Rename imv_texture -> imv_image

1 files changed, 132 insertions, 0 deletions

diff --git a/src/image.c b/src/image.c
new file mode 100644
index 0000000..5c9d9b5
--- /dev/null
+++ b/src/image.c
@@ -0,0 +1,132 @@
+#include "image.h"
+
+struct imv_image *imv_image_create(SDL_Renderer *r)
+{
+  struct imv_image *image = malloc(sizeof(struct imv_image));
+  memset(image, 0, sizeof(struct imv_image));
+  image->renderer = r;
+
+  SDL_RendererInfo ri;
+  SDL_GetRendererInfo(r, &ri);
+  image->chunk_width = ri.max_texture_width != 0 ? ri.max_texture_width : 4096;
+  image->chunk_height = ri.max_texture_height != 0 ? ri.max_texture_height : 4096;
+  return image;
+}
+
+void imv_image_free(struct imv_image *image)
+{
+  if(image->num_chunks > 0) {
+    for(int i = 0; i < image->num_chunks; ++i) {
+      SDL_DestroyTexture(image->chunks[i]);
+    }
+    free(image->chunks);
+    image->num_chunks = 0;
+    image->chunks = NULL;
+    image->renderer = NULL;
+  }
+  free(image);
+}
+
+int imv_image_set_bitmap(struct imv_image *image, FIBITMAP *bmp)
+{
+  image->width = FreeImage_GetWidth(bmp);
+  image->height = FreeImage_GetHeight(bmp);
+
+  /* figure out how many chunks are needed, and create them */
+  if(image->num_chunks > 0) {
+    for(int i = 0; i < image->num_chunks; ++i) {
+      SDL_DestroyTexture(image->chunks[i]);
+    }
+    free(image->chunks);
+  }
+
+  image->num_chunks_wide = 1 + image->width / image->chunk_width;
+  image->num_chunks_tall = 1 + image->height / image->chunk_height;
+
+  image->last_chunk_width = image->width % image->chunk_width;
+  image->last_chunk_height = image->height % image->chunk_height;
+
+  if(image->last_chunk_width == 0) {
+    image->last_chunk_width = image->chunk_width;
+  }
+  if(image->last_chunk_height == 0) {
+    image->last_chunk_height = image->chunk_height;
+  }
+
+  image->num_chunks = image->num_chunks_wide * image->num_chunks_tall;
+  image->chunks = malloc(sizeof(SDL_Texture*) * image->num_chunks);
+
+  int failed_at = -1;
+  for(int y = 0; y < image->num_chunks_tall; ++y) {
+    for(int x = 0; x < image->num_chunks_wide; ++x) {
+      const int is_last_h_chunk = (x == image->num_chunks_wide - 1);
+      const int is_last_v_chunk = (y == image->num_chunks_tall - 1);
+      image->chunks[x + y * image->num_chunks_wide] =
+        SDL_CreateTexture(image->renderer,
+          SDL_PIXELFORMAT_ARGB8888,
+          SDL_TEXTUREACCESS_STATIC,
+          is_last_h_chunk ? image->last_chunk_width : image->chunk_width,
+          is_last_v_chunk ? image->last_chunk_height : image->chunk_height);
+      SDL_SetTextureBlendMode(image->chunks[x + y * image->num_chunks_wide],
+          SDL_BLENDMODE_BLEND);
+      if(image->chunks[x + y * image->num_chunks_wide] == NULL) {
+        failed_at = x + y * image->num_chunks_wide;
+        break;
+      }
+    }
+  }
+
+  if(failed_at != -1) {
+    for(int i = 0; i <= failed_at; ++i) {
+      SDL_DestroyTexture(image->chunks[i]);
+    }
+    free(image->chunks);
+    image->num_chunks = 0;
+    image->chunks = NULL;
+    return 1;
+  }
+
+  BYTE* pixels = malloc(4 * image->width * image->height);
+  FreeImage_ConvertToRawBits(pixels, bmp, 4 * image->width, 32,
+      FI_RGBA_RED_MASK, FI_RGBA_GREEN_MASK, FI_RGBA_BLUE_MASK, TRUE);
+
+  for(int y = 0; y < image->num_chunks_tall; ++y) {
+    for(int x = 0; x < image->num_chunks_wide; ++x) {
+      ptrdiff_t offset = 4 * x * image->chunk_width +
+        y * 4 * image->width * image->chunk_height;
+      BYTE* addr = pixels + offset;
+      SDL_UpdateTexture(image->chunks[x + y * image->num_chunks_wide],
+          NULL, addr, 4 * image->width);
+    }
+  }
+
+  free(pixels);
+  return 0;
+}
+
+void imv_image_draw(struct imv_image *image, int bx, int by, double scale)
+{
+  int offset_x = 0;
+  int offset_y = 0;
+  for(int y = 0; y < image->num_chunks_tall; ++y) {
+    for(int x = 0; x < image->num_chunks_wide; ++x) {
+      int img_w, img_h;
+      SDL_QueryTexture(image->chunks[x + y * image->num_chunks_wide], NULL, NULL,
+        &img_w, &img_h);
+      SDL_Rect view_area = {
+        bx + offset_x,
+        by + offset_y,
+        img_w * scale,
+        img_h * scale
+      };
+      SDL_RenderCopy(image->renderer,
+          image->chunks[x + y * image->num_chunks_wide], NULL, &view_area);
+      offset_x += image->chunk_width * scale;
+    }
+    offset_x = 0;
+    offset_y += image->chunk_height * scale;
+  }
+}
+
+
+/* vim:set ts=2 sts=2 sw=2 et: */