Another demo change to fix High DPI screens

demo/glfw_opengl2/nuklear_glfw_gl2.h

@@ -143,7 +143,7 @@ nk_glfw3_render(enum nk_anti_aliasing AA, int max_vertex_buffer, int max_element
             glBindTexture(GL_TEXTURE_2D, (GLuint)cmd->texture.id);
             glScissor(
                 (GLint)(cmd->clip_rect.x * glfw.fb_scale.x),
-                (GLint)((glfw.display_height - (GLint)(cmd->clip_rect.y + cmd->clip_rect.h)) * glfw.fb_scale.y),
+                (GLint)((glfw.height - (GLint)(cmd->clip_rect.y + cmd->clip_rect.h)) * glfw.fb_scale.y),
                 (GLint)(cmd->clip_rect.w * glfw.fb_scale.x),
                 (GLint)(cmd->clip_rect.h * glfw.fb_scale.y));
             glDrawElements(GL_TRIANGLES, (GLsizei)cmd->elem_count, GL_UNSIGNED_SHORT, offset);

demo/glfw_opengl3/nuklear_glfw_gl3.h

@@ -263,7 +263,7 @@ nk_glfw3_render(enum nk_anti_aliasing AA, int max_vertex_buffer, int max_element
             glBindTexture(GL_TEXTURE_2D, (GLuint)cmd->texture.id);
             glScissor(
                 (GLint)(cmd->clip_rect.x * glfw.fb_scale.x),
-                (GLint)((glfw.display_height - (GLint)(cmd->clip_rect.y + cmd->clip_rect.h)) * glfw.fb_scale.y),
+                (GLint)((glfw.height - (GLint)(cmd->clip_rect.y + cmd->clip_rect.h)) * glfw.fb_scale.y),
                 (GLint)(cmd->clip_rect.w * glfw.fb_scale.x),
                 (GLint)(cmd->clip_rect.h * glfw.fb_scale.y));
             glDrawElements(GL_TRIANGLES, (GLsizei)cmd->elem_count, GL_UNSIGNED_SHORT, offset);

demo/sdl_opengl2/nuklear_sdl_gl2.h

@@ -132,7 +132,7 @@ nk_sdl_render(enum nk_anti_aliasing AA, int max_vertex_buffer, int max_element_b
             glBindTexture(GL_TEXTURE_2D, (GLuint)cmd->texture.id);
             glScissor(
                 (GLint)(cmd->clip_rect.x * scale.x),
-                (GLint)((display_height - (GLint)(cmd->clip_rect.y + cmd->clip_rect.h)) * scale.y),
+                (GLint)((height - (GLint)(cmd->clip_rect.y + cmd->clip_rect.h)) * scale.y),
                 (GLint)(cmd->clip_rect.w * scale.x),
                 (GLint)(cmd->clip_rect.h * scale.y));
             glDrawElements(GL_TRIANGLES, (GLsizei)cmd->elem_count, GL_UNSIGNED_SHORT, offset);

demo/sdl_opengl3/nuklear_sdl_gl3.h

@@ -254,7 +254,7 @@ nk_sdl_render(enum nk_anti_aliasing AA, int max_vertex_buffer, int max_element_b
             glBindTexture(GL_TEXTURE_2D, (GLuint)cmd->texture.id);
             glScissor(
                 (GLint)(cmd->clip_rect.x * scale.x),
-                (GLint)((display_height - (GLint)(cmd->clip_rect.y + cmd->clip_rect.h)) * scale.y),
+                (GLint)((height - (GLint)(cmd->clip_rect.y + cmd->clip_rect.h)) * scale.y),
                 (GLint)(cmd->clip_rect.w * scale.x),
                 (GLint)(cmd->clip_rect.h * scale.y));