1 files changed, 101 insertions, 16 deletions

diff --git a/src/graphics/texture.c b/src/graphics/texture.c
index f6549f1..2387fa7 100644
--- a/src/graphics/texture.c
+++ b/src/graphics/texture.c
@@ -3,7 +3,7 @@
 #include "../../include/mgl/mgl.h"
 #include <stdio.h>
 
-/* TODO: Check for glTexImage2D failure */
+/* TODO: Check for glTexImage2D/glTexSubImage2D failure */
 
 static int mgl_texture_format_to_opengl_format(mgl_texture_format format) {
     switch(format) {
@@ -49,11 +49,31 @@ static mgl_texture_format mgl_image_format_to_mgl_texture_format(mgl_image_forma
     return 0;
 }
 
-int mgl_texture_load_from_file(mgl_texture *self, const char *filepath, mgl_texture_load_options *load_options) {
+int mgl_texture_init(mgl_texture *self) {
     self->id = 0;
     self->width = 0;
     self->height = 0;
-    
+    self->format = 0;
+    self->max_width = 0;
+    self->max_height = 0;
+    self->pixel_coordinates = false;
+
+    mgl_context *context = mgl_get_context();
+    context->gl.glGenTextures(1, &self->id);
+    if(self->id == 0) {
+        fprintf(stderr, "Error: failed to init texture (glGenTextures failed)\n");
+        return -1;
+    }
+
+    int max_texture_size = 0;
+    context->gl.glGetIntegerv(GL_MAX_TEXTURE_SIZE, &max_texture_size);
+    self->max_width = max_texture_size;
+    self->max_height = max_texture_size;
+
+    return 0;
+}
+
+int mgl_texture_load_from_file(mgl_texture *self, const char *filepath, mgl_texture_load_options *load_options) {
     mgl_image image;
     if(mgl_image_load_from_file(&image, filepath) != 0)
         return -1;
@@ -68,21 +88,22 @@ int mgl_texture_load_from_image(mgl_texture *self, const mgl_image *image, mgl_t
 }
 
 int mgl_texture_load_from_memory(mgl_texture *self, const unsigned char *data, int width, int height, mgl_image_format format, mgl_texture_load_options *load_options) {
-    self->id = 0;
+    if(width < 0 || height < 0)
+        return -1;
+
+    if(width > self->max_width || height > self->max_height)
+        return -1;
+
     self->width = width;
     self->height = height;
     self->format = mgl_image_format_to_mgl_texture_format(format);
+    self->pixel_coordinates = load_options ? load_options->pixel_coordinates : false;
 
-    mgl_context *context = mgl_get_context();
-    context->gl.glGenTextures(1, &self->id);
-    if(self->id == 0) {
-        fprintf(stderr, "Error: failed to load image from memory (glGenTextures failed)\n");
-        mgl_texture_unload(self);
-        return -1;
-    }
-
-    const int opengl_texture_format = load_options && load_options->compressed ? mgl_texture_format_to_compressed_opengl_format(self->format) : mgl_texture_format_to_opengl_format(self->format);
+    int opengl_texture_format = mgl_texture_format_to_opengl_format(self->format);
+    if(load_options && load_options->compressed)
+        opengl_texture_format = mgl_texture_format_to_compressed_opengl_format(self->format);
 
+    mgl_context *context = mgl_get_context();
     context->gl.glBindTexture(GL_TEXTURE_2D, self->id);
     context->gl.glTexImage2D(GL_TEXTURE_2D, 0, opengl_texture_format, self->width, self->height, 0, mgl_texture_format_to_source_opengl_format(self->format), GL_UNSIGNED_BYTE, data);
     context->gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
@@ -94,13 +115,77 @@ int mgl_texture_load_from_memory(mgl_texture *self, const unsigned char *data, i
     return 0;
 }
 
+int mgl_texture_update(mgl_texture *self, const unsigned char *data, int offset_x, int offset_y, int width, int height, mgl_image_format format) {
+    if(offset_x + width > self->width || offset_y + height > self->height)
+        return -1;
+
+    mgl_context *context = mgl_get_context();
+    context->gl.glBindTexture(GL_TEXTURE_2D, self->id);
+    const mgl_texture_format texture_format = mgl_image_format_to_mgl_texture_format(format);
+    /* TODO: TODO: Only do one glTexSubImage2D */
+#if 1
+    for(int i = 0; i < height; ++i) {
+        context->gl.glTexSubImage2D(GL_TEXTURE_2D, 0, offset_x, offset_y + i, width, 1, mgl_texture_format_to_source_opengl_format(texture_format), GL_UNSIGNED_BYTE, data + (i * width));
+    }
+#else
+    context->gl.glTexSubImage2D(GL_TEXTURE_2D, 0, offset_x, offset_y, width, height, mgl_texture_format_to_source_opengl_format(texture_format), GL_UNSIGNED_BYTE, data);
+#endif
+    context->gl.glBindTexture(GL_TEXTURE_2D, 0);
+    return 0;
+}
+
+int mgl_texture_resize(mgl_texture *self, int new_width, int new_height, mgl_texture_load_options *load_options) {
+    if(new_width == self->width && new_height == self->height)
+        return 0;
+
+    if(new_width < 0 || new_height < 0)
+        return -1;
+
+    if(new_width > self->max_width || new_height > self->max_height)
+        return -1;
+
+    self->width = new_width;
+    self->height = new_height;
+
+    const int opengl_texture_format = load_options && load_options->compressed ? mgl_texture_format_to_compressed_opengl_format(self->format) : mgl_texture_format_to_opengl_format(self->format);
+
+    mgl_context *context = mgl_get_context();
+    context->gl.glBindTexture(GL_TEXTURE_2D, self->id);
+    context->gl.glTexImage2D(GL_TEXTURE_2D, 0, opengl_texture_format, self->width, self->height, 0, mgl_texture_format_to_source_opengl_format(self->format), GL_UNSIGNED_BYTE, NULL);
+    context->gl.glBindTexture(GL_TEXTURE_2D, 0);
+    return 0;
+}
+
+void mgl_texture_use(const mgl_texture *texture) {
+    mgl_context *context = mgl_get_context();
+
+    if(texture) {
+        float matrix[16] = {
+            1.0f, 0.0f, 0.0f, 0.0f,
+            0.0f, 1.0f, 0.0f, 0.0f,
+            0.0f, 0.0f, 1.0f, 0.0f,
+            0.0f, 0.0f, 0.0f, 1.0f,
+        };
+
+        if(texture->pixel_coordinates) {
+            matrix[0] = 1.0f / (float)texture->width;
+            matrix[5] = 1.0f / (float)texture->height;
+        }
+
+        context->gl.glMatrixMode(GL_TEXTURE);
+        context->gl.glLoadMatrixf(matrix);
+        context->gl.glMatrixMode(GL_MODELVIEW);
+
+        context->gl.glBindTexture(GL_TEXTURE_2D, texture->id);
+    } else {
+        context->gl.glBindTexture(GL_TEXTURE_2D, 0);
+    }
+}
+
 void mgl_texture_unload(mgl_texture *self) {
     mgl_context *context = mgl_get_context();
     if(self->id) {
         context->gl.glDeleteTextures(1, &self->id);
         self->id = 0;
     }
-    self->width = 0;
-    self->height = 0;
-    self->format = 0;
 }