1 files changed, 55 insertions, 0 deletions
diff --git a/texture.h b/texture.h
new file mode 100644
index 0000000..c51e411
--- /dev/null
+++ b/texture.h
@@ -0,0 +1,55 @@
+#define STB_IMAGE_IMPLEMENTATION
+#include "stb_image.h"
+
+texture_t load_texture(arena_t *arena, const char *filename, i32 gamma)
+{
+	texture_t texture = {0};
+	i32 nchannels;
+	stbi_set_flip_vertically_on_load(1);
+	u8 *data = stbi_load(filename, &texture.width, &texture.height, &nchannels, 0);
+	if (!data) {
+		printf("error: \"%s\" failed to load\n", filename);
+		return texture;
+	}
+
+	u32 internal_format, data_format;
+	switch (nchannels) {
+	case 1:
+		texture.type = texture_type_r;
+		internal_format = data_format = GL_RED;
+		break;
+	case 3:
+		texture.type = texture_type_rgb;
+		internal_format = gamma ? GL_SRGB : GL_RGB;
+		data_format = GL_RGB;
+		break;
+	case 4:
+		texture.type = texture_type_rgba;
+		internal_format = gamma ? GL_SRGB_ALPHA : GL_RGBA;
+		data_format = GL_RGBA;
+		break;
+	default:
+		printf("error: \"%s\" unsupported type\n", filename);
+		goto end;
+	}
+
+	u64 size = texture.type * texture.width * texture.height;
+	texture.data = push_arena(arena, size);
+	prb_memmove(texture.data, data, size);
+
+	glGenTextures(1, &texture.id);
+	glBindTexture(GL_TEXTURE_2D, texture.id);
+	glTexImage2D(GL_TEXTURE_2D, 0, internal_format, texture.width, texture.height,
+		0, data_format, GL_UNSIGNED_BYTE, texture.data);
+	glGenerateMipmap(GL_TEXTURE_2D);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+	glBindTexture(GL_TEXTURE_2D, 0);
+
+	printf("info: \"%s\" loaded successfully\n", filename);
+end:
+	stbi_image_free(data);
+	return texture;
+}