_id);
+    glPixelStorei(GL_UNPACK_ROW_LENGTH,
+                  surface->pitch / surface->format->BytesPerPixel);
+    glTexImage2D(tex->target, 0, GL_RGBA,
+                 surface->w, surface->h,
+                 0, GL_BGRA,
+                 GL_UNSIGNED_BYTE, surface->pixels);
+}
+
+void asc_texture_init(
+        AscTexture *tex,
+        enum asc_texture_target target,
+        enum asc_texture_min_filter min_filter,
+        enum asc_texture_mag_filter mag_filter
+) {
+    static const GLenum texture_targets[] = {
+            GL_TEXTURE_RECTANGLE
+    };
+    static const GLint texture_filters[] = {
+            GL_NEAREST,
+            GL_LINEAR,
+            GL_NEAREST_MIPMAP_NEAREST,
+            GL_LINEAR_MIPMAP_NEAREST,
+            GL_NEAREST_MIPMAP_LINEAR,
+            GL_LINEAR_MIPMAP_LINEAR
+    };
+    assert(target < sizeof(texture_targets) / sizeof(GLenum));
+    assert(min_filter < sizeof(texture_filters) / sizeof(GLint));
+    assert(mag_filter < 2); // mag filter only supports nearest/linear
+    tex->target = texture_targets[target];
+    glGenTextures(1, &tex->tex_id);
+    glBindTexture(tex->target, tex->tex_id);
+    glTexParameteri(tex->target, GL_TEXTURE_MIN_FILTER,
+                    texture_filters[min_filter]);
+    glTexParameteri(tex->target, GL_TEXTURE_MAG_FILTER,
+                    texture_filters[mag_filter]);
+    asc_dprintf("Generated new texture for text node: %u", tex->tex_id);
+}
+
+void asc_texture_destroy(AscTexture *tex) {
+    asc_dprintf("Release text node texture: %u", tex->tex_id);
+    glDeleteTextures(1, &tex->tex_id);
+}