Add backbuffer

src/display/texture/texture.c

@@ -0,0 +1,91 @@
+/**
+ * Copyright (c) 2025 Dominic Masters
+ * 
+ * This software is released under the MIT License.
+ * https://opensource.org/licenses/MIT
+ */
+
+#include "texture.h"
+#include "assert/assert.h"
+#include "util/memory.h"
+#include "util/math.h"
+
+const texture_t *TEXTURE_BOUND = NULL;
+
+void textureInit(
+  texture_t *texture,
+  const int32_t width,
+  const int32_t height,
+  const textureformat_t format,
+  const void *data
+) {
+  assertNotNull(texture, "Texture cannot be NULL");
+  assertTrue(width > 0 && height > 0, "width/height must be greater than 0");
+
+  memoryZero(texture, sizeof(texture_t));
+  texture->width = width;
+  texture->height = height;
+
+  #if PSP
+    assertTrue(
+      width == mathNextPowTwo(width),
+      "Width must be powers of 2 for PSP"
+    );
+    assertTrue(
+      height == mathNextPowTwo(height),
+      "Height must be powers of 2 for PSP"
+    );
+  #endif
+
+  #if DUSK_DISPLAY_SDL2
+    glGenTextures(1, &texture->id);
+    glBindTexture(GL_TEXTURE_2D, texture->id);
+    glTexImage2D(
+      GL_TEXTURE_2D, 0, format, width, height, 0,
+      format, GL_UNSIGNED_BYTE, data
+    );
+
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    
+    glBindTexture(GL_TEXTURE_2D, 0);
+  #endif
+}
+
+void textureBind(const texture_t *texture) {
+  if(TEXTURE_BOUND == texture) return;
+
+  if(texture == NULL) {
+    #if DUSK_DISPLAY_SDL2
+      glDisable(GL_TEXTURE_2D);
+    #endif
+    TEXTURE_BOUND = NULL;
+    return;
+  }
+
+  assertTrue(
+    texture->id != 0,
+    "Texture ID must not be 0"
+  );
+  assertTrue(
+    texture->width > 0 && texture->height > 0,
+    "Texture width and height must be greater than 0"
+  );
+
+  #if DUSK_DISPLAY_SDL2
+    glEnable(GL_TEXTURE_2D);
+    glBindTexture(GL_TEXTURE_2D, texture->id);
+  #endif
+  TEXTURE_BOUND = texture;
+}
+
+void textureDispose(texture_t *texture) {
+  assertNotNull(texture, "Texture cannot be NULL");
+  assertTrue(texture->id != 0, "Texture ID must not be 0");
+
+  #if DUSK_DISPLAY_SDL2
+    glDeleteTextures(1, &texture->id);
+  #endif
+}